Pressure Turning on a Chinesium Lathe

A while back I watched a video by Joe Pieczynski on pressure turning. I
immediately thought, "Now that's something I'll never use."
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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.
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Reply to
Bob La Londe
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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
Reply to
etpm
Thanks for that. Like you, not sure if I'll ever use it but nice to know. I saw in the comments a recommendation for a live center with a built in spring. That way if the tail stock works loose some it won't fly away quite so quick :)
Reply to
Leon Fisk
Thanks for that. Like you, not sure if I'll ever use it but nice to know. I saw in the comments a recommendation for a live center with a built in spring. That way if the tail stock works loose some it won't fly away quite so quick :)
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That would be handy for tapping too.
Reply to
Bob La Londe
In case you run into any old machining books or old-timers like me, keep in mind that a "live center" is not a dead ball-bearing center. That's a dead ball-bearing center.
A live center is one that's under power -- like a center in the headstock.
The terminology has changed, but it's something to be aware off, because a lot of the reference material for amateur machinists, such as the old Colvin and Stanley books and the MAP books, uses the old terms.
Reply to
Ed Huntress
Wood turners use that and so do metal Spinning on wood lathes. Called Friction plate or various other Friction Chucks. Sometimes they are cup shaped. I've spun metal on a wood lathe and turned a plastic bowl blank - flat disk round - plexi - so I could heat it in an oven and press it while very hot down on six stout pegs and hold it there in a clamp as it cools. Makes a fluted bowl.
Old technology concept but is very low profile on metal lathes.
Martin
Reply to
Martin Eastburn

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