On 5/10/2012 10:48 AM, Existential Angst wrote:
wrote in message
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On Thu, 10 May 2012 01:17:54 -0400, "Existential Angst"
wrote:
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.
What are you calling "dry cut"? Carbide saw blade??
I'm assuming the OP's tube is steel, since 049 is not a std alum wall.
If it WAS alum, I'd say 80 tooth 10" carbide blade.
Since it is apparently steel, I'd say abrasive. Unless dry cut is totally
different.
They do make a steel cutting circular saw blade, which I've never used, just
read about.
They seem to work well, but iirc, they aren't cheap -- or at HD.
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.
The only thing I'd use the lathe for is facing, and only if that level of
finish/accuracy were req'd.
Then, while on the lathe, I"d deburr it. But only if the lathe were
necessary.
Have you noticed that we are being completely ignored by the OP?? LOL!!!!!
Nope, I'm weighing all these good ideas! When we cut pieces in a
horizontal bandsaw it goes pretty fast but the pieces of tube are 2.375"
or 3.375" in qtys. of 24 to 48. We cut them 1/16" long in order to get
the ends square and the length in spec. The deburring op is a little
more, the inner and outer really get a slight chamfer. The tube gets
swaged later on both ends and the chamfer helps the steel flow rather
than fold up. So, I think if I can cut to exact length in the first op
and only have to chamfer the ID, it would save two operations. I'll try
our abrasive saw to see if it will cut square enough. I don't have a
dry cut saw.
Here's the finished product"
http://www.wisesales.com/catalog/pro...46/image/1877/
The tube becomes the arbor hole by being press into a stack of wheel
brushes and rubber spacers using a 50 ton hydraulic press. Any
resistance from a burr or any other defect and the tube becomes an
accordion and is very difficult to recover the parts.
Most of the orders are for 4" and the company that cuts those for us
does a good job...the should, they charge $0.50 each! The orders for 2'
and 3" are very few by comparison but are a pain and we have to have a
skilled person do the job.
Thanks for the advice!