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whoyakidding whoyakidding is offline
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Default Tube cutting on lathe

On Thu, 10 May 2012 01:17:54 -0400, "Existential Angst"
wrote:

"whoyakidding" wrote in message
.. .
On Wed, 9 May 2012 20:03:45 -0400, "Existential Angst"
wrote:


Or, an abrasive wheel on a RAS/chop saw, using a stop. Quick too.


I'd use a dry cut saw with a stop. With care you wouldn't even have to
tighten the vise although some sort of lever or wedge used as a quick
clamp might be nice. Maybe 5 seconds per cut. Hardly any burr but
maybe another 10 seconds per end against a wire wheel in a bench
grinder to knock the sharp corners off. I can't believe that anyone
would even consider using a lathe to make or deburr cuts like that.
Kids these days.


I wouldn't even bother with a vise.


A dry cut saw would be slick but my main concern with holding the tube
is as the long piece gets shorter and lighter it needs to be held
tight enough that it can't shift a little and rip teeth off the blade.
A sleeve clamped in the vise maybe? The other thing I've found with
using any kind of chop saw and using muscle to hold the material is
that with lots of cuts and an old fart operator there's some risk of
repetitive motion injury. A year ago I was using a miter saw on and
off all day for about 3 weeks. I didn't realize how much muscle I was
using to hold the material down. It gave me golfers elbow and it's
still not fully healed. It made me more aware and I'd be especially
careful If I was paying somebody to do a similar job. It was
definitelyl painful and debilitating. I just grin and bear it but an
employee could turn an injury like that into a string of doctors
appointments or worse. Since we're only talking 200' at a time I guess
it's not an issue here though.

With any length of tube and a tube stand, just hold the tube by hand while
you feed in the RAS with an abrasive wheel, or on the chop saw. The tube,
with 049 wall, won't distort at all, with an abrasive wheel.


I agree there'd be no need for clamping with an abrasive saw. But for
clean thin walled material the dry cut is way nicer and faster. Hardly
any sparks or burr or heat.

Mebbe just a cupla seconds with a deburring tool, some emory or scotchbrite.


A wire wheel on a bench grinder is perfect for this job. I'd make a
pin type holder for the short pieces.

I cut 1.25 solid round, 2" sq tube (1/8 wall) all the time on a RAS, just
holding the stuff by hand.


Me too with abrasive. But it takes a bit more care with dry cut.

Yeah, I don't understand all this lathe stuff either, unless it was a cnc
with a barfeed.


He seems determined to make it as difficult as possible. Jobs like his
are typically set up in half an hour and carried out by the lowest guy
in the shop. This discussion is another example of things taking
longer to talk about than to do.