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Gear tooth question & the "Yugo" od surface grinders

And in response to zahn, space cutters aren't THAT bad for a job like this ! The reason they are not so perfect as involutes is they aren't involutes. They are made to another system called "composite" ...

You are correct, Sir. Admittedly, I even use them from time to time when the customer prefers it. But they rub me the wrong way, none the less. To be fair, I've always very freely admitted to being a GearSnob. And this is specifically, precisely the reason why. It is the very reason that caused me to take it upon myself ( as a much younger version of myself ) to get educated about the Involute Form and properly generated gears. The stark contrast of the smoothness and how gear pairs ( and trains ) FELT between the two just stuck in my craw and I've been prejudiced about them ever since. Plus, in my younger brain, the knowledge that one was "correct" and the other "an approximation" left no room for discussion. :) Though, even the hardest of stone yields to wear given enough years.
Joe -

That story about the drawing is the funniest thing I've read in ages. Thanks - as always - for the good story. Best wishes for you and your family having a Happy New Year.

I have a belt drive Boyar-Shultz 612 that I have taken
completely apart, and I think it is a smartly engineered
machine. Not at all a Yougo. I would call a Sanford a
Yougo, but not a Boyar Shultz. My machine had an oil
port on the front of the table. Right in the middle of
the tee slot for the table stops. I made a modification
to route the oil feed from the rear of the table. I used
an 1/8" drill bit soldered into a 3/8" extension rod.
I popped out the ball oiler 90° adapter elbow and drilled
the oil port out the back of the table. I tapped the hole
for 10-32 thread. This is a standard for small tubing
fittings. I was able to find a 90° banjo fitting to convert
from 10-32 thread to 1/8" push lock nylon tubing. The front
ball oiler elbow was replaced by a 64th size welch plug from
the auto parts store. With this feed line on the rear of the
table, I supported it with a rubber lined aircraft clamp and
ran the line to a Bijur lube pump.
I actually have 2 Bijur pumps. One for the table oil and one
for the column oil. I find red ATF allows the table to move
very freely, and I use Vactra #2 for the vertical column.
As for the rack gear, I bought a 16P and 14.5 PA gear from
McMaster Carr. I think it was a Martin gear.
McMaster Carr also has replacement bellows for the cross feed
screw. I remember them being $50 a piece or some high price.
But I bought them, because my grinder was nice otherwise.
I painted my Boyar-Shultz a deep red color, as I like how the
Van Norman grinders looked painted Red.