Re: Reducing DEC Backlash with Titan 50
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Aubrey,
It's the RA that this matters most on a Titan RA drive.? Variable friction causes the drive speed to slow then speed up...it's either periodic or non periodic error.? Either way you want it to be near zero friction.? That's what the bearings are for.? But the worm has the ring gear and no bearings at that interface...just friction.? So that needs the best lube and that's the question.??
You also want near zero backlash else you get autoguiding time lags and hysteresis that PHD2 does not like.? So that's the other end of the coin....no friction but no autoguiding!??
Between those two extremes is the optimization point.? Springs can help if they keep the surfaces in contact but not too tightly.? Lubes are essential to minimize friction. Aligning bearings to keep balls from pinching (the Titan has these bearings in a massive cylindrical sleeve...they can't go off axis...the OVision worm did this for the G11 and they used a Belleville R4 spring washer for the end bearing).
Have fun,...get some nice images!
Michael
Thank you. I have always just tightened my endcap down and did not notice it. I will check it out when it gets it¡¯s annual oil change. ? Thanks ? Aubrey ? Sent from for Windows 10 ? ? it¡¯s a spring washer rather than a spring, and is housed inside the worm block assembly.
Regards,
? -Paul
On Sat, May 8, 2021 at 12:47 PM, Aubrey Brickhouse wrote:
Can I ask a question on this subject. I have a fairly new Titan and I have never seen a spring in the assembly. I have relubed it several times but have never taken out the worm and so I can not say if mine has one or not. ? Thanks ? Aubrey Brickhouse ? Sent from for Windows 10 ? ? Dan, yes, indeed. I have a Titan50 and a G11 :)
The spring loaded adjustment I'm talking about is not for the whole worm block -- it's at the end of the worm block, on the opposite side of the gearbox. It pushes a spring-loaded bearing into the worm block, preventing it from moving horizontally, side-to-side. It may look like this, below, or have a single slot that you can use a screw-driver or a quarter to turn. If it's not pushed in far enough, the worm will float left to right:
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Regards,
? ?-Paul
On Sat, May 8, 2021 at 10:27 AM, <dkfcpalfd@...> wrote: Paul:
Thanks for responding.? Do you have a Titan?? Losmandy has been telling me that they came out with spring-loaded worms for the G11, but not the Titan.? When I first heard about the spring-loaded worms for the G11, I initially was told that feature was in development for the Titan.? Then, several months later, that went away, and I have been hearing from them that spring-loaded worms may never happen for Titan.
Right now, I'm going to try adjusting up the TVC on the HC.... the Gemini-2 website says that is a built-in DEC backlash compensation adjustment that is available.
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Michael Herman