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Gotcha.? Thank you.? From the feel of things, my worms appear to be right around the middle, so that should afford me a little bit of room for error.? And like you were saying, I can always adjust the center before torquing down those bolts.? Looks like a pretty simple job, I hope.? Worst case, I can always go back to the existing holes.?? Looks like Ive got a nice little project lined up.? I'll probably leave it as is for the next few days to try and sneak in some more imaging before the moon starts getting big and bright, but after that, I'll tear down and do the following:

- Drill and countersink the opposite three hole pattern in the RA worm mounting plate.
- Re-print the mounting brackets in PETG filament (stronger, better heat resistance).? Ill leave both motors on the tucked side.
- Finally unstick the frozen worm wheel on the DEC axis, clean and re-lube.
- Drill and tap two 6-32 holes on the edge of the mounting plate (opposite the motor mount holes).? This provision will be an attachment point for a DIY spring loaded OPWB.
- Drill and tap the top and sides of the extra 2-piece worm blocks I ordered.
- Fabricate a simple OPWB from aluminum 90? angle stock.

I'll take lots of picture and post results, assuming everything goes to plan.

Thanks again,
-Tony

Tony - I'd say it's 'pretty' tight, I'd estimate maybe 0.5mm of clearance (very rough guess from last time I had it apart).? In fact, I tried to make use of that wiggle room on the DEC axis to move the base plate as close as I could to the brass bushing since, no matter how much I tried to tighten the mesh of the worm to reduce backlash, I could never create a stall condition (as a reference point to back away from when loosening the mesh).? So moving the plate in principle brought the worm closer, though I don't think that experiment did anything meaningful.

Keith

I had been wondering this same question...

so with the 3 hole pattern you can’t do 180 like on the current production mounts without additional work, but could you do 120°?

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Ahhh!!!? OK, Got it.? Do you happen to know if the plate is a tight fit to the large brass bushing?? Or are the screws themselves used to locate the worm plate.? If the large bore locates the plate, then drilling a new bolt pattern and countersinking the holes is relatively trivial.? However if those are shoulder bolts used to locate the plate, then its obviously more involved.? I'll probably have to strip the mount down myself and start exploring, but this image gives me a pretty good idea now.? Thank you!

-Tony

I've attached a photo of the worm mounting plate from my G11 which hopefully shows you the 3 countersunk screws I mean (bearing block holes are to the right just out of view).? The rest can be also be seen on this disassembly page?? So because of the triangular screw pattern, you can't rotate the whole plate by 180 degrees.

Keith

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Hi Keith - It didn't occur to me either at first.? Took a while of fiddling with the motor brackets I have while wondering how Losmandy fit their motors without hitting the altitude knob, then finally noticed they moved them to the back side of the mount.

I'm not sure which 3 countersunk bolts you mean other than maybe for the worm cover.? I would think the cover would not matter since it would rotate in place, along with the rest of mounting plate, worm blocks, and motor.? I'm just not sure how the worm mounting plate attaches to the rest of the RA housing.? Is it a smooth 2 inch bore?? Is it a spline?? Are there hidden bolts?? Is it possible that its all one solid piece?? I really don't know of any images showing the housing taken apart.? But if it is possible, it would afford some extra mounting options.

Thanks,
-Tony

Yes, that was a very creative solution, David. You probably saved some money by not shipping a big piece of iron across the Atlantic Ocean. For my mount I use the standard 7, 11 and 21 pound weights in combination. The smallest I use for the final balance adjustments. Please let us know how your setup works out for you when you get everything assembled.?

Best Regards,

John

Hi Tony.? I'm embarrassed to say that until you pointed it out, I'd never noticed Losmandy swapped sides on the newer tuck-motor mounts (I have an older)!? I don't think you can reverse the plate on your G11 since the 3 screw holes in the plate are countersunk, and therefore the plate can only rotated by 180 deg (not flipped) which would misalign the screw holes.

Keith

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Hi Michael, Thanks for your help once again.

I don't mean to put the worm drive under the mounting plate.?? I'm looking to rotate the mounting plate itself 180 degrees so the motor is at the back of the RA instead of the front.? This G11 is an OnStep conversion, currently using rockmover's 3D printed brackets.? Since the tucked stepper motor interferes with the altitude knob, I would love to move the worm and motor to the back side of the mount like the newer style G11 seems to have.

Ive attached an image to show you what I'm working with.?? The bracket was designed to have the motor on the inboard side, but because of the interference with the alt knob, I had to move it to the outboard side.? It works fine, but if I can clean it up by running it tucked on the back side of the mount, even better.? I just don't know if its possible to disassemble the RA housing and orient the worm towards the back of the mount.

FWIW, I do plan on fabricating my own spring loaded OPW as my next project.? Ive already ordered a spare set of worm blocks to mess with, that way I can always return to stock.

On a completely unrelated note, is there any reason you don't recommend simply heating the bearing blocks in a toaster oven to get the bearings out?? Five minutes at 325 and the stock bearings dropped right out (from gravity) and new ones slid right in.?? I found it to be much much easier than fabbing up a makeshift puller.

Thanks again,
-Tony

Hi all, got a quick question.?? I have an old G11 with the two piece worm blocks, where the RA motor is located on the bottom (towards the altitude knob).? Is it possible to switch the RA worm and motor location to the top like the newer tucked motors?? If so, how do you disassemble the housing to rotate the worm mounting plate?? I suspect it isn't possible and would require a new worm mounting plate, if not a complete RA housing.? But I figured I might as well ask.

Thanks for any advice,
-Tony

Just found some Jet-Lube MP-50 on Ebay. $20 for a pint plus shipping in the US. Previously I was finding larger containers at higher prices. I am planning to use this on my next worm relubrication - whenever that might be. Surprisingly this is very viscous and sticky stuff - almost like peanut butter; but of course, since it's labeled a paste. Since MP-50 is used just for the worm and ring gears this amount should be a lifetime supply:).

Brian - good point "I?prefer to keep my Losmandy powered from a? ground source, it's one less cable that may catch"

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Jim W
Phoenix, AZ. USA

Thanks Brian and Michael.

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Jim W
Phoenix, AZ. USA

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I know the max current depends on voltage (12 vs 15) and overall load on the mount but has anybody measured the current while slewing using a 12 volt supply?? I am trying to determine if the Pegasus Pocket Powerbox can drive my equipment.



GM811G while slewing - ?
Pegasus FocusCube2 - 0.6 amps
ASI2600MC Pro at max TEC - 3 amps
Dew heaters 2 each - 2.5 amps
Pegasus Pocket Powerbox - 0.5 amps

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Jim W
Phoenix, AZ. USA

Hi Paul

How will Gemini respond when it gets a pulse duration that is shorter than the minimum movement for a given gear/servo combination? Will it?

a) ignore the pulse?
b) issue a minimum pulse??

Likewise, will all longer pulses be "rounded up" to the shortest combination of steps corresponding to the requested pulse duration or truncated down?

Reading this thread made me go back and look at the guide logs for my GM811 Dec axis and a "quantization" error may explain some behavior. I am seeing.

Soy el tipo de espa?a, yo me hice mi contrapeso con cemento con el nucleo de 10 kg de acero recubierto de caucho, utilize unas mancuernas viejas, me hice un molde, distribuí los pesos y los cemente con fibra de poliuretano, es solido como una roca, para el perno de apriete a la barra utilicé una rosca la cual corte en dos y estan unidas con un iman de neodimio, asi la parte interior que toca la barra de contrapeso no gira y no crea marcas.

?

Hahaha that's easy...near the vets memorial......wink wink wink

I threw it away it was rusty......hahaha
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Brendan