Topics

Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

Cheng-Yang Tan
 

Hi guys,
   While contemplating whether to grease my gears, I discovered that I can rock my RA "left and right" in the Park 3 position of my Mach1GTO. I can just barely see it on the RA marks but can definitely feel it. I can't do the same rocking motion on my AP1100. Note: Mount is powered OFF when I do the rock.

  Should I do the "Checking and Adjusting the gearbox backstops in RA and Dec" from page 32 of the manual?

Thanks!

cytan

Charles Thompson
 

I would wait for more knowledgeable people to chime in because it can be a couple things. In my case it was gear mesh and was easily fixed by doing a re-mesh procedure from the instructions.





Thanks,
Charles

Sent from mobile device.


-------- Original message --------
From: "Cheng-Yang Tan via groups.io" <cytan299@...>
Date: 5/16/20 1:34 PM (GMT-06:00)
To: main@ap-gto.groups.io
Subject: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

Hi guys,
   While contemplating whether to grease my gears, I discovered that I can rock my RA "left and right" in the Park 3 position of my Mach1GTO. I can just barely see it on the RA marks but can definitely feel it. I can't do the same rocking motion on my AP1100. Note: Mount is powered OFF when I do the rock.

  Should I do the "Checking and Adjusting the gearbox backstops in RA and Dec" from page 32 of the manual?

Thanks!

cytan

Peter Bresler
 

I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

Cheng-Yang Tan
 

HI Peter,
   I haven't done anything yet. I'm waiting for Rolando or George to give some advice. Perhaps the very small rocking in RA is normal or needs to be adjusted. Like I had posted earlier, I don't see or feel the rocking motion on my AP1100 on either axis.

cytan

On Sunday, May 17, 2020, 10:47:08 AM CDT, Peter Bresler via groups.io <pabresler@...> wrote:


I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

Frank Widmann
 

AP has a procedure for adjusting the mesh between the worm and the worm gear that will eliminate the play in either axis. The play is easier to detect in RA because of the large moment arm provided by the counterweight shaft. Declination should be checked to if it has been a while. The procedure is available on line under Support.

Frank

On May 17, 2020, at 8:47 AM, Peter Bresler via groups.io <PABresler@...> wrote:

I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

Bill Long
 

It's important to know which Mach 1 it is.


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Frank Widmann via groups.io <fjwidmann@...>
Sent: Sunday, May 17, 2020 12:42 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?
 
AP has a procedure for adjusting the mesh between the worm and the worm gear that will eliminate the play in either axis. The play is easier to detect in RA because of the large moment arm provided by the counterweight shaft. Declination should be checked to if it has been a while. The procedure is available on line under Support.

Frank

On May 17, 2020, at 8:47 AM, Peter Bresler via groups.io <PABresler@...> wrote:

I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

Cheng-Yang Tan
 

My Mach1GTO is from the final batch made. So it should be this one:


I'm waiting for the official word before going ahead with it.

cytan

On Sunday, May 17, 2020, 02:45:48 PM CDT, Bill Long <bill@...> wrote:


It's important to know which Mach 1 it is.


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Frank Widmann via groups.io <fjwidmann@...>
Sent: Sunday, May 17, 2020 12:42 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?
 
AP has a procedure for adjusting the mesh between the worm and the worm gear that will eliminate the play in either axis. The play is easier to detect in RA because of the large moment arm provided by the counterweight shaft. Declination should be checked to if it has been a while. The procedure is available on line under Support.

Frank

On May 17, 2020, at 8:47 AM, Peter Bresler via groups.io <PABresler@...> wrote:

I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

Bill Long
 

Then it's the backstop. It's largely irrelevant though. I would leave it alone.


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Cheng-Yang Tan via groups.io <cytan299@...>
Sent: Sunday, May 17, 2020 12:49 PM
To: Frank Widmann via groups. io <fjwidmann@...>; main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?
 
My Mach1GTO is from the final batch made. So it should be this one:


I'm waiting for the official word before going ahead with it.

cytan

On Sunday, May 17, 2020, 02:45:48 PM CDT, Bill Long <bill@...> wrote:


It's important to know which Mach 1 it is.


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Frank Widmann via groups.io <fjwidmann@...>
Sent: Sunday, May 17, 2020 12:42 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?
 
AP has a procedure for adjusting the mesh between the worm and the worm gear that will eliminate the play in either axis. The play is easier to detect in RA because of the large moment arm provided by the counterweight shaft. Declination should be checked to if it has been a while. The procedure is available on line under Support.

Frank

On May 17, 2020, at 8:47 AM, Peter Bresler via groups.io <PABresler@...> wrote:

I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

uncarollo2 <chris1011@aol.com>
 

Worm tooth mesh is only one of several possible reasons why the RA axis could rock back and forth. One reason, other than worm mesh, is that the end play nut has come loose and needs to be tightened up. This nut holds the worm bearings in place and can be reached by removing the small round cover on the side of the gearbox.

The problem with trying to get answers on a user group is that there is never any meaningful information, we only hear about the symptoms. However, if you call George by phone, he can run you thru a series of checks that can pinpoint what is really happening. George is available to help AP users on regular business hours, so either give him a call or send him an e-mail and set up a time when you can be at your mount.

Rolando

-----Original Message-----
From: Frank Widmann via groups.io <fjwidmann@...>
To: main@ap-gto.groups.io
Sent: Sun, May 17, 2020 2:42 pm
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

AP has a procedure for adjusting the mesh between the worm and the worm gear that will eliminate the play in either axis. The play is easier to detect in RA because of the large moment arm provided by the counterweight shaft. Declination should be checked to if it has been a while. The procedure is available on line under Support.

Frank

On May 17, 2020, at 8:47 AM, Peter Bresler via groups.io <PABresler@...> wrote:

I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

uncarollo2 <chris1011@aol.com>
 

The backstop does not prevent the axis from rocking back and forth unless you put a huge amount of force on the axis that causes the worm teeth to lift out of the worm wheel. Checking axis backlash should never require huge force to try to move the axis, rather it should be just finger pressure back and forth. If it doesn't move with finger pressure, then all is well. However, if finger pressure does move the axis, then it is an indication that the worm bearings are loose, or even that the main bearing end play nut has come loose.

Give George a call.

Rolando



-----Original Message-----
From: Bill Long <bill@...>
To: Cheng-Yang Tan via groups. io <cytan299@...>; Frank Widmann via groups. io <fjwidmann@...>; main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Sun, May 17, 2020 2:57 pm
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

Then it's the backstop. It's largely irrelevant though. I would leave it alone.


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Cheng-Yang Tan via groups.io <cytan299@...>
Sent: Sunday, May 17, 2020 12:49 PM
To: Frank Widmann via groups. io <fjwidmann@...>; main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?
 
My Mach1GTO is from the final batch made. So it should be this one:


I'm waiting for the official word before going ahead with it.

cytan

On Sunday, May 17, 2020, 02:45:48 PM CDT, Bill Long <bill@...> wrote:


It's important to know which Mach 1 it is.


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Frank Widmann via groups.io <fjwidmann@...>
Sent: Sunday, May 17, 2020 12:42 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?
 
AP has a procedure for adjusting the mesh between the worm and the worm gear that will eliminate the play in either axis. The play is easier to detect in RA because of the large moment arm provided by the counterweight shaft. Declination should be checked to if it has been a while. The procedure is available on line under Support.

Frank

On May 17, 2020, at 8:47 AM, Peter Bresler via groups.io <PABresler@...> wrote:

I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

Bill Long
 

I should have clarified, the PDF is what I was referring to. Not the solution to the problem being related to it.



From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of uncarollo2 <chris1011@...> via groups.io <chris1011@...>
Sent: Sunday, May 17, 2020 1:05 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>; george@... <george@...>
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?
 
The backstop does not prevent the axis from rocking back and forth unless you put a huge amount of force on the axis that causes the worm teeth to lift out of the worm wheel. Checking axis backlash should never require huge force to try to move the axis, rather it should be just finger pressure back and forth. If it doesn't move with finger pressure, then all is well. However, if finger pressure does move the axis, then it is an indication that the worm bearings are loose, or even that the main bearing end play nut has come loose.

Give George a call.

Rolando



-----Original Message-----
From: Bill Long <bill@...>
To: Cheng-Yang Tan via groups. io <cytan299@...>; Frank Widmann via groups. io <fjwidmann@...>; main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Sun, May 17, 2020 2:57 pm
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

Then it's the backstop. It's largely irrelevant though. I would leave it alone.


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Cheng-Yang Tan via groups.io <cytan299@...>
Sent: Sunday, May 17, 2020 12:49 PM
To: Frank Widmann via groups. io <fjwidmann@...>; main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?
 
My Mach1GTO is from the final batch made. So it should be this one:


I'm waiting for the official word before going ahead with it.

cytan

On Sunday, May 17, 2020, 02:45:48 PM CDT, Bill Long <bill@...> wrote:


It's important to know which Mach 1 it is.


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Frank Widmann via groups.io <fjwidmann@...>
Sent: Sunday, May 17, 2020 12:42 PM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?
 
AP has a procedure for adjusting the mesh between the worm and the worm gear that will eliminate the play in either axis. The play is easier to detect in RA because of the large moment arm provided by the counterweight shaft. Declination should be checked to if it has been a while. The procedure is available on line under Support.

Frank

On May 17, 2020, at 8:47 AM, Peter Bresler via groups.io <PABresler@...> wrote:

I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

Cheng-Yang Tan
 

Hi Rolando,
   Thanks for the info. That's the reason why I didn't do anything. I'll call George tomorrow.

cytan

On Sunday, May 17, 2020, 03:05:11 PM CDT, uncarollo2 <chris1011@...> via groups.io <chris1011@...> wrote:


Worm tooth mesh is only one of several possible reasons why the RA axis could rock back and forth. One reason, other than worm mesh, is that the end play nut has come loose and needs to be tightened up. This nut holds the worm bearings in place and can be reached by removing the small round cover on the side of the gearbox.

The problem with trying to get answers on a user group is that there is never any meaningful information, we only hear about the symptoms. However, if you call George by phone, he can run you thru a series of checks that can pinpoint what is really happening. George is available to help AP users on regular business hours, so either give him a call or send him an e-mail and set up a time when you can be at your mount.

Rolando

-----Original Message-----
From: Frank Widmann via groups.io <fjwidmann@...>
To: main@ap-gto.groups.io
Sent: Sun, May 17, 2020 2:42 pm
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

AP has a procedure for adjusting the mesh between the worm and the worm gear that will eliminate the play in either axis. The play is easier to detect in RA because of the large moment arm provided by the counterweight shaft. Declination should be checked to if it has been a while. The procedure is available on line under Support.

Frank

On May 17, 2020, at 8:47 AM, Peter Bresler via groups.io <PABresler@...> wrote:

I also noted some play in the RA in my Mach1. I tried the lever adjustment but it made no change. The entire gear box moves a little.

Gabe Shaughnessy
 

I had a similar issue to this with my AP1100.  I adjusted the backstop, but that didn't help.  I followed some additional adjustment instructions given by Roland here. Worked like a charm!

Gabe

uncarollo2 <chris1011@aol.com>
 

Thank you for posting that.

Rolando



-----Original Message-----
From: Gabe Shaughnessy <gshaughnessy@...>
To: main@ap-gto.groups.io
Sent: Sun, May 17, 2020 3:22 pm
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

I had a similar issue to this with my AP1100.  I adjusted the backstop, but that didn't help.  I followed some additional adjustment instructions given by Roland here. Worked like a charm!

Gabe

Cheng-Yang Tan
 

Hi guys,
   I did what Rolando posted in the instructions below. I could actually turn the nut by 1/4 turn! I didn't have a spanner wrench and so I made a fixture to fit into the two holes. I first tightened using just my fingers and then used a pair of pliers to do the final tightening. I  don't think I had a lot of leverage and so I don't think I overtightened the nut. However, if I did, can overtightening cause problems?

  Even after tightening the nut, there was still a small RA play, I think < 10 mils that I both feel and see. George then asked me to adjust the backstop. And voila, the RA play disappeared.

  It's fixed now (unless I managed to screw up something else) but I am really surprised that I could turn the nut by 1/4 turn.

  Thanks to everybody who posted here, Rolando and George.

cytan

On Sunday, May 17, 2020, 03:28:09 PM CDT, uncarollo2 <chris1011@...> via groups.io <chris1011@...> wrote:


Thank you for posting that.

Rolando



-----Original Message-----
From: Gabe Shaughnessy <gshaughnessy@...>
To: main@ap-gto.groups.io
Sent: Sun, May 17, 2020 3:22 pm
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

I had a similar issue to this with my AP1100.  I adjusted the backstop, but that didn't help.  I followed some additional adjustment instructions given by Roland here. Worked like a charm!

Gabe

uncarollo2 <chris1011@aol.com>
 

You can tighten that nut without causing any problems. The bearings will take up to 15 inch-lb of torque. Heavy vibration during shipping might loosen the nut. Put a dab of RTV at the periphery of the nut to keep it from loosening.

Rolando



-----Original Message-----
From: Cheng-Yang Tan via groups.io <cytan299@...>
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Sent: Tue, May 19, 2020 5:59 pm
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

Hi guys,
   I did what Rolando posted in the instructions below. I could actually turn the nut by 1/4 turn! I didn't have a spanner wrench and so I made a fixture to fit into the two holes. I first tightened using just my fingers and then used a pair of pliers to do the final tightening. I  don't think I had a lot of leverage and so I don't think I overtightened the nut. However, if I did, can overtightening cause problems?

  Even after tightening the nut, there was still a small RA play, I think < 10 mils that I both feel and see. George then asked me to adjust the backstop. And voila, the RA play disappeared.

  It's fixed now (unless I managed to screw up something else) but I am really surprised that I could turn the nut by 1/4 turn.

  Thanks to everybody who posted here, Rolando and George.

cytan

On Sunday, May 17, 2020, 03:28:09 PM CDT, uncarollo2 <chris1011@...> via groups.io <chris1011@...> wrote:


Thank you for posting that.

Rolando



-----Original Message-----
From: Gabe Shaughnessy <gshaughnessy@...>
To: main@ap-gto.groups.io
Sent: Sun, May 17, 2020 3:22 pm
Subject: Re: [ap-gto] Advice needed: I can rock RA in Mach1GTO (very small), should I adjust?

I had a similar issue to this with my AP1100.  I adjusted the backstop, but that didn't help.  I followed some additional adjustment instructions given by Roland here. Worked like a charm!

Gabe