RF-45 clone fine feed reassembly trouble
#1
Hi all,

I have just done the common gearbox rebuild on my RF-45 clone, changing the gear shaft bearings, oil seals, etc. I did not change the spindle bearings.

I am having trouble getting the quill fine feed mechanism to work. The rack mechanism works ok.

It used to work before, albeit with a tight spot.

It seems to me the large worm wheel that engages with the fine feed worm only meshes properly and works smoothly when it is in a very specific position. The worm wheel no longer ends up in this position when I put it back together now - it gets pushed in too far to the left and binds solid. I have looked at every variation of the manual I can find and none of them show any parts I don't have - the only variation is in the washer and screw parts that hold the return spring on which I do not think is relevant.

In desperation I made some spacers to go between the shoulder on the pinion shaft and the worm wheel - I've ended up with 8mm and could perhaps use another 1mm, but it works ok.

The mechanism also seems to get a bit tighter as the screw holding the return spring cover to the pinion shaft tightens up while the pinion shaft rotates. I guess this screw has always rotated with the shaft and I just never noticed. It's pretty loose at the moment which is why it tightens a bit. If I tighten this screw right up it clamps the whole quill lowering mechanism, both fine feed and using the handles like a drill.

So it feels like the pinion shaft is being pulled way too far to the left, but the return spring hooking onto the screw on the left hand side doesn't give a lot of room to move.

I'd love to know what I've messed up. Has anyone else experienced problems when putting the fine feed back together?

Regards, David.
Reply
Thanks given by:




Users browsing this thread: 1 Guest(s)