Steve W. wrote:

That part in hand is made of steel. 1020 or 8620? What kind of heat treat?

Easy enough to do a test on a piece of it and tell the composition. Or
use a steel currently used for a similar use.
Heat treat to current spec for a gear in similar use. No real need to
use the original factory spec if you know a better one.

Look at the books and you would know what the original specs should be.
Where are these books with specs for parts made 60+ years ago by
companies long out of business?

Depends on the item. However if it is a gear the simple solution is to
use published specifications of common gears of the time. The harder
spec would be to look at the back of the teeth and get the information
from there. In the event that the wear is bad enough to nullify that you
will likely be making a few others to match existing parts and bring the
machine into spec. in that case you simply need to use the original for
it's diameter and tooth count. Then cut a new gear for each worn position.


True for every job our company quotes. True for every part I've made in
my basement.

David

However your not making readily found parts in your basement are you? If
you are then why?

Most of what I make no one else does.

I look at it this way, just because I can go to the shelf and pick up a
1/4-20 X 1" cap screw, doesn't mean I shouldn't know how to make them.
I've visited countries where "automation" advances are made by
installing more people with files and grindstones! Ask them about CNC
machines and you get blank stares.

To get back to the original point, no company I've worked for would be
willing to spend $1-2K to get up and running a machine only worth $2k.
It's just not an effective use of resources. You get it running and
wait for the next aged part to fail. It's called being nickel & dimed
to death.

David