Tumbler gear replacement questions

cdhknives

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I bought 3 new gears from Clausing about a month ago and was installing them today. Some questions/issues are below. Maybe I'm paranoid...but the perfectionist gene is pretty strong in my family! Thanks in advance!

Both tumbler gears (20 and 24 tooth) and the spindle gear they mesh with were replaced:

1) The inner bushing/sleeve (forget the correct term) was a very tight fit into the new gears. Is it normal that I had to press them in with a vise? It wasn't particularly hard, but way too much for hand fit. They basically fell out of the old gears. I did not deburr anything and though after the fact that maybe the new gears had a bit of flashing...too late to check now.

2) The only adjustment for gear mesh is the plate the tumber lock pin goes into, right? I move it all the way up and still have this much slop in the gears. Is there a better solution?

uABUXc7.jpg
ahF2d0d.jpg

2A) When set all the way up like that, the 24T gear is barely touching the spindle gear. I can go past the standard detent hole and get this much mesh but the tumbler pin is in the top of the plate's slot:

2nudb5O.jpg
nna98qz.jpg

3) The wear pattern on the new spindle gear looks poor to me. Will this 'wear in' or is there another adjustment I need to use to get better gear to gear contact alignment? This was not under load, basically just running to check fit and function...

I7JuWrH.jpg
 
I agree that the lack of full meshing of the gear in the top photo is reason for concern(the one below the big gear).
It's hard to tell from a photo but maybe the gear could be moved up by using some sort of eccentric bushing. The
wear pattern is not a big concern as they will wear in over time. A press fit on the gear bushing makes sense to me.
If the gear in question gets moved into place, maybe something could be adjusted to get it to move a bit more up.
You mention a standard detent hole, maybe that could be repositioned for better fit of the gear.
 
You don't want the bushing turning in the gear. So the bushing should be a light press fit in the gear.

How much radial clearance is there between the new gears and the shoulder bolts that they run on? I would have replaced them, too.

How much vertical movement is there between the tumbler and the 10-1547 Stud? Try rotating it 180 deg as most of the wear will be on the top.
 
The inner bushing has anti-rotation ears. It does not need a press fit to prevent rotation. They have no real slop on the studs/shoulder bolts.
 
You mention a standard detent hole, maybe that could be repositioned for better fit of the gear.

This has already been done. Moving it all the way ended up with what you see in the pics, and left the reverse direction literally not meshing in the standard position. Running the tumbler down to the stops allows good meshing but there is no standard detent in that position, only the top of the adjustment slot.
 
This has already been done. Moving it all the way ended up with what you see in the pics, and left the reverse direction literally not meshing in the standard position. Running the tumbler down to the stops allows good meshing but there is no standard detent in that position, only the top of the adjustment slot.

Maybe look at the geometry of the parts and see what can be altered to move the gear where you want it. If that's an idler gear,
you could put in a gear with several more teeth...
 
I've found that if relatively dry the bushings can be a hard fit. A couple drops of 30 wt oil and they go together fine.
 
It appears that the 2 tumbler gears are different size . Shouldn’t they be the same size so when you reverse them the gear ratios remain the same
 
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They are idlers, they just change directions. No effect on ratios.
 
In the first pic the 20 drives the 24 then the 24 drives the rest of the gear train and in the fourth pic the 20 drives nothing and the 24 is driven by the spindle and drives the rest of the gear train in the opposite direction so in my head the elimination of the 20 definitely changes the ratio as well as direction of the rest of the gear train but I’m not fully coffeed up yet.
 
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