Re: Clutch Knobs vs. the Gearbox Release Levers

Roland Christen

"Keeping the mount perfectly steady while engaging the gearbox release was a challenge at times and this is when I remember feeling the teeth raking across the worm more than once before it would fully engage."
If you have your mount set up, try this little experiment:

1) Send the mount to Park3.
2) while holding the rear of your scope, release the RA gearbox lever.
3) now let go of the scope.

Did the scope suddenly move? I bet not. Notice how stable the scope is even with the gears fully released. Even if it was unbalanced it would not move, unless you begin to swing the scope a bit from the Park 3 position. You can now manually move the axis to the horizontal position to do fine balance. once that is finished, return the mount back to Park3 position.

4) Now re-lock the gears with the lever only 1/2 way to the full lock position. Gently rock the axis back and forth by a very small minute amount until you can hear the gears engage naturally. Once they do, you will not feel any motion as you apply a tiny amount of pressure back and forth. When you feel no motion, turn the lever the rest of the way to fully locked position.

5) With scope still in Park3, release the DEC gearbox lever. Did the scope suddenly move? I bet not, and again note how stable the scope is, even if it was not perfectly balanced.
6) Now move the Dec axis to the Park2 position (horizontal). In this position you can do a fine Dec balance.
7) move the scope back to Park3 position and lock the lever in 2 steps as above.

Do this with your Mach1 mount in order to get a feel for how things should be done to prevent any kind of problems with the gears if you have unbalanced load. If you really don't know how badly out of balance you are, you can get pretty close to balance by loosening the clutches and doing a rough balance first. Once you have done that, you can do a fine balance by taking the gears out of mesh. You won't have to worry about wild swings when the axes are disengaged.

Roland Christen

-----Original Message-----
From: Andrew Jones <andjones132@...>
Sent: Fri, Feb 26, 2021 2:19 pm
Subject: Re: [ap-gto] Clutch Knobs vs. the Gearbox Release Levers

Hi Rolando.

Thank you for your response and it is very good to hear you do service your mounts after the sale. Like I said, I don't mind spending the money for a world class mount, but I need to know that if the mount ever needs to be serviced and it is beyond my skill level that I can send it back to AP get it serviced. 

Also, thank you for explaining a bit more what it takes to damage the gears and for letting me know that I should only be using the gearbox release from Park 3. It is probably in the manual somewhere, but I never knew that the gearbox release should only be used in Park 3. This is great to know. 

Regarding my my Mach1, yes, I have felt the gears rake across teeth when I engaging the release lever a couple of times, but I have never forced anything. This was mainly a problem when I first got the Mach1 and I had a 11" EdgeHD OTA fully loaded with imaging gear, which required over 60lbs of counter weights. Keeping the mount perfectly steady while engaging the gearbox release was a challenge at times and this is when I remember feeling the teeth raking across the worm more than once before it would fully engage. Of course, I did not know I should only be using the release levers from Park 3 which probably made the situation worse. That said, I never force it to engage, so maybe the gears are still OK. If memory serves me correctly, I think I only ever had this happen on the DEC Axis so based on what you told me I should still be OK even if I did slightly damage the gear. George sent me a note asking me to send him a screen shot of my guiding for 7 mins with aggressiveness set to zero. He seemed to indicate that he would be able to tell if the worm gear has been damaged based on this. Are there any other techniques to check if the worm gears have been damaged? I would like to check both Axis just to make sure they are OK.

The Mach1 was my first mount, so I made a lot of mistakes over the years as I learned how to use this type of mount. Now I need to clean up my mistakes and fix any issues so that I can get many more years of service out of the mount. Plus if I ever sell the mount I don't want to pass on a damaged mount to someone who then might blame AP for issues caused by me. The current plan is for the Mach1 to become my portable mount once the 1100 show up. I want to be able to do solar imaging and I found out recently that imaging the sun from inside a dome is a bad idea due to the sun heading up the dome during the day. So the Mach1 will make for a perfect platform for my Lunt solar scope that I can setup out in the yard away from any radiant heat sources. 

Thanks again for all your help and support.

Andrew J

Roland Christen

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