On Wed, 18 Oct 2017 19:52:26 -0700, "Bob La Londe"
wrote:

A while back I watched a video by Joe Pieczynski on pressure turning. I
immediately thought, "Now that's something I'll never use."

https://www.youtube.com/watch?v=0DrI5B4hui0

Yesterday I bought some great price carbide blades for my 12" radial arm
saw. They didn't fit. No big deal. I have a lathe or three. I'll just turn
one of the arbors to fit. The little lathe is still all apart for the
duration. The middle weight is pretty much dedicated to small rod stock
collet operations so I walked over to the 1 ton 1440 and grimaced. I could
have used a couple parallels behind the stock, and shimmed it on the 3 jaw,
or I could have swapped out for the 4 jaw and dial it in, but what a pain.

Instead I used a live center to get concentric, and pressure turned it up
against the front of the jaws of the 3 jaw. I wasn't sure if my Chinesium
lathe would be up to the task, but it turned out to be dead easy.

Here it is. https://youtu.be/yMwaUokwDaY
Years ago I used to do a repeat job where I had to make a bunch of
1/4" thick aluminum discs approximately 6 inches in diameter. So I
would cut 6 inch wide flat bar into 6 inch lengths, saw off the
corners, and pressure turn them using an 18 inch swing lathe. I would
stack up 32 pieces, clamp them together with a bar clamp, and then use
the live center with a pusher disc to hold the stack against the jaws
of the chuck. I put a piece of paper between the jaws and the aluminum
for a little extra grip and to prevent galling if the stack stopped
spinning. After the stack was clamped I would remove the bar clamp and
tap the stack into (sorta) concentricity. I was a little scared the
first time I attempted the operation but I never had the stack come
out. Besides the fact that I saved a lot of time turning so many at
once the only burr was on the part next to the chuck. All the other
parts just had a sharp corner that was easily and quickly rounded
using a ScotchBrite wheel.
Eric