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Hello,
I have my older CG-11 apart and noticed with the dec axis off, and the clutch loose, the RA axis is actually hard to return at three points along its full revolution. Is this normal? Seems like the shaft might have been dropped by a prior owner or it’s somehow not straight. I have it stripped down like in the photo and am turning it by hand.

If it’s normal it seems easy to change out, I see a set screw holding it on the that top plate the dec boots to. Is it something I can get from Losmandy?

Also, I don’t have the altitude locking bolts, I figure Losmandy can add that if I wanted it, seems difficult to DIY

Thanks in advance,
Mike

Hi Mike,
I don't have an answer for you, there I know there are members here who do.
So hang on until the cavalry arrives.
--
SonnyE


(I suggest viewed in full screen)

Hi Mike

is your worm gear engaged? If you are comfortable with disassembly you might try disengaging your worm gear and rotating the RA shaft to isolate if it's the shaft itself or something related to the gearing

Mike- I recently purchased a second hand G11 and found the RA axis very difficult to move with the gears removed. I removed the RA head, removed, cleaned and regreased the bearings and it solved it completely. I carefully inspected all of the bearings and if any looked anything other than perfect I was prepared to order replacements. In my case, they all looked good and cleaning and grease was all that was needed. If you're at all mechanically inclined I'd recommend going one level deeper into your mount and see what you find.

I did just this in the afternoon. I cleaned everything pretty well. But I found when I removed the worm the entire assembly of ring gear and everything spun freely. When I put the worm back in the RA assembly would have that stickiness again. It seems to be the clutch, even fully loosened it’s a bit sticky. Make it harder to balance in RA. Dec spins freely, just assumed the RA axis would as well.

Mike

Hi Mike

I"m not sure at what point of re-assembly you found the RA is a bit sticky. did you put your telescope back on??

>>>When I put the worm back in the RA assembly would have that stickiness again

this sounds to me like it could be a worm gear meshing too tight. i'm not sure what else you saw the leads you to the clutch

Brian

Possibly a bit of a tight spot in one of the needle bearings. You can rince them with WD40, then turp, dry thoroughly and regrease lightly. Sliding the RA axis in the other way (knob side) can help re-aligning them as well, if you have three. Or maybe your end plate is not square to the axis anymore (sag) or the shaft is slightly bent, although I doubt it.

I’m just freely spinning the saddle with my hand. If the ring gear spins with the saddle, I.e the worm gear is removed, everything spins freely. If I replace the worm gear, and have the clutch loose, the ring gear can not spin anymore bc it is engaged with the worm. How’re when I try to spin the saddle freely it sticks in a couple spots. ?So that is why I suspect the clutch

hopefully that makes it more clear. ?I noticed it was sticky trying to balance my telescope and I have been messing with it trying to figure it out. I don’t think it’s the bears as it spins nice when the worm is out.?

the other thing I note is if the clutch knob is really loose, it is almost like the RA shaft wants to unscrew itself out of the. Oh that’s, like the bottom threads are engages in the bearing. Maybe it has something to do with it?

mike

Hi Mike,

When you cleaned the worm did you actually disassemble the aluminum clutch discs with the translucent plastic clutch disc sandwiched in between? The plastic clutch discs and both aluminum clutch discs must be totally free of grease or you get sticky movement even with the clutch knobs loose AND you cannot get the clutches to lock well no matter how tight you make them.?

Other problems I've seen on people's mounts are the aluminum clutch disc on the axles are not perpendicular to the axles which causes a slip, grab slip grab with the clutch knobs free. The ever popular damaged or contaminated bearings, the slightest dirt can cause havoc, misaligned or not fully seated bearing caps and bent axles.?

I would suggest inspecting the bearing caps to see that they are seated, you can check them by using a feeler gauge and confirming that the gap between the main mount body and the bearing caps is perfectly even all around the mount. If not you will need to reseat them to square the bearings on the axle.?

You can verify the axle is not wobbly by using a couple V-blocks and a dial indicator. Support the axle on the ends and place the indicator in the center, zero and rotate the axle. Swap the indicator with one of the V-blocks and check again, if it is out of true this is one issue you can check off. There may be more than one problem and in my experience it pays to check all potential issues before reassembly.

Just a few more things that are easy and quick to check out.?

Keep us posted.?
--

Chip Louie Chief Daydreamer Imagination Hardware?

? ?Astropheric Weather Forecast - South Pasadena, CA?

Hi Chip,
I think everyone here was right, looks like it just needed a very, very thorough cleaning. I got both axis cleaned up and applied some super lube. After getting the axis re-assembled, they move smoothly. I then put my 10" schmidt cass (LX200, about 40 lbs with the moonlight focuser) and about 50 lbs of counterweights on and I was able to balance it pretty well. So that is one thing solved. Axis both moved very smoothly after all the cleaning.?

Next thing to deal with is I could feel some roughness in the RA worm bearings, so I will order some high precision versions on those, and the worm block closest to the motor on the dec axis is very tight, was impossible to remove without some tapping, and will barely rotate in its place. I'll lightly sand the post on it and see if i can't get it to fit better - it will be hard to adjust the worms without the block rotating freely.

Mike

Hi Mike,

Well that's good to hear, it is usually just old dried up dirty grease that messes up the works. But once you have SuperLubed you just have to worry about contamination as it will never gum up on you.??

Did you get some dirt or maybe corrosion in the little post hole that goes through the top plate to make it tight? I would not sand it without knowing the cause as if you get spring loaded worms in the future you don't want that hole to be oversized. McMaster Carr has ABEC-7 bearings for $8, this is relatively cheap for reliable supplier.?

--

Chip Louie Chief Daydreamer Imagination Hardware?

? ?Astropheric Weather Forecast - South Pasadena, CA?

I’ll check for dirt. I could feel a turned edge at the bottom, I wonder if it got dropped or something. Can feel a fine turned up edge at the bottom of the pin.?

was just planning on sanding that peg on the worm bloc itself, ?it sure I will be able to do one piece blocks. I am using an Onstep Goto system I built, might have to make my own one piece worms so I can mount my steppers. If the existing one piece worms still had the mounting holes similar to the ones on the side of the mount I could 3D print myself and adapter pretty easily

Mike