Tak drawtube wobble

[Lognic04 (Logan)]

Hi all,
I have tried to adjust my tak focuser, but I can't find the "sweet spot". If I make it feel nice to use, the drawtube wobbles an insane amount, but if I tighten the 2 Allen screws it is better but a lot of force is required to move it. And regardless of tension on pinion or glide, there is always a ~1cm movement of a laser collimator beam.
Hope you can help!

[Kunama]

Remove the complete focuser pinion assembly by undoing the round nut and the two screws under it.
Remove the focuser lock knob from above.
Then using your Allen key adjust the two setscrews that apply pressure to the glide strip evenly on both the front and back of the glide strip until the draw tube moves smoothly through its full length, but without any lateral movement. If the movement gets tighter at either end you have too much pressure at that end and the glide strip is not pressing evenly allowing lateral or up down movement.

Then reinstall the pinion and the brass carrier and snug down the two screws only until there is no backlash as you focus in/out, not too tight or it will become impossible to move smoothly.
Replace the cover plate and round nut....
Replace the draw tube lock knob on top and make sure the little brass disc is there.

When collimating the MT160 for imaging (or for visual use) extend the draw tube to the position where it would be if your camera is attached and focused. Then lock the draw tube using the knob on top before collimating.

[Lognic04 (Logan)]

Thanks. The focuser doesnt wobble up/down along the pinion axis but left to right 90 deg to the pinion/glide axis, so this is a problem. Also i cant lock it down in use due to an autofocuser - also wondering how id mount a 1/3 kilo stepper assembly to the single knob that locks the focuser down as lewis suggested? Surely that isnt strong enough to hold the whole stepper down with a really tight focuser (as it is now)

[LewisM]

You need to create a bracket as I actually said. You do NOT attach the motor mount to the 2 brass screws as Matt and I have explained it’s crucial to the pinion movement. Yes adjusting as Matt said will remove lateral wiggle.

You’ll need to attach the motor bracket to the focuser base flange screws.


No bloody araldite, OK?!

[Lognic04 (Logan)]

I have already adjusted in that way - resulting in a really stiff focuser movement

[LewisM]

Well back it off 1/16th of a turn until it lessens

[Lognic04 (Logan)]

Then the focuser starts wobbling...

[LewisM]

Then adjust the small grub screws on top after getting the pinion contact correct.

There is no way someone could adjust it for you seeing you are putting the auto-focuser on. Easy to do for visual use, but if you are auto-focussing, it's anyone's guess