Re: High worm torque
|
Hi gang, That is a good question and I'm surprised to find that reported -- on one system let alone 2 systems! I have not observed that on my GM8 or CG11 systems (yet). ? I think that is not supposed to be happening and you should call Losmandy to discuss it. ? The ring gear must ride on some bearing.? If that height is changing, the bearing is flexing and allowing the movement.? I thought that was nearly impossible (though every solid thing has elastic properties if forced strongly enough). ? ------------------------- I thought the system works like this -------------------------- The Ring Gear is the large flat gear with teeth all around its circumference.? That is driven by the worm gear. ?? ? I'll sketch it like this: ? ?? ? ? ? ? ?))))||||||((((? I will sketch the center of the ring gear teeth like this: ? ?))))||||||(((( ? ?<- center here ? ?? ?the Ring Gear is always driven by the worm, which I will sketch like this: o ?. For proper functioning, without jamming, the center of the worm gear must closely match the center of the worm gear axis. ? The worm gears in mounts like the Losmandy (or Orion Atlas/Synta EQ6) has a smaller diameter than what would be the diameter of the ring gear teeth.? So the worm gear, if represented by a circle ?o ?must have its center at the same center of the ring gear. ))))||||||(((( ?o ? <- ring gear and worm gear both centered here The plate on top which I sketch as this ?________?? holds the DEC axis, or the telescope: ________ ? ?telescope on top of that if DEC axis, ?or DEC axis assembly if this is the RA axis. ? ________ ? ?clutch plate on top is this line ___ ))))||||||(((( ?o ? <- ring gear and worm gear both centered here ? ? ?| ? ?| ? ? ? ? ?? ? ? ?| ? ?| ? ? ? ? ? ?this rod represents either the counterweight rod axis or the RA polar scope axis ? ? ?| ? ?| If your ring gear is able to move vertically when you tighten your Clutch knob, then the ring gear center will be shifting with regards to the worm gear.? This is not supposed to happen. ? In the Orion Atlas, the ring gear sits on a large roller bearing, designed for automobile axles.? In the Losmandy systems, I am not sure what that sits on.? It is likely a flat needle bearing. ? In the Orion Atlas, you can adjust the ring gear height using plastic shims.? You do that until the ring gear center is very close or exactly on the center of the worm axis. ? On the Losmandy systems, there is no adjustment provided that I know of. ? You have essentially no adjustment possible on the height of the worm gear because that height is machined into the Worm Bearing blocks that hold the worm. ? You can only adjust the worm gear to ring gear tooth spacing (horizontally in my sketch). ?? So I'd call Losmandy and report this problem. ------------------------------ There was a report on-line from Michael Siniscalchi, who found his ring gear plate got distorted, so he needed to file it down flat.? I wondered if his system somehow got far overtightened by the clutch knob and somehow distorted the plates.? Here is the website: Possible solution? You should not need to really torque down hard on the Clutch knobs to get the clutch disk to hold the upper axis.? If that is slipping, and you need to really overtighten the clutch knob, you could be distorting the ring gear surface with too much force down the axis (vertical in my sketch). ? These clutches slip from lubricant that diffuses on to their surfaces (from the internal lubricated bearings) and these need to be cleaned with oil solvent, or.... I do have some high friction clutch disks which resist oils and moisture. ? I have these in sizes for the GM8, G11, and CG11, that reduce the clutch force needed to get a strong grip between the ring gear surface and the upper axis (telescope or DEC axis). ? If you want to try them and see if they eliminate the problem, let me know. Best, Michael ?? On Fri, Sep 22, 2017 at 4:22 PM, Paul Homer phomer60@... [Losmandy_users] <Losmandy_users@...> wrote:
--
|
Michael Herman