On Nov 28, 2:01 pm, Bill Schwab wrote:
John Martin wrote:
On Nov 28, 2:20 am, Bill Schwab wrote:
Hello all,

I am using 2 inch square Al tubing (0.125 thickness) as part of a frame
for an experimental fixture. Part of me wants to flycut it to remove
some dings, and part of me wants to leave well enough alone. Knowing
that I can always start over if the tubes (11 in long each) were to warp
like mad, I might just try it.

What is your best guess? Would knocking the skin off of the tubing
cause it to warp or twist a lot? Is there something else you would do
to make a presentable finish? It is not terribly important. I can
probably get to a sandblaster, though it is not as accessible as in the
good old days. Something I can do in the comfort of my garage gets
extra points.

Thanks,

Bill

Try it. Or not. It's your choice.

How in the hell would you expect anyone to be able to give you a good
answer, without knowing the depth of cut necessary and the finish that
you want?

John Martin

Well, I have developed considerable respect for the frequent
contributors here. You might care to read some of their replies,
because they are insightful, based in experience and professionalism.

Ironically, one of them even suggested a depth of cut, of the same order
of magnitude that I had in mind.

Bill- Hide quoted text -

- Show quoted text -

OK, Bill, I'll try it again.

I, too, have a good deal of respect for most of the contributors
here. You got some good information on finishes for aluminum, but no
one fully answered your questions, did they?

One person "even suggested a depth of cut, of the same order of
magnitude that I had in mind." What an amazing coincidence. I'd have
suggested a depth of cut of .0000", because to me those dings don't
look any deeper than that. From here in Maine, though, it's a bit
hard to see your workpieces. You go on to say that the cut of .010"
will not get off all the dings and gouges. Well, what will it take - .
030", .050", .075", more? If you'd simply stated the depth of cut
necessary to clean up your workpieces, someone could have readily
advised you whether you were likely to get any significant warping.

Same criticism of your "presentable" finish. To some, it might mean a
mirror polish. To others, a smooth but dull finish. Or a rougher
brushed, machined or shotblasted surface. I'm not a mindreader, and I
don't know of any in the group. I could be wrong, though.

John Martin