9A gear train question

[dbb-the-bruce]

So I searched and found this:

Gear train is 20/80/56 with 40 tooth on the outside of the lead screw end.

I observed the "extra" 40 tooth gear on the lead screw and thought, cool, that's to swap in for the 20 tooth stud gear if I want to cut really fast threads (4 TPI). Well not so much, the stud gear appears to be two gears machined out of the same hunk of metal although the books says it comes off (with an arbor press?) not really clear and probably not ment for quick swap out to the 40 tooth gear.

So what's with the 56 Tooth (installed) and the spare 40 tooth gear on my lead screw? I could swap them and threads would be 1.4 times "faster"

What's the 40 tooth gear for?
Thanks.

 

[RandyWilson]

You are correct in what the 40 tooth does. It is supposed to be a separate gear that replaces the 20 tooth for the coursest threads. Got a pic?

 

[dbb-the-bruce]

Ok, so I just don't get how the 20 tooth stud gear comes off the reversing tumbler. I've got the newer style with the spring loaded pin and the three holes in the casting for fwd/neutral/rev.

The nut comes off just fine but the gear seems to be pretty stuck on. I finally got it loose and now it's a lot easier to switch. The 20 tooth has probably been on it since it left the factory.



The flange on the second gear threw me off, looked like it might be all one piece.
Thanks.