According to Dev Null :
"Doug" wrote in
:

Dev Null sezz:
I have a widget that has some tubes coming out. Tubes are hard
copper ~1/2-inch O.D. actual. I want to attach plastic tubing
to the copper tubes. I would like to create beads in the
copper tube. Copper tube can not be removed from widget.

Can anyone suggest a method to create a bead or an
alternative?

If you are putting a bead on it to use as a roadblock for a
clamp or similar - why not just flare the end of the tubing?

[ ... ]

I think this will make it difficult to install the plastic tubing.

Hmm ... what about a double-wall flare set taken only part way.
IIRC, you start out with a cylinder, clamp it in the bar and compress a
die to the end resulting in a shape like this (view with a fixed pitch
font like Courier to avoid distortion of the drawing, though I *think*
that this one should be pretty immune):

_______/\

-------\/

and the second stage (which you skip) folds that in like this:

________//

--------\\

Try it on some spare 1/2" copper tube to make sure that what it produces
is what you need before doing it where it matters.

You might even be able to reduce the size of the bulge by
clamping it a bit shorter than it is supposed to be.

Good Luck,
DoN.
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