RF-45 clone fine feed reassembly trouble

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RF-45 clone fine feed reassembly trouble

Post by dajt » Mon Jun 25, 2018 5:20 pm

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.

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

Regards, David.

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