Sloppy focus tube Celestron 114LCM (mostly ) eliminated

[Ro3bert]

Convinced I would be able to remove the slop in the focuser I decided to remove the assembly. 

Below is the assembly before removal from the scope.

Focuser after removal

As it turned out to get one nut holding the focus assembly I had to remove the mirror assy because I could not reach the nut from the spider (my hand was too large to get through).

The focus parts after disassembly.

All parts were cleaned, metal with acetone and plastic with dishwashing detergent.

Notice to the left of the rack slot a slight indentation (marked with two lines).

I used sheet polystyrene for filler strips. You can see the first one in place in the next image.

I used .015" (4mm) sheets cut into narrow strips for three indentations.

The styrene sheets were lightly coated with white lithium grease as were the pinion and rack.

After assembly the adjustment was a bit tight so had to adjust the screws that hold the pinion shaft in place.

After the scope was re-assembled I re-collimated.

There is no movement along the rack at any place when the focus tube is all the way out, but there is still a bit from side to side (though not nearly as much as originally).

It seems I will still have to add two more thin strips of the thinnest sheet I have to remove the last bit of slop, but that comes later.

[Alan64]

...well done, Robert.