VintageBigBlue.org

 

Re: PemPro shows the 76 sec error. 1st steps at fixing:


Aug 23, 2007

 


----------------------------

#33815 Aug 23, 2007

Greetings,

Well, after 5 cycles of PemPro2 last night, my G11 shows the 76

sec error. Overall PE was pretty good, without any PEC.



Today, I pulled the RA worm, and inspected the blocks. The block

farthest from the motor was actually convex on the underside, with

the curvature running the same direction as the worm shaft.



No problem, I thought, I'll just knock off the high spots and flatten

it right out! Unfortunately, the high spot is directly over the

thinnest portion of the bearing block. That portion is almost paper

thin as it is. I couldn't take off nearly enough metal to flatten

the bottom of the block.



I then decided to try shimming the outsides of the block with binder

paper (similar to a website I saw recently, where the owner shimmed

one side of the block.)



My hope is that this will relieve some of the pressure on the bearing

race. I also noticed that the bearing block closest to the motor was

not the right height. I cannot remember at the moment if it was a

little too high or too low.



It seems to me that the quality of the bearing block assembly is much

lower than that of the rest of the mount. Aside from the difficulty

in getting the worm adjusted properly, which is a nuisance, the

blocks themselves seem to be relatively poorly machined, and poorly

aligned.



I'll keep you posted on the PemPro results from tonight.



Regards,



Gary



----------------------------

#33816 Aug 23, 2007

"No problem, I thought, I'll just knock off the high spots and flatten

it right out! Unfortunately, the high spot is directly over the

thinnest portion of the bearing block. That portion is almost paper

thin as it is. I couldn't take off nearly enough metal to flatten

the bottom of the block."



This IS exactly the high spot that is causing the error. With the bearing in place, file the high spot off. It doesn't matter how this the area becomes......even if the bearing is exposed. As long as the bearing isn't a new high spot. If it is, you need a replacement block.





---Frank Rocketman Uroda



----- Original Message -----

From: gary_teamgs

To: Losmandy_users@yahoogroups.com

Sent: Thursday, August 23, 2007 7:57 PM

Subject: [Losmandy_users] PemPro shows the 76 sec error. 1st steps at fixing:





Greetings,

Well, after 5 cycles of PemPro2 last night, my G11 shows the 76

sec error. Overall PE was pretty good, without any PEC.



Today, I pulled the RA worm, and inspected the blocks. The block

farthest from the motor was actually convex on the underside, with

the curvature running the same direction as the worm shaft.



No problem, I thought, I'll just knock off the high spots and flatten

it right out! Unfortunately, the high spot is directly over the

thinnest portion of the bearing block. That portion is almost paper

thin as it is. I couldn't take off nearly enough metal to flatten

the bottom of the block.



I then decided to try shimming the outsides of the block with binder

paper (similar to a website I saw recently, where the owner shimmed

one side of the block.)



My hope is that this will relieve some of the pressure on the bearing

race. I also noticed that the bearing block closest to the motor was

not the right height. I cannot remember at the moment if it was a

little too high or too low.



It seems to me that the quality of the bearing block assembly is much

lower than that of the rest of the mount. Aside from the difficulty

in getting the worm adjusted properly, which is a nuisance, the

blocks themselves seem to be relatively poorly machined, and poorly

aligned.



I'll keep you posted on the PemPro results from tonight.



Regards,



Gary











[Non-text portions of this message have been removed]



----------------------------

#33817 Aug 23, 2007

"I also noticed that the bearing block closest to the motor was

not the right height. I cannot remember at the moment if it was a

little too high or too low."



Do you mean in relation to the motor shaft?





---Frank Rocketman Uroda



----- Original Message -----

From: gary_teamgs

To: Losmandy_users@yahoogroups.com

Sent: Thursday, August 23, 2007 7:57 PM

Subject: [Losmandy_users] PemPro shows the 76 sec error. 1st steps at fixing:





Greetings,

Well, after 5 cycles of PemPro2 last night, my G11 shows the 76

sec error. Overall PE was pretty good, without any PEC.



Today, I pulled the RA worm, and inspected the blocks. The block

farthest from the motor was actually convex on the underside, with

the curvature running the same direction as the worm shaft.



No problem, I thought, I'll just knock off the high spots and flatten

it right out! Unfortunately, the high spot is directly over the

thinnest portion of the bearing block. That portion is almost paper

thin as it is. I couldn't take off nearly enough metal to flatten

the bottom of the block.



I then decided to try shimming the outsides of the block with binder

paper (similar to a website I saw recently, where the owner shimmed

one side of the block.)



My hope is that this will relieve some of the pressure on the bearing

race. I also noticed that the bearing block closest to the motor was

not the right height. I cannot remember at the moment if it was a

little too high or too low.



It seems to me that the quality of the bearing block assembly is much

lower than that of the rest of the mount. Aside from the difficulty

in getting the worm adjusted properly, which is a nuisance, the

blocks themselves seem to be relatively poorly machined, and poorly

aligned.



I'll keep you posted on the PemPro results from tonight.



Regards,



Gary











[Non-text portions of this message have been removed]







----------------------------

#33818 Aug 23, 2007

Correct.. Actually, I just looked at it again, and the motor shaft

appears to be around 1/32" too high.



I will see if the paper shims help, and if so, then I will look at

taking off more of the block.



Thanks Frank!



Gary



--- In Losmandy_users@yahoogroups.com, "Photon Collector"

photoncollector@...> wrote: >

> "I also noticed that the bearing block closest to the motor was

> not the right height. I cannot remember at the moment if it was a

> little too high or too low."

>

> Do you mean in relation to the motor shaft?

>

>

> ---Frank Rocketman Uroda

>

>

> ----- Original Message -----

> From: gary_teamgs

> To: Losmandy_users@yahoogroups.com

> Sent: Thursday, August 23, 2007 7:57 PM

> Subject: [Losmandy_users] PemPro shows the 76 sec error. 1st

steps at fixing: >

>

> Greetings,

> Well, after 5 cycles of PemPro2 last night, my G11 shows the 76

> sec error. Overall PE was pretty good, without any PEC.

>

> Today, I pulled the RA worm, and inspected the blocks. The block

> farthest from the motor was actually convex on the underside,

with > the curvature running the same direction as the worm shaft.

>

> No problem, I thought, I'll just knock off the high spots and

flatten > it right out! Unfortunately, the high spot is directly over the

> thinnest portion of the bearing block. That portion is almost

paper > thin as it is. I couldn't take off nearly enough metal to flatten

> the bottom of the block.

>

> I then decided to try shimming the outsides of the block with

binder > paper (similar to a website I saw recently, where the owner

shimmed > one side of the block.)

>

> My hope is that this will relieve some of the pressure on the

bearing > race. I also noticed that the bearing block closest to the motor

was > not the right height. I cannot remember at the moment if it was a

> little too high or too low.

>

> It seems to me that the quality of the bearing block assembly is

much > lower than that of the rest of the mount. Aside from the

difficulty > in getting the worm adjusted properly, which is a nuisance, the

> blocks themselves seem to be relatively poorly machined, and

poorly > aligned.

>

> I'll keep you posted on the PemPro results from tonight.

>

> Regards,

>

> Gary

>

>

>

>

>

> [Non-text portions of this message have been removed]

>



----------------------------

#33819 Aug 23, 2007

gary_teamgs wrote: > Correct.. Actually, I just looked at it again, and the motor shaft

> appears to be around 1/32" too high.



The Oldham coupler should take care of that, shouldn't it?



--- Mike

--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com



(apologies in advance for any typos or nonsensical phrases. Using

speech-recognition software in my stroke recovery, and I don't always

catch the mistakes it makes.)



----------------------------

#33820 Aug 23, 2007

Mike,



The two shafts MUST intersect at the same point. The coupler is designed

to allow for the shafts to be skewed slightly but there axis of rotation

must intersect at the center of the coupling.



This was a problem with my SkyWalker Servo that required me to shim the

worm blocks slightly.



Steve Izzo



Raleigh Astronomy Club, Raleigh, North Carolina





-----Original Message-----

From: Losmandy_users@yahoogroups.com

[mailto:Losmandy_users@yahoogroups.com] On Behalf Of Mike Dodd

Sent: Thursday, August 23, 2007 9:01 PM

To: Losmandy_users@yahoogroups.com

Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st

steps at fixing:



gary_teamgs wrote: > Correct.. Actually, I just looked at it again, and the motor shaft

> appears to be around 1/32" too high.



The Oldham coupler should take care of that, shouldn't it?



--- Mike

--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com



(apologies in advance for any typos or nonsensical phrases. Using

speech-recognition software in my stroke recovery, and I don't always

catch the mistakes it makes.)







Yahoo! Groups Links



----------------------------

#33822 Aug 23, 2007

Toss the Oldham in the trash and use a helical coupling instead. You can get them from McMaster Carr. While you're at it, get a set of SS ABEC-7 type bearings to go in the blocks.



---Frank Rocketman Uroda



----- Original Message -----

From: Mike Dodd

To: Losmandy_users@yahoogroups.com

Sent: Thursday, August 23, 2007 9:01 PM

Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st steps at fixing:





gary_teamgs wrote:

> Correct.. Actually, I just looked at it again, and the motor shaft

> appears to be around 1/32" too high.



The Oldham coupler should take care of that, shouldn't it?



--- Mike

--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com



(apologies in advance for any typos or nonsensical phrases. Using

speech-recognition software in my stroke recovery, and I don't always

catch the mistakes it makes.)









[Non-text portions of this message have been removed]







----------------------------

#33823 Aug 23, 2007

That's what I thought, Steve. I may have to shim my block as well.



Almost dark enough to get out and try PemPro again.



Gary



--- In Losmandy_users@yahoogroups.com, "Steve Izzo" sdizzo@...>

wrote: >

> Mike,

>

> The two shafts MUST intersect at the same point. The coupler is

designed > to allow for the shafts to be skewed slightly but there axis of

rotation > must intersect at the center of the coupling.

>

> This was a problem with my SkyWalker Servo that required me to shim

the > worm blocks slightly.

>

> Steve Izzo

>

> Raleigh Astronomy Club, Raleigh, North Carolina

>

>

> -----Original Message-----

> From: Losmandy_users@yahoogroups.com

> [mailto:Losmandy_users@yahoogroups.com] On Behalf Of Mike Dodd

> Sent: Thursday, August 23, 2007 9:01 PM

> To: Losmandy_users@yahoogroups.com

> Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st

> steps at fixing:

>

> gary_teamgs wrote:

> > Correct.. Actually, I just looked at it again, and the motor

shaft > > appears to be around 1/32" too high.

>

> The Oldham coupler should take care of that, shouldn't it?

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>

> (apologies in advance for any typos or nonsensical phrases. Using

> speech-recognition software in my stroke recovery, and I don't

always > catch the mistakes it makes.)

>

>

>

> Yahoo! Groups Links

>



----------------------------

#33824 Aug 23, 2007

Don't bother with moving the block up or down. Enlarge the motor bolt holes and move the motor instead.



---Frank Rocketman Uroda



----- Original Message -----

From: gary_teamgs

To: Losmandy_users@yahoogroups.com

Sent: Thursday, August 23, 2007 8:48 PM

Subject: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st steps at fixing:





Correct.. Actually, I just looked at it again, and the motor shaft

appears to be around 1/32" too high.



I will see if the paper shims help, and if so, then I will look at

taking off more of the block.



Thanks Frank!



Gary



--- In Losmandy_users@yahoogroups.com, "Photon Collector"

photoncollector@...> wrote:

>

> "I also noticed that the bearing block closest to the motor was

> not the right height. I cannot remember at the moment if it was a

> little too high or too low."

>

> Do you mean in relation to the motor shaft?

>

>

> ---Frank Rocketman Uroda

>

>

> ----- Original Message -----

> From: gary_teamgs

> To: Losmandy_users@yahoogroups.com

> Sent: Thursday, August 23, 2007 7:57 PM

> Subject: [Losmandy_users] PemPro shows the 76 sec error. 1st

steps at fixing:

>

>

> Greetings,

> Well, after 5 cycles of PemPro2 last night, my G11 shows the 76

> sec error. Overall PE was pretty good, without any PEC.

>

> Today, I pulled the RA worm, and inspected the blocks. The block

> farthest from the motor was actually convex on the underside,

with

> the curvature running the same direction as the worm shaft.

>

> No problem, I thought, I'll just knock off the high spots and

flatten

> it right out! Unfortunately, the high spot is directly over the

> thinnest portion of the bearing block. That portion is almost

paper

> thin as it is. I couldn't take off nearly enough metal to flatten

> the bottom of the block.

>

> I then decided to try shimming the outsides of the block with

binder

> paper (similar to a website I saw recently, where the owner

shimmed

> one side of the block.)

>

> My hope is that this will relieve some of the pressure on the

bearing

> race. I also noticed that the bearing block closest to the motor

was

> not the right height. I cannot remember at the moment if it was a

> little too high or too low.

>

> It seems to me that the quality of the bearing block assembly is

much

> lower than that of the rest of the mount. Aside from the

difficulty

> in getting the worm adjusted properly, which is a nuisance, the

> blocks themselves seem to be relatively poorly machined, and

poorly

> aligned.

>

> I'll keep you posted on the PemPro results from tonight.

>

> Regards,

>

> Gary

>

>

>

>

>

> [Non-text portions of this message have been removed]

>











[Non-text portions of this message have been removed]



----------------------------

#33825 Aug 23, 2007

Frank,

AFAIK McMaster Carr doesn't have one that will fit. This part:

S5904Y-G409-17 from SDP-SI will fit (with 1/8" spacers between the gear

box and RA mounting plate) but will cost 58$ a pop. It did not

dramatically improve my situation, but I am still using it. You can get

bearings from SDP too, save on shipping, 440SS ABEC7: S9912Y-G2562PS2G



Eric



Photon Collector wrote: >

> Toss the Oldham in the trash and use a helical coupling instead. You

> can get them from McMaster Carr. While you're at it, get a set of SS

> ABEC-7 type bearings to go in the blocks.

>

> ---Frank Rocketman Uroda

>

> ----- Original Message -----

> From: Mike Dodd

> To: Losmandy_users@yahoogroups.com

> mailto:Losmandy_users%40yahoogroups.com>

> Sent: Thursday, August 23, 2007 9:01 PM

> Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st

> steps at fixing:

>

> gary_teamgs wrote:

> > Correct.. Actually, I just looked at it again, and the motor shaft

> > appears to be around 1/32" too high.

>

> The Oldham coupler should take care of that, shouldn't it?

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com astronomy.mdodd.com>

>

> (apologies in advance for any typos or nonsensical phrases. Using

> speech-recognition software in my stroke recovery, and I don't always

> catch the mistakes it makes.)

>

> [Non-text portions of this message have been removed]

>

>







----------------------------

#33826 Aug 23, 2007

I got mine from McMaster Carr but I am using ESCAP steppers rather than original Losmandy motors. I didn't think that would make a difference but I guess it does.

I can't swear that the coupling was a big improvement since I made all of the upgrades at once. Collectively, the upgrades made all of the difference in the world. My mount went from useless to superb for around a hundred bucks or so in parts and a few nights of tweaking.



---Frank Rocketman Uroda



----- Original Message -----

From: Eric Benson

To: Losmandy_users@yahoogroups.com

Sent: Thursday, August 23, 2007 11:36 PM

Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st steps at fixing:





Frank,

AFAIK McMaster Carr doesn't have one that will fit. This part:

S5904Y-G409-17 from SDP-SI will fit (with 1/8" spacers between the gear

box and RA mounting plate) but will cost 58$ a pop. It did not

dramatically improve my situation, but I am still using it. You can get

bearings from SDP too, save on shipping, 440SS ABEC7: S9912Y-G2562PS2G



Eric



Photon Collector wrote:

>

> Toss the Oldham in the trash and use a helical coupling instead. You

> can get them from McMaster Carr. While you're at it, get a set of SS

> ABEC-7 type bearings to go in the blocks.

>

> ---Frank Rocketman Uroda

>

> ----- Original Message -----

> From: Mike Dodd

> To: Losmandy_users@yahoogroups.com

> mailto:Losmandy_users%40yahoogroups.com>

> Sent: Thursday, August 23, 2007 9:01 PM

> Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st

> steps at fixing:

>

> gary_teamgs wrote:

> > Correct.. Actually, I just looked at it again, and the motor shaft

> > appears to be around 1/32" too high.

>

> The Oldham coupler should take care of that, shouldn't it?

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com astronomy.mdodd.com>

>

> (apologies in advance for any typos or nonsensical phrases. Using

> speech-recognition software in my stroke recovery, and I don't always

> catch the mistakes it makes.)

>

> [Non-text portions of this message have been removed]

>

>











[Non-text portions of this message have been removed]



----------------------------

#33827 Aug 23, 2007

Thanks for all the great info everyone!



I am in the process of capturing PemPro data as I type. Wireless

networking is great!



I will post the results, and seriously think about more majpr

modifications.



Regards,



Gary





--- In Losmandy_users@yahoogroups.com, "Photon Collector"

photoncollector@...> wrote: >

> I got mine from McMaster Carr but I am using ESCAP steppers rather

than original Losmandy motors. I didn't think that would make a

difference but I guess it does. > I can't swear that the coupling was a big improvement since I made

all of the upgrades at once. Collectively, the upgrades made all of

the difference in the world. My mount went from useless to superb for

around a hundred bucks or so in parts and a few nights of tweaking. >

> ---Frank Rocketman Uroda

>

>

> ----- Original Message -----

> From: Eric Benson

> To: Losmandy_users@yahoogroups.com

> Sent: Thursday, August 23, 2007 11:36 PM

> Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error.

1st steps at fixing: >

>

> Frank,

> AFAIK McMaster Carr doesn't have one that will fit. This part:

> S5904Y-G409-17 from SDP-SI will fit (with 1/8" spacers between

the gear > box and RA mounting plate) but will cost 58$ a pop. It did not

> dramatically improve my situation, but I am still using it. You

can get > bearings from SDP too, save on shipping, 440SS ABEC7: S9912Y-

G2562PS2G >

> Eric

>

> Photon Collector wrote:

> >

> > Toss the Oldham in the trash and use a helical coupling

instead. You > > can get them from McMaster Carr. While you're at it, get a set

of SS > > ABEC-7 type bearings to go in the blocks.

> >

> > ---Frank Rocketman Uroda

> >

> > ----- Original Message -----

> > From: Mike Dodd

> > To: Losmandy_users@yahoogroups.com

> > mailto:Losmandy_users%40yahoogroups.com>

> > Sent: Thursday, August 23, 2007 9:01 PM

> > Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec

error. 1st > > steps at fixing:

> >

> > gary_teamgs wrote:

> > > Correct.. Actually, I just looked at it again, and the motor

shaft > > > appears to be around 1/32" too high.

> >

> > The Oldham coupler should take care of that, shouldn't it?

> >

> > --- Mike

> > --

> >

> > Mike Dodd

> > Montpelier, VA USA

> > astronomy.mdodd.com astronomy.mdodd.com>

> >

> > (apologies in advance for any typos or nonsensical phrases.

Using > > speech-recognition software in my stroke recovery, and I don't

always > > catch the mistakes it makes.)

> >

> > [Non-text portions of this message have been removed]

> >

> >

>

>

>

>

>

> [Non-text portions of this message have been removed]

>







----------------------------

#33829 Aug 24, 2007

> Correct.. Actually, I just looked at it again, and the motor shaft

>> appears to be around 1/32" too high.

>

> The Oldham coupler should take care of that, shouldn't it?

>

Steve Izzo wrote: >

> The two shafts MUST intersect at the same point. The coupler is designed

> to allow for the shafts to be skewed slightly but there axis of rotation

> must intersect at the center of the coupling.



That isn't how I understand the Oldham coupler to work. I believe it's

designed to couple two shafts that are offset AXIALLY. See

www.answers.com/topic/oldham-coupler> Actually, the shafts

shouldn't be skewed; they should be parallel, even if offset axially.



--- Mike

--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com



----------------------------

#33832 Aug 24, 2007

Thanks for that info Mike!

Good to know.



Regards,



Gary

--- In Losmandy_users@yahoogroups.com, Mike Dodd mike@...> wrote:

>

> >> Correct.. Actually, I just looked at it again, and the motor shaft

> >> appears to be around 1/32" too high.

> >

> > The Oldham coupler should take care of that, shouldn't it?

> >

> Steve Izzo wrote:

> >

> > The two shafts MUST intersect at the same point. The coupler is

designed

> > to allow for the shafts to be skewed slightly but there axis of

rotation

> > must intersect at the center of the coupling.

>

> That isn't how I understand the Oldham coupler to work. I believe it's

> designed to couple two shafts that are offset AXIALLY. See

> www.answers.com/topic/oldham-coupler> Actually, the shafts

> shouldn't be skewed; they should be parallel, even if offset axially.

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>



----------------------------

#33837 Aug 24, 2007

One last thing you might try is to order new blocks from Losmandy and

ask them to inspect them for bumps before sending. I ordered a new

pair and they seemed to be better made because there was nu bump on

th ebuttom and the bearing holes weren't as tight.





--- In Losmandy_users@yahoogroups.com, "gary_teamgs"

gary_teamgs@...> wrote: >

> Thanks for all the great info everyone!

>

> I am in the process of capturing PemPro data as I type. Wireless

> networking is great!

>

> I will post the results, and seriously think about more majpr

> modifications.

>

> Regards,

>

> Gary

>

>

> --- In Losmandy_users@yahoogroups.com, "Photon Collector"

> photoncollector@> wrote:

> >

> > I got mine from McMaster Carr but I am using ESCAP steppers

rather > than original Losmandy motors. I didn't think that would make a

> difference but I guess it does.

> > I can't swear that the coupling was a big improvement since I

made > all of the upgrades at once. Collectively, the upgrades made all of

> the difference in the world. My mount went from useless to superb

for > around a hundred bucks or so in parts and a few nights of tweaking.

> >

> > ---Frank Rocketman Uroda

> >

> >

> > ----- Original Message -----

> > From: Eric Benson

> > To: Losmandy_users@yahoogroups.com

> > Sent: Thursday, August 23, 2007 11:36 PM

> > Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec

error. > 1st steps at fixing:

> >

> >

> > Frank,

> > AFAIK McMaster Carr doesn't have one that will fit. This part:

> > S5904Y-G409-17 from SDP-SI will fit (with 1/8" spacers between

> the gear

> > box and RA mounting plate) but will cost 58$ a pop. It did not

> > dramatically improve my situation, but I am still using it. You

> can get

> > bearings from SDP too, save on shipping, 440SS ABEC7: S9912Y-

> G2562PS2G

> >

> > Eric

> >

> > Photon Collector wrote:

> > >

> > > Toss the Oldham in the trash and use a helical coupling

> instead. You

> > > can get them from McMaster Carr. While you're at it, get a

set > of SS

> > > ABEC-7 type bearings to go in the blocks.

> > >

> > > ---Frank Rocketman Uroda

> > >

> > > ----- Original Message -----

> > > From: Mike Dodd

> > > To: Losmandy_users@yahoogroups.com

> > > mailto:Losmandy_users%40yahoogroups.com>

> > > Sent: Thursday, August 23, 2007 9:01 PM

> > > Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec

> error. 1st

> > > steps at fixing:

> > >

> > > gary_teamgs wrote:

> > > > Correct.. Actually, I just looked at it again, and the

motor > shaft

> > > > appears to be around 1/32" too high.

> > >

> > > The Oldham coupler should take care of that, shouldn't it?

> > >

> > > --- Mike

> > > --

> > >

> > > Mike Dodd

> > > Montpelier, VA USA

> > > astronomy.mdodd.com astronomy.mdodd.com>

> > >

> > > (apologies in advance for any typos or nonsensical phrases.

> Using

> > > speech-recognition software in my stroke recovery, and I

don't > always

> > > catch the mistakes it makes.)

> > >

> > > [Non-text portions of this message have been removed]

> > >

> > >

> >

> >

> >

> >

> >

> > [Non-text portions of this message have been removed]

> >

>







----------------------------

#33842 Aug 24, 2007

Photon Collector wrote: > One more VERY critical item is to make sure the blocks are aligned

> with the worm gear axis. The slightest twist (arc-minutes) makes a

> huge difference in PE and spikes.



Wxactly! Very critical.



I found no way to really measure > the twist at such a small scale so I just tapped the block and

> watched the PEMpro data. It was trial and error but in an hour or so

> I got great results. Don't bother with any of these twist adjustments

> until you are sure you have good gear clearance all the way around

> the gear. A little loose (clearance) is better than tight. You'll

> just have to always keep your rig "east heavy". Then always guide at

> less than sidereal speed so the RA motor never stops or reverses

> direction.



Excellent advice, all points.



--- Mike

--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com



----------------------------

#33843 Aug 24, 2007

Wow, tons of good info!



Thanks guys!



I will definitely have to recheck my worm adjustment, as the pempro

data from last night wasn't great. While the 76 sec error seemed to

be lower by around 40% (0.5 arc sec), I think the other errors were

greater. I had difficulty uploading the data to my mount (not really

seeing any reduction in PE) so I will be trying again tonight.



Regards,



Gary



--- In Losmandy_users@yahoogroups.com, Mike Dodd mike@...> wrote:

>

> Photon Collector wrote:

> > One more VERY critical item is to make sure the blocks are aligned

> > with the worm gear axis. The slightest twist (arc-minutes) makes a

> > huge difference in PE and spikes.

>

> Wxactly! Very critical.

>

> I found no way to really measure

> > the twist at such a small scale so I just tapped the block and

> > watched the PEMpro data. It was trial and error but in an hour or so

> > I got great results. Don't bother with any of these twist adjustments

> > until you are sure you have good gear clearance all the way around

> > the gear. A little loose (clearance) is better than tight. You'll

> > just have to always keep your rig "east heavy". Then always guide at

> > less than sidereal speed so the RA motor never stops or reverses

> > direction.

>

> Excellent advice, all points.

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>



----------------------------

#33845 Aug 24, 2007

PEC data is useless.

PEC only works on mounts that don't need it.

If your PE is smooth, the autoguider will take care of it. If you have spikes that are not equal to 1 worm period, the PEC will make it worse. Make your mount work as best you can without needing PEC.



---Frank Rocketman Uroda



----- Original Message -----

From: gary_teamgs

To: Losmandy_users@yahoogroups.com

Sent: Friday, August 24, 2007 4:57 PM

Subject: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st steps at fixing:





Wow, tons of good info!



Thanks guys!



I will definitely have to recheck my worm adjustment, as the pempro

data from last night wasn't great. While the 76 sec error seemed to

be lower by around 40% (0.5 arc sec), I think the other errors were

greater. I had difficulty uploading the data to my mount (not really

seeing any reduction in PE) so I will be trying again tonight.



Regards,



Gary



--- In Losmandy_users@yahoogroups.com, Mike Dodd mike@...> wrote:

>

> Photon Collector wrote:

> > One more VERY critical item is to make sure the blocks are aligned

> > with the worm gear axis. The slightest twist (arc-minutes) makes a

> > huge difference in PE and spikes.

>

> Wxactly! Very critical.

>

> I found no way to really measure

> > the twist at such a small scale so I just tapped the block and

> > watched the PEMpro data. It was trial and error but in an hour or so

> > I got great results. Don't bother with any of these twist adjustments

> > until you are sure you have good gear clearance all the way around

> > the gear. A little loose (clearance) is better than tight. You'll

> > just have to always keep your rig "east heavy". Then always guide at

> > less than sidereal speed so the RA motor never stops or reverses

> > direction.

>

> Excellent advice, all points.

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>











[Non-text portions of this message have been removed]



----------------------------

#33847 Aug 24, 2007

Mike, That's a cool animation I had not seen that one before, too bad

that isn't what is in our G11. The "Oldham" coupler made by TinyMite

www.renbrandt.com/tiny_order.html> has square slots that hold

cylindrical shafts, so the coupler allows the disks to slide with

respect to each other and twist to accommodate offset and angle

mismatch. I never thought the sliding motion could ever be very smooth

since it is just a steel to nylon interface. But it seems to work for

a lot of users?!? So should we start calling the GM8/G11 coupler an

enhanced Oldham coupler ;)



Eric



--- In Losmandy_users@yahoogroups.com, Mike Dodd mike@...> wrote:

>

> >> Correct.. Actually, I just looked at it again, and the motor shaft

> >> appears to be around 1/32" too high.

> >

> > The Oldham coupler should take care of that, shouldn't it?

> >

> Steve Izzo wrote:

> >

> > The two shafts MUST intersect at the same point. The coupler is

designed

> > to allow for the shafts to be skewed slightly but there axis of

rotation

> > must intersect at the center of the coupling.

>

> That isn't how I understand the Oldham coupler to work. I believe it's

> designed to couple two shafts that are offset AXIALLY. See

> www.answers.com/topic/oldham-coupler> Actually, the shafts

> shouldn't be skewed; they should be parallel, even if offset axially.

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>







----------------------------

#33848 Aug 24, 2007

This was exactly what I did (enlarge the motor housing holes) in

response to the coupler not being in-line when viewed from the side.

This was also suggested by Scott. It immediately fixed my binding,

which I could see was happening by just watching the rotation while

running the motor. The coupler would absolutely seize up. Now it's

very smooth.



Bill Shaheen

Gold Canyon, AZ

USA





--- In Losmandy_users@yahoogroups.com, "Photon Collector"

photoncollector@...> wrote: >

> Don't bother with moving the block up or down. Enlarge the motor

bolt holes and move the motor instead. >

> ---Frank Rocketman Uroda

>

>

> ----- Original Message -----

> From: gary_teamgs

> To: Losmandy_users@yahoogroups.com

> Sent: Thursday, August 23, 2007 8:48 PM

> Subject: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st

steps at fixing: >

>

> Correct.. Actually, I just looked at it again, and the motor

shaft > appears to be around 1/32" too high.

>

> I will see if the paper shims help, and if so, then I will look

at > taking off more of the block.

>

> Thanks Frank!

>

> Gary

>

> --- In Losmandy_users@yahoogroups.com, "Photon Collector"

> photoncollector@> wrote:

> >

> > "I also noticed that the bearing block closest to the motor was

> > not the right height. I cannot remember at the moment if it was

a > > little too high or too low."

> >

> > Do you mean in relation to the motor shaft?

> >

> >

> > ---Frank Rocketman Uroda

> >

> >

> > ----- Original Message -----

> > From: gary_teamgs

> > To: Losmandy_users@yahoogroups.com

> > Sent: Thursday, August 23, 2007 7:57 PM

> > Subject: [Losmandy_users] PemPro shows the 76 sec error. 1st

> steps at fixing:

> >

> >

> > Greetings,

> > Well, after 5 cycles of PemPro2 last night, my G11 shows the 76

> > sec error. Overall PE was pretty good, without any PEC.

> >

> > Today, I pulled the RA worm, and inspected the blocks. The

block > > farthest from the motor was actually convex on the underside,

> with

> > the curvature running the same direction as the worm shaft.

> >

> > No problem, I thought, I'll just knock off the high spots and

> flatten

> > it right out! Unfortunately, the high spot is directly over the

> > thinnest portion of the bearing block. That portion is almost

> paper

> > thin as it is. I couldn't take off nearly enough metal to

flatten > > the bottom of the block.

> >

> > I then decided to try shimming the outsides of the block with

> binder

> > paper (similar to a website I saw recently, where the owner

> shimmed

> > one side of the block.)

> >

> > My hope is that this will relieve some of the pressure on the

> bearing

> > race. I also noticed that the bearing block closest to the

motor > was

> > not the right height. I cannot remember at the moment if it was

a > > little too high or too low.

> >

> > It seems to me that the quality of the bearing block assembly

is > much

> > lower than that of the rest of the mount. Aside from the

> difficulty

> > in getting the worm adjusted properly, which is a nuisance, the

> > blocks themselves seem to be relatively poorly machined, and

> poorly

> > aligned.

> >

> > I'll keep you posted on the PemPro results from tonight.

> >

> > Regards,

> >

> > Gary

> >

> >

> >

> >

> >

> > [Non-text portions of this message have been removed]

> >

>

>

>

>

>

> [Non-text portions of this message have been removed]

>



----------------------------

#33853 Aug 24, 2007

PEC data is useless.

> PEC only works on mounts that don't need it.

> If your PE is smooth, the autoguider will take care of it. If

> you have spikes that are not equal to 1 worm period, the PEC

> will make it worse. Make your mount work as best you can

> without needing PEC.



Consider this... any time the autoguider has to move the scope to recenter the

guidestar your image has _already_ been "damaged" (i.e. stellar FWHM increases).

When using a properly functioning PEC better images will result when the

autoguider has to work less to keep the star centered.



Most users with mounts with very low PE like the Paramount ME and AP1200's

use PEC, so I don't agree with your statement: "PEC only works on mounts

that don't need it". Using PEC will allow you to take longer autoguider

integrations. This may be necessary if you have an SBIG camera and want

to use the built in autoguider CCD to take narrowband images or even

broadband images in sparse stellar fields.



Of course if the 76 sec error is present in the G11, that is not correctable

with PEC, but at least the true periodic error fundamentals can mostly be

reduced.



-Ray Gralak







----------------------------

#33854 Aug 24, 2007

Ok, but consider this.......

You have a smooth PE except for a spike that does not correspond to a single worm cycle. During the learn phase, the PEC sees the spike and corrects for it. Later, it is correcting this spike once for every worm cycle whether the real spike is there or not. So now you have the real spike plus a mis-timed spike correction from the PEC. In reality, you will have several spikes of various magnitudes and the PEC will be making corrections where none are needed. This becomes a real mess, really fast.

The big $$$ mounts have a smooth PE (they better have for 10k+!) so there are no spikes present for the PEC to record and (attempt to) correct. But since the PE is so smooth to begin with, the auto guider will take care of the drift anyway.

I guess software CAN cure some problems with mechanical issues but making the mechanical parts work the best they can is by far the best solution.

Would your image look better if your system were at focus during imaging or would it be better out-of-focus but with sharpening?



---Frank Rocketman Uroda



----- Original Message -----

From: Ray Gralak

To: Losmandy_users@yahoogroups.com

Sent: Saturday, August 25, 2007 12:57 AM

Subject: RE: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st steps at fixing:







> PEC data is useless.

> PEC only works on mounts that don't need it.

> If your PE is smooth, the autoguider will take care of it. If

> you have spikes that are not equal to 1 worm period, the PEC

> will make it worse. Make your mount work as best you can

> without needing PEC.



Consider this... any time the autoguider has to move the scope to recenter the

guidestar your image has _already_ been "damaged" (i.e. stellar FWHM increases).

When using a properly functioning PEC better images will result when the

autoguider has to work less to keep the star centered.



Most users with mounts with very low PE like the Paramount ME and AP1200's

use PEC, so I don't agree with your statement: "PEC only works on mounts

that don't need it". Using PEC will allow you to take longer autoguider

integrations. This may be necessary if you have an SBIG camera and want

to use the built in autoguider CCD to take narrowband images or even

broadband images in sparse stellar fields.



Of course if the 76 sec error is present in the G11, that is not correctable

with PEC, but at least the true periodic error fundamentals can mostly be

reduced.



-Ray Gralak











[Non-text portions of this message have been removed]



----------------------------

#33855 Aug 24, 2007

You have a smooth PE except for a spike that does not

> correspond to a single worm cycle. During the learn phase,

> the PEC sees the spike and corrects for it. Later, it is

> correcting this spike once for every worm cycle whether the

> real spike is there or not. So now you have the real spike

> plus a mis-timed spike correction from the PEC. In reality,

> you will have several spikes of various magnitudes and the

> PEC will be making corrections where none are needed. This

> becomes a real mess, really fast.



Yes, that's a good reason why you do NOT want to use an autoguider

to program PEC and one of the original reasons why I developed PEMPro.

PEMPro samples multiple worm cycles and removes the spikes. It also

allows one to easily adjust for the phase delay, which is another

reason why using an autoguider can result in a less accurate PEC curve.



And note that even if there are spikes you would see them anyway

with PEC off. But at least some of the movement from PE can be

removed and that will result in better images.

> The big $$$ mounts have a smooth PE (they better have for

> 10k+!) so there are no spikes present for the PEC to record

> and (attempt to) correct. But since the PE is so smooth to

> begin with, the auto guider will take care of the drift anyway.

> I guess software CAN cure some problems with mechanical

> issues but making the mechanical parts work the best they can

> is by far the best solution.



But no matter what you do your chances of getting a worm gear with

"0" PEC is almost impossible even with a $10K mount. But some mounts

less costly have attained corrected 1" PE.

> Would your image look better if your system were at focus

> during imaging or would it be better out-of-focus but with sharpening?



Would your image look better if it tracked perfectly or if the

autoguider had to make movements every 5 seconds? :-)



-Ray













>

> ---Frank Rocketman Uroda

>

> ----- Original Message -----

> From: Ray Gralak

> To: Losmandy_users@yahoogroups.com

> mailto:Losmandy_users%40yahoogroups.com>

> Sent: Saturday, August 25, 2007 12:57 AM

> Subject: RE: [Losmandy_users] Re: PemPro shows the 76 sec

> error. 1st steps at fixing:

>

> > PEC data is useless.

> > PEC only works on mounts that don't need it.

> > If your PE is smooth, the autoguider will take care of it. If

> > you have spikes that are not equal to 1 worm period, the PEC

> > will make it worse. Make your mount work as best you can

> > without needing PEC.

>

> Consider this... any time the autoguider has to move the

> scope to recenter the

> guidestar your image has _already_ been "damaged" (i.e.

> stellar FWHM increases).

> When using a properly functioning PEC better images will

> result when the

> autoguider has to work less to keep the star centered.

>

> Most users with mounts with very low PE like the Paramount ME

> and AP1200's

> use PEC, so I don't agree with your statement: "PEC only

> works on mounts

> that don't need it". Using PEC will allow you to take longer

> autoguider

> integrations. This may be necessary if you have an SBIG

> camera and want

> to use the built in autoguider CCD to take narrowband images or even

> broadband images in sparse stellar fields.

>

> Of course if the 76 sec error is present in the G11, that is

> not correctable

> with PEC, but at least the true periodic error fundamentals

> can mostly be

> reduced.

>

> -Ray Gralak

>

> [Non-text portions of this message have been removed]

>

>

>

>

>







----------------------------

#33856 Aug 24, 2007

I guess software CAN cure some problems with mechanical

> issues but making the mechanical parts work the best they can

> is by far the best solution.



BTW, I'm not saying that you should not try to make the mechanicals work the

best possible. I'm just saying that if you want the best images possible you

should use whatever means necessary to reduce tracking errors at the scope (and

that includes PEC IMHO).



-Ray



----------------------------

#33857 Aug 25, 2007

Photon Collector wrote: > Ok, but consider this....... You have a smooth PE except for a spike

> that does not correspond to a single worm cycle. During the learn

> phase, the PEC sees the spike and corrects for it. Later, it is

> correcting this spike once for every worm cycle whether the real

> spike is there or not. So now you have the real spike plus a

> mis-timed spike correction from the PEC.



That's why you use PEMPro, and turn off the 3X fundamental when building

the PE curve. This eliminates the 76-second term from the curve.

I



--- Mike

--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com



----------------------------

#33864 Aug 25, 2007

Great stuff everyone!



I hadn't thought about turning off the third fundamental.



BTW, with all my "machining" on the worm block, I succeeded in making

the 76 Sec. error worse! :D



It may be due to twisting of the worm blocks during adjustment. I

will investigate further.



I am also thinking about switching the block with a dec block, if

that one looks better.



After 8 cycles of PemPro, and loading up the curve, the PE is still

relatively high, at +- 8 arcsec, but appears very regular. When I

refined the curve, the overall error was lessend, but it became more

erratic. I think I will post the results on the PEmPro forum.



However, my guiding performance in AstroArt seems no better than with

my LX200, with noticible ovalness in the RA axis, when viewing the

guider plots. I think that I must need some adjustments in the guide

parameters as well.



I will be back at it again Monday night, as I have been busy this

weekend. Good thing the moon is shining brightly, because I think

that I have at least a few more nights of tweaking. :D



THanks again everyone, I really appreciate the assistance.



Regards,



Gary



--- In Losmandy_users@yahoogroups.com, "Photon Collector"

photoncollector@...> wrote: >

> ".........PEMPro samples multiple worm cycles and removes the

spikes. It also > allows one to easily adjust for the phase delay..........."

>

> I stand corrected.

> My original point was to make the mount track as well as possible

by tuning the mechanism. >

> BTW, there is no way I could have tuned my mount as well as I did

without the feedback displayed by PEMPro. It is an indispensable tool. >

> ---Frank Rocketman Uroda

>

>

> ----- Original Message -----

> From: Ray Gralak

> To: Losmandy_users@yahoogroups.com

> Sent: Saturday, August 25, 2007 2:03 AM

> Subject: RE: [Losmandy_users] Re: PemPro shows the 76 sec error.

1st steps at fixing: >

>

> > You have a smooth PE except for a spike that does not

> > correspond to a single worm cycle. During the learn phase,

> > the PEC sees the spike and corrects for it. Later, it is

> > correcting this spike once for every worm cycle whether the

> > real spike is there or not. So now you have the real spike

> > plus a mis-timed spike correction from the PEC. In reality,

> > you will have several spikes of various magnitudes and the

> > PEC will be making corrections where none are needed. This

> > becomes a real mess, really fast.

>

> Yes, that's a good reason why you do NOT want to use an autoguider

> to program PEC and one of the original reasons why I developed

PEMPro. > PEMPro samples multiple worm cycles and removes the spikes. It

also > allows one to easily adjust for the phase delay, which is another

> reason why using an autoguider can result in a less accurate PEC

curve. >

> And note that even if there are spikes you would see them anyway

> with PEC off. But at least some of the movement from PE can be

> removed and that will result in better images.

>

> > The big $$$ mounts have a smooth PE (they better have for

> > 10k+!) so there are no spikes present for the PEC to record

> > and (attempt to) correct. But since the PE is so smooth to

> > begin with, the auto guider will take care of the drift anyway.

> > I guess software CAN cure some problems with mechanical

> > issues but making the mechanical parts work the best they can

> > is by far the best solution.

>

> But no matter what you do your chances of getting a worm gear with

> "0" PEC is almost impossible even with a $10K mount. But some

mounts > less costly have attained corrected 1" PE.

>

> > Would your image look better if your system were at focus

> > during imaging or would it be better out-of-focus but with

sharpening? >

> Would your image look better if it tracked perfectly or if the

> autoguider had to make movements every 5 seconds? :-)

>

> -Ray

>

> >

> > ---Frank Rocketman Uroda

> >

> > ----- Original Message -----

> > From: Ray Gralak

> > To: Losmandy_users@yahoogroups.com

> > mailto:Losmandy_users%40yahoogroups.com>

> > Sent: Saturday, August 25, 2007 12:57 AM

> > Subject: RE: [Losmandy_users] Re: PemPro shows the 76 sec

> > error. 1st steps at fixing:

> >

> > > PEC data is useless.

> > > PEC only works on mounts that don't need it.

> > > If your PE is smooth, the autoguider will take care of it. If

> > > you have spikes that are not equal to 1 worm period, the PEC

> > > will make it worse. Make your mount work as best you can

> > > without needing PEC.

> >

> > Consider this... any time the autoguider has to move the

> > scope to recenter the

> > guidestar your image has _already_ been "damaged" (i.e.

> > stellar FWHM increases).

> > When using a properly functioning PEC better images will

> > result when the

> > autoguider has to work less to keep the star centered.

> >

> > Most users with mounts with very low PE like the Paramount ME

> > and AP1200's

> > use PEC, so I don't agree with your statement: "PEC only

> > works on mounts

> > that don't need it". Using PEC will allow you to take longer

> > autoguider

> > integrations. This may be necessary if you have an SBIG

> > camera and want

> > to use the built in autoguider CCD to take narrowband images or

even > > broadband images in sparse stellar fields.

> >

> > Of course if the 76 sec error is present in the G11, that is

> > not correctable

> > with PEC, but at least the true periodic error fundamentals

> > can mostly be

> > reduced.

> >

> > -Ray Gralak

> >

> > [Non-text portions of this message have been removed]

> >

> >

> >

> >

> >

>

>

>

>

>

> [Non-text portions of this message have been removed]

>







----------------------------

#33867 Aug 26, 2007

gary_teamgs wrote: > BTW, with all my "machining" on the worm block, I succeeded in making

> the 76 Sec. error worse! :D

>

> It may be due to twisting of the worm blocks during adjustment.



I suspect it is. My 76-second error is very sensitive to block twisting.

My theory is that any twist forces the balls against the raceway walls,

and this force varies depending on where in their travel the balls are.

Hencem the 76s error.



--- Mike

--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com



----------------------------

#33868 Aug 26, 2007

Thanks!



Sigh...



That modified worm block is starting to look REALLY good right now! :D



Gary

--- In Losmandy_users@yahoogroups.com, Mike Dodd mike@...> wrote:

>

> gary_teamgs wrote:

> > BTW, with all my "machining" on the worm block, I succeeded in

making

> > the 76 Sec. error worse! :D

> >

> > It may be due to twisting of the worm blocks during adjustment.

>

> I suspect it is. My 76-second error is very sensitive to block

twisting.

> My theory is that any twist forces the balls against the raceway

walls,

> and this force varies depending on where in their travel the balls

are.

> Hencem the 76s error.

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>



----------------------------

#33869 Aug 26, 2007

Hi Frank,



May I ask you where did you get the Escap motors and what kind of

gearing did you use (I suppose you don't have a Gemini). Also, how did

you attach the new motor to the mount bearing plate?



I still have the Saia motors on my GM-8 (with the 1:150 gearing ratio)

and I'm considering to use Escap motor too.



Thanks.



Claudio



--- In Losmandy_users@yahoogroups.com, "Photon Collector"

photoncollector@...> wrote: >

> I got mine from McMaster Carr but I am using ESCAP steppers rather

than original Losmandy motors. I didn't think that would make a

difference but I guess it does. > I can't swear that the coupling was a big improvement since I made

all of the upgrades at once. Collectively, the upgrades made all of

the difference in the world. My mount went from useless to superb for

around a hundred bucks or so in parts and a few nights of tweaking. >

> ---Frank Rocketman Uroda

>

>

> ----- Original Message -----

> From: Eric Benson

> To: Losmandy_users@yahoogroups.com

> Sent: Thursday, August 23, 2007 11:36 PM

> Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error.

1st steps at fixing: >

>

> Frank,

> AFAIK McMaster Carr doesn't have one that will fit. This part:

> S5904Y-G409-17 from SDP-SI will fit (with 1/8" spacers between the

gear > box and RA mounting plate) but will cost 58$ a pop. It did not

> dramatically improve my situation, but I am still using it. You

can get > bearings from SDP too, save on shipping, 440SS ABEC7: S9912Y-G2562PS2G

>

> Eric

>

> Photon Collector wrote:

> >

> > Toss the Oldham in the trash and use a helical coupling instead.

You > > can get them from McMaster Carr. While you're at it, get a set

of SS > > ABEC-7 type bearings to go in the blocks.

> >

> > ---Frank Rocketman Uroda

> >

> > ----- Original Message -----

> > From: Mike Dodd

> > To: Losmandy_users@yahoogroups.com

> > mailto:Losmandy_users%40yahoogroups.com>

> > Sent: Thursday, August 23, 2007 9:01 PM

> > Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error.

1st > > steps at fixing:

> >

> > gary_teamgs wrote:

> > > Correct.. Actually, I just looked at it again, and the motor shaft

> > > appears to be around 1/32" too high.

> >

> > The Oldham coupler should take care of that, shouldn't it?

> >

> > --- Mike

> > --

> >

> > Mike Dodd

> > Montpelier, VA USA

> > astronomy.mdodd.com astronomy.mdodd.com>

> >

> > (apologies in advance for any typos or nonsensical phrases. Using

> > speech-recognition software in my stroke recovery, and I don't

always > > catch the mistakes it makes.)

> >

> > [Non-text portions of this message have been removed]

> >

> >

>

>

>

>

>

> [Non-text portions of this message have been removed]

>



----------------------------

#33870 Aug 26, 2007

Claudio,

I bought the ESCAP motors, G-11 mounting kit, and FS2 Goto computer from Astro Electronic in Germany.

www.astro-electronic.de/



I have never had a problem with these motor stalling or burning up, even when my gear was WAY too tight. But I could tell by the sound that the motors were working hard to get past the tight spot. I even fell asleep one night and my mount crashed into itself for over an hour before I woke up. There was no damage what so ever even though the clutches were pretty tight. I'm very happy with these motors.

My good friend in Kansas, Mike Sisk, recommended the motors and FS2 to me. He uses the same system on his 24.5" SCT.

At the time the exchange rate was favorable to the USA so all of the above was actually cheaper than a Gemini. But that was not my main concern. Now the Euro is way above the USD.



---Frank Rocketman Uroda



----- Original Message -----

From: schinazic

To: Losmandy_users@yahoogroups.com

Sent: Sunday, August 26, 2007 2:23 PM

Subject: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st steps at fixing:





Hi Frank,



May I ask you where did you get the Escap motors and what kind of

gearing did you use (I suppose you don't have a Gemini). Also, how did

you attach the new motor to the mount bearing plate?



I still have the Saia motors on my GM-8 (with the 1:150 gearing ratio)

and I'm considering to use Escap motor too.



Thanks.



Claudio



--- In Losmandy_users@yahoogroups.com, "Photon Collector"

photoncollector@...> wrote:

>

> I got mine from McMaster Carr but I am using ESCAP steppers rather

than original Losmandy motors. I didn't think that would make a

difference but I guess it does.

> I can't swear that the coupling was a big improvement since I made

all of the upgrades at once. Collectively, the upgrades made all of

the difference in the world. My mount went from useless to superb for

around a hundred bucks or so in parts and a few nights of tweaking.

>

> ---Frank Rocketman Uroda

>

>

> ----- Original Message -----

> From: Eric Benson

> To: Losmandy_users@yahoogroups.com

> Sent: Thursday, August 23, 2007 11:36 PM

> Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error.

1st steps at fixing:

>

>

> Frank,

> AFAIK McMaster Carr doesn't have one that will fit. This part:

> S5904Y-G409-17 from SDP-SI will fit (with 1/8" spacers between the

gear

> box and RA mounting plate) but will cost 58$ a pop. It did not

> dramatically improve my situation, but I am still using it. You

can get

> bearings from SDP too, save on shipping, 440SS ABEC7: S9912Y-G2562PS2G

>

> Eric

>

> Photon Collector wrote:

> >

> > Toss the Oldham in the trash and use a helical coupling instead.

You

> > can get them from McMaster Carr. While you're at it, get a set

of SS

> > ABEC-7 type bearings to go in the blocks.

> >

> > ---Frank Rocketman Uroda

> >

> > ----- Original Message -----

> > From: Mike Dodd

> > To: Losmandy_users@yahoogroups.com

> > mailto:Losmandy_users%40yahoogroups.com>

> > Sent: Thursday, August 23, 2007 9:01 PM

> > Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error.

1st

> > steps at fixing:

> >

> > gary_teamgs wrote:

> > > Correct.. Actually, I just looked at it again, and the motor shaft

> > > appears to be around 1/32" too high.

> >

> > The Oldham coupler should take care of that, shouldn't it?

> >

> > --- Mike

> > --

> >

> > Mike Dodd

> > Montpelier, VA USA

> > astronomy.mdodd.com astronomy.mdodd.com>

> >

> > (apologies in advance for any typos or nonsensical phrases. Using

> > speech-recognition software in my stroke recovery, and I don't

always

> > catch the mistakes it makes.)

> >

> > [Non-text portions of this message have been removed]

> >

> >

>

>

>

>

>

> [Non-text portions of this message have been removed]

>











[Non-text portions of this message have been removed]







----------------------------

#33871 Aug 26, 2007

gary_teamgs wrote: > Thanks!

>

> Sigh...

>

> That modified worm block is starting to look REALLY good right now! :D



not necessarily. Take a look in my alum in the photos section to see how

to use the stock metal worm shield as a bracket to align the bearing

blocks. I think this was originally Rainer's idea. Essentially it

requires drilling and tapping some holes in the bearing blocks for some

screws, and then drilling matching clearance holes in the metal shield.

The shield is milled aluminum, and does a great job of aligning the

bearing blocks.



--- Mike

--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com



----------------------------

#33872 Aug 26, 2007

Mike,

The sides of the bearing blocks are not machined. The four sides are part of the raw extrusion and may not be flat or square. Only the top and bottom of the blocks are machined. Using any sort of straight edge to align the blocks will not necessarily work as intended.

From what I can tell by inspecting the blocks, they are made from square bar stock. The bar is placed in a 4-jaw chuck and the bottom nub is machined, drilled, and tapped. Then the block is cut off to length and the bearing pocket is machined with a mill as a secondary operation. OR, if the lathe has live tooling, the bearing pocket is bored out while still in the lathe before the block is cut off. In either case, the 4 sides of the block are raw extrusions.

Before I figured this out, I did try using a straight edge to align both blocks and the results were horrible. The bearing pockets are not necessarily parallel to the sides of the blocks.



---Frank Rocketman Uroda



----- Original Message -----

From: Mike Dodd

To: Losmandy_users@yahoogroups.com

Sent: Sunday, August 26, 2007 6:36 PM

Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error. 1st steps at fixing:





gary_teamgs wrote:

> Thanks!

>

> Sigh...

>

> That modified worm block is starting to look REALLY good right now! :D



not necessarily. Take a look in my alum in the photos section to see how

to use the stock metal worm shield as a bracket to align the bearing

blocks. I think this was originally Rainer's idea. Essentially it

requires drilling and tapping some holes in the bearing blocks for some

screws, and then drilling matching clearance holes in the metal shield.

The shield is milled aluminum, and does a great job of aligning the

bearing blocks.



--- Mike

--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com









[Non-text portions of this message have been removed]



----------------------------

#33873 Aug 26, 2007

Mike,



How do you turn the 3x component off?



Brian



--- In Losmandy_users@yahoogroups.com, Mike Dodd mike@...> wrote:

>

> Photon Collector wrote:

> > Ok, but consider this....... You have a smooth PE except for a

spike

> > that does not correspond to a single worm cycle. During the learn

> > phase, the PEC sees the spike and corrects for it. Later, it is

> > correcting this spike once for every worm cycle whether the real

> > spike is there or not. So now you have the real spike plus a

> > mis-timed spike correction from the PEC.

>

> That's why you use PEMPro, and turn off the 3X fundamental when

building

> the PE curve. This eliminates the 76-second term from the curve.

> I

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>



----------------------------

#33874 Aug 26, 2007

Mike,



How do you turn the 3x component off?



Brian



--- In Losmandy_users@yahoogroups.com, Mike Dodd mike@...> wrote:

>

> Photon Collector wrote:

> > Ok, but consider this....... You have a smooth PE except for a

spike

> > that does not correspond to a single worm cycle. During the learn

> > phase, the PEC sees the spike and corrects for it. Later, it is

> > correcting this spike once for every worm cycle whether the real

> > spike is there or not. So now you have the real spike plus a

> > mis-timed spike correction from the PEC.

>

> That's why you use PEMPro, and turn off the 3X fundamental when

building

> the PE curve. This eliminates the 76-second term from the curve.

> I

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>



----------------------------

#33875 Aug 27, 2007

Hey Brian,

I haven't yet investigated that the third fundamental did indeed

correspond with the 76 sec error spike, but here is how you can remove

fundamentals from the curve creation:



When in the Create PE screen, you will see three sections. The top is

the graph of the fitted curve, the middle is the FFT waveform

analysis, and the bottom is the data points.



Click the dropdown of the fitted curve, and change the graph type to,

I believe, Frequency Spectrum with seconds. This will show the

fundamentals in graphical form, with the timeline. You can then see

on which fundamental the 76 sec error falls.



You then look at the middle section, and uncheck the corresponding

fundamental.



At least that is how I understand it! :D



Gary



--- In Losmandy_users@yahoogroups.com, "astroimage2002" brian@...> wrote:

>

> Mike,

>

> How do you turn the 3x component off?

>

> Brian

>

>

> --- In Losmandy_users@yahoogroups.com, Mike Dodd mike@> wrote:

> >

> > Photon Collector wrote:

> > > Ok, but consider this....... You have a smooth PE except for a

> spike

> > > that does not correspond to a single worm cycle. During the learn

> > > phase, the PEC sees the spike and corrects for it. Later, it is

> > > correcting this spike once for every worm cycle whether the real

> > > spike is there or not. So now you have the real spike plus a

> > > mis-timed spike correction from the PEC.

> >

> > That's why you use PEMPro, and turn off the 3X fundamental when

> building

> > the PE curve. This eliminates the 76-second term from the curve.

> > I

> >

> > --- Mike

> > --

> >

> > Mike Dodd

> > Montpelier, VA USA

> > astronomy.mdodd.com

> >

>







----------------------------

#33876 Aug 27, 2007

Well that sucks!



I had been thinking about a straightedge as Mike had suggested.



I may have to see how much replacement blocks are. Maybe the new ones

will be better. I will not give up though!!!! :D



Looks like more tweaking in store tonight!



Gary



--- In Losmandy_users@yahoogroups.com, "Photon Collector"

photoncollector@...> wrote: >

> Mike,

> The sides of the bearing blocks are not machined. The four sides are

part of the raw extrusion and may not be flat or square. Only the top

and bottom of the blocks are machined. Using any sort of straight edge

to align the blocks will not necessarily work as intended. > From what I can tell by inspecting the blocks, they are made from

square bar stock. The bar is placed in a 4-jaw chuck and the bottom

nub is machined, drilled, and tapped. Then the block is cut off to

length and the bearing pocket is machined with a mill as a secondary

operation. OR, if the lathe has live tooling, the bearing pocket is

bored out while still in the lathe before the block is cut off. In

either case, the 4 sides of the block are raw extrusions. > Before I figured this out, I did try using a straight edge to align

both blocks and the results were horrible. The bearing pockets are not

necessarily parallel to the sides of the blocks. >

> ---Frank Rocketman Uroda

>

>

> ----- Original Message -----

> From: Mike Dodd

> To: Losmandy_users@yahoogroups.com

> Sent: Sunday, August 26, 2007 6:36 PM

> Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error.

1st steps at fixing: >

>

> gary_teamgs wrote:

> > Thanks!

> >

> > Sigh...

> >

> > That modified worm block is starting to look REALLY good right

now! :D >

> not necessarily. Take a look in my alum in the photos section to

see how > to use the stock metal worm shield as a bracket to align the bearing

> blocks. I think this was originally Rainer's idea. Essentially it

> requires drilling and tapping some holes in the bearing blocks for

some > screws, and then drilling matching clearance holes in the metal

shield. > The shield is milled aluminum, and does a great job of aligning the

> bearing blocks.

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>

>

>

>

> [Non-text portions of this message have been removed]

>



----------------------------

#33878 Aug 27, 2007

Well, after 5 cycles of PemPro2 last night, my G11 shows the 76

>sec error. Overall PE was pretty good, without any PEC.



I just attempted to upgrade from PEMPro 1 to PEMPro 2. Despite the website

claiming there was the opportunity to pay less than the full purchase price, I

was charged the full purchase price, despite it being merely an upgrade.

Frankly, I trust that a program written by Ray Gralak will be good. However, I

have grave doubts about the method of online purchase through CCDWare.



I note the comment of CCDWare's, Richard Bennion, that, "We are getting many

emails and posts regarding problems and ordering with our online commerce

vendor." I'd suggest that people hold off purchasing until the problems are

resolved.



Greg



----------------------------

#33880 Aug 27, 2007

astroimage2002 wrote: > Mike,

>

> How do you turn the 3x component off?



on the Analyze tab of the Create PE curve window, un-check the 3.000

fundamental frequency box, then watch the resulting curve characteristics.



--- Mike



--



Mike Dodd

Montpelier, VA USA

astronomy.mdodd.com



----------------------------

#33884 Aug 27, 2007

Ray,



In my opinion, that's a poorly designed web page. If the top is broken into

product category, the upgrade for each should be included in the break-up.



Greg



-----Original Message-----

From: Losmandy_users@yahoogroups.com [mailto:Losmandy_users@yahoogroups.com] On

Behalf Of Ray Gralak

Sent: Tuesday, 28 August 2007 4:07 AM

To: Losmandy_users@yahoogroups.com

Cc: rbennion@...

Subject: RE: [Losmandy_users] PemPro shows the 76 sec error. 1st steps at

fixing:



Hi Greg,



The CCDWare purchase page (www.ccdware.com/buy/) has two PEMPro items in

it. The first one, near the top, is for a full license. The second, if you

scroll down, is under "Software Upgrades", and is the upgrade for existing

users. That was the item you needed to select.



That said, I'm copying this to Richard Bennion, who should be able to fix this

situation.



Sorry for the confusion!



-Ray Gralak

> -----Original Message-----

> From: Losmandy_users@yahoogroups.com

> [mailto:Losmandy_users@yahoogroups.com] On Behalf Of Greg Crawford

> Sent: Monday, August 27, 2007 9:24 AM

> To: Losmandy_users@yahoogroups.com

> Subject: RE: [Losmandy_users] PemPro shows the 76 sec error.

> 1st steps at fixing:

>

> >Well, after 5 cycles of PemPro2 last night, my G11 shows the 76

> >sec error. Overall PE was pretty good, without any PEC.

>

> I just attempted to upgrade from PEMPro 1 to PEMPro 2.

> Despite the website

> claiming there was the opportunity to pay less than the full

> purchase price, I

> was charged the full purchase price, despite it being merely

> an upgrade.

> Frankly, I trust that a program written by Ray Gralak will be

> good. However, I

> have grave doubts about the method of online purchase through

> CCDWare.

>

> I note the comment of CCDWare's, Richard Bennion, that, "We

> are getting many

> emails and posts regarding problems and ordering with our

> online commerce

> vendor." I'd suggest that people hold off purchasing until

> the problems are

> resolved.

>

> Greg

>

>

>

>

>









Yahoo! Groups Links







----------------------------

#33885 Aug 27, 2007

Frank -



re: "The bearing pockets are not necessarily parallel to the sides of

the blocks." It seems to me that this is solved, at least to some

extent, with the procedure of "pinching" the 2 blocks together. I

had a good bit of success in doing this. I squeezed the 2 blocks

between my thumb and middle finger, at the same time applying some

mild pressure toward the worm wheel and tightening the whole

configuration from the bottom.



Also, it may explain why I have since had difficulty re-attaching

the "decorative" cover plate. When I tighten one side, the other

pops loose, if applied to tightly.



Would you agree?



Bill Shaheen

Gold Canyon, AZ

USA





--- In Losmandy_users@yahoogroups.com, "Photon Collector"

photoncollector@...> wrote: >

> Mike,

> The sides of the bearing blocks are not machined. The four sides

are part of the raw extrusion and may not be flat or square. Only the

top and bottom of the blocks are machined. Using any sort of straight

edge to align the blocks will not necessarily work as intended. > From what I can tell by inspecting the blocks, they are made from

square bar stock. The bar is placed in a 4-jaw chuck and the bottom

nub is machined, drilled, and tapped. Then the block is cut off to

length and the bearing pocket is machined with a mill as a secondary

operation. OR, if the lathe has live tooling, the bearing pocket is

bored out while still in the lathe before the block is cut off. In

either case, the 4 sides of the block are raw extrusions. > Before I figured this out, I did try using a straight edge to align

both blocks and the results were horrible. The bearing pockets are

not necessarily parallel to the sides of the blocks. >

> ---Frank Rocketman Uroda

>

>

> ----- Original Message -----

> From: Mike Dodd

> To: Losmandy_users@yahoogroups.com

> Sent: Sunday, August 26, 2007 6:36 PM

> Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error.

1st steps at fixing: >

>

> gary_teamgs wrote:

> > Thanks!

> >

> > Sigh...

> >

> > That modified worm block is starting to look REALLY good right

now! :D >

> not necessarily. Take a look in my alum in the photos section to

see how > to use the stock metal worm shield as a bracket to align the

bearing > blocks. I think this was originally Rainer's idea. Essentially it

> requires drilling and tapping some holes in the bearing blocks

for some > screws, and then drilling matching clearance holes in the metal

shield. > The shield is milled aluminum, and does a great job of aligning

the > bearing blocks.

>

> --- Mike

> --

>

> Mike Dodd

> Montpelier, VA USA

> astronomy.mdodd.com

>

>

>

>

> [Non-text portions of this message have been removed]

>



----------------------------

#33886 Aug 28, 2007

I may give that method a shot Bill!



Gary



--- In Losmandy_users@yahoogroups.com, "William J. Shaheen"

wjshaheen@...> wrote: >

> Frank -

>

> re: "The bearing pockets are not necessarily parallel to the sides of

> the blocks." It seems to me that this is solved, at least to some

> extent, with the procedure of "pinching" the 2 blocks together. I

> had a good bit of success in doing this. I squeezed the 2 blocks

> between my thumb and middle finger, at the same time applying some

> mild pressure toward the worm wheel and tightening the whole

> configuration from the bottom.

>

> Also, it may explain why I have since had difficulty re-attaching

> the "decorative" cover plate. When I tighten one side, the other

> pops loose, if applied to tightly.

>

> Would you agree?

>

> Bill Shaheen

> Gold Canyon, AZ

> USA

>

>

> --- In Losmandy_users@yahoogroups.com, "Photon Collector"

> photoncollector@> wrote:

> >

> > Mike,

> > The sides of the bearing blocks are not machined. The four sides

> are part of the raw extrusion and may not be flat or square. Only the

> top and bottom of the blocks are machined. Using any sort of straight

> edge to align the blocks will not necessarily work as intended.

> > From what I can tell by inspecting the blocks, they are made from

> square bar stock. The bar is placed in a 4-jaw chuck and the bottom

> nub is machined, drilled, and tapped. Then the block is cut off to

> length and the bearing pocket is machined with a mill as a secondary

> operation. OR, if the lathe has live tooling, the bearing pocket is

> bored out while still in the lathe before the block is cut off. In

> either case, the 4 sides of the block are raw extrusions.

> > Before I figured this out, I did try using a straight edge to align

> both blocks and the results were horrible. The bearing pockets are

> not necessarily parallel to the sides of the blocks.

> >

> > ---Frank Rocketman Uroda

> >

> >

> > ----- Original Message -----

> > From: Mike Dodd

> > To: Losmandy_users@yahoogroups.com

> > Sent: Sunday, August 26, 2007 6:36 PM

> > Subject: Re: [Losmandy_users] Re: PemPro shows the 76 sec error.

> 1st steps at fixing:

> >

> >

> > gary_teamgs wrote:

> > > Thanks!

> > >

> > > Sigh...

> > >

> > > That modified worm block is starting to look REALLY good right

> now! :D

> >

> > not necessarily. Take a look in my alum in the photos section to

> see how

> > to use the stock metal worm shield as a bracket to align the

> bearing

> > blocks. I think this was originally Rainer's idea. Essentially it

> > requires drilling and tapping some holes in the bearing blocks

> for some

> > screws, and then drilling matching clearance holes in the metal

> shield.

> > The shield is milled aluminum, and does a great job of aligning

> the

> > bearing blocks.

> >

> > --- Mike

> > --

> >

> > Mike Dodd

> > Montpelier, VA USA

> > astronomy.mdodd.com

> >

> >

> >

> >

> > [Non-text portions of this message have been removed]

> >

>







----------------------------

#33898 Aug 29, 2007

*** SUCCESS ***



After finally deciding to ream out the bearing pockets, I reduced the

76 sec. error to around 0.4 arcseconds. WooHoo!



I found that when I removed the gear and block assembly, the block

farthest from the motor was noticeably tighter when spinning with my

fingers while holding the worm shaft. The "good" block would turn

around 10-20 revolutions after being spun, while the "bad" block would

turn less than 10 revolutions. After drilling an access hole, then

pressing out the bearings, the block in question did indeed have a

much tighter race pocket. After reaming out the pockets, the block in

question now spun with the same freedom as the other block.



I replaced the assembly, pinching the blocks together to try and keep

them aligned, and tightened them down. Backlash was too great, but I

didn't want to fiddle with it any more for the time being.



After running PemPro, I was pleasantly surprised!



Here is a link to the graphs(click the G11 mods link on the left):



www.teamgs.org/equipment_frame.htm





I didn't have time to actually program the curve into my mount (issues

with a reversed curve), but I hope to do that tonight.



I now have more error around the 1st fundamental that I have to

investigate, but I am very happy. I need to see if the guiding

scatter plots are now tighter and rounder, and not the oval plots that

I am used to seeing!



Thanks for all the GREAT advice everyone! Now if we can just get a

modified assembly from Losmandy that addresses these issues!



Regards,



Gary

















--- In Losmandy_users@yahoogroups.com, "gary_teamgs" gary_teamgs@...>

wrote: >

> Greetings,

> Well, after 5 cycles of PemPro2 last night, my G11 shows the 76

> sec error. Overall PE was pretty good, without any PEC.

>

> Today, I pulled the RA worm, and inspected the blocks. The block

> farthest from the motor was actually convex on the underside, with

> the curvature running the same direction as the worm shaft.

>

> No problem, I thought, I'll just knock off the high spots and flatten

> it right out! Unfortunately, the high spot is directly over the

> thinnest portion of the bearing block. That portion is almost paper

> thin as it is. I couldn't take off nearly enough metal to flatten

> the bottom of the block.

>

> I then decided to try shimming the outsides of the block with binder

> paper (similar to a website I saw recently, where the owner shimmed

> one side of the block.)

>

> My hope is that this will relieve some of the pressure on the bearing

> race. I also noticed that the bearing block closest to the motor was

> not the right height. I cannot remember at the moment if it was a

> little too high or too low.

>

> It seems to me that the quality of the bearing block assembly is much

> lower than that of the rest of the mount. Aside from the difficulty

> in getting the worm adjusted properly, which is a nuisance, the

> blocks themselves seem to be relatively poorly machined, and poorly

> aligned.

>

> I'll keep you posted on the PemPro results from tonight.

>

> Regards,

>

> Gary

>



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