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Default Copper Tubing too big, how to size?

On Jan 17, 6:43*pm, "RogerN" wrote:

I measured the tubing and reads around .655", about .030" too big. *I was
able to taper the end of the copper and hammer the compression nut onto the
tubing, this "sized" the tubing enough to get the compression sleeve on and
I got the valve on the line, but I would like to fix it better later.


I'd be worried about anything that needs to hold water pressure. But
packed away in my instrument repair tools are a set of draw rings,
with polished, radiused edges that shrink annealed tubing (usually
brass, but copper should work) if you encourage it through with a
rubber mallet from the other end (usually you only anneal the part you
are going to shrink). The smallest one wasn't quite small enough for
my purposed so I made a "number 0" on the lathe. I kept a can of
crisco with them.

Often a tubing cutter will swage the edge near the cut somewhat.

For expanding, I had a segmented expander, but turning a taper on a
piece of junk steel and then filing three rounded flats on it worked
pretty well. A closed pair of needle nose pliers works sometimes too
(or maybe with a shim stuck in the jaws to change the angle). These
of course make a belled end - the expander could make a parallel sided
section as you could move the bulge in and out instead of only at the
end.)

The difference in behavior between the annealed and work hardened
condition is substantial.