<VV> Changing gear ratios in Corvair transmission

[Delta Mfg.]

----- Original Message ----- 
From: "Clark Hartzel" <chartzel at comcast.net>
Subject: <VV> Changing gear ratios in Corvair transmission


> Ken at Deltawerkes asked about this.  To change a gear ratio one gear
> has to be bigger or smaller and the mating gear has to be whatever pitch
> diameter fits the center distance.
***
ken sez:  We do keep the same pitch diameter/pitch circle as spec gears.
********
 You can't change a gear ratio by
> altering the number of teeth in the same pitch diameter.
********
Ken Sez::  Here is where the nasuea sets in ... we use the same pitch 
diameter blanks, but cut different number of gear teeth on that diameter. 
(g) .   Yes, we alter the number of teeth in the same pitch diameter.  Yes 
it works.   Don't feel bad... some very very intelligent people still tell 
me it won't work ... in fact, it is probably a testimony to your 
intelligence that you see it that way at first slice ... you would have to 
be stupid to think it would work.

If it helps, here is how they are generated:::  we use a vertical shaper; 
the cutter tool looks just like a true gear.   The workpiece blank is put 
under the sharp edged gear cutter, and both rotate while the cutter goes up 
and down .... it eats its way into the workpiece ...  shaves off a whole 
bunch of 0.001 wide chips .....   we select the change gears in the 
generator machine to generate the quantity of gear teeth we want for the 
ratio we want to achieve.... the resulting cut * HAS * to fit the ideal 
gear, because the cutter tool * IS * an ideal gear ( sharpened on one 
de.   )

This discussion is not by way of winning points in a geeky argument; just 
that it is interesting in what might be done ... probably a solution without 
a problem in Corvairs maybe ...  ( heh heh ) ... if you like please feel 
free to contact me off forum.... also, we show some of these on our web page 
(  www.deltainc-usa.com )   there are 3 low speed gears and 3 high speed 
gears ... these are driver gears; 3 each for the low speed and the high 
speed in our constant mesh autoshifted ground speed shifted transmissions. 
They run against normal classic spec gears.

Thanks for your time; ken campbell, deltawerkes.