Reposting due to mess

The newsgroup was under attack by an idiot. It looked like a "hipcrime" attack. The attack seems to have been shut down.

I saw your question -- and some valid answers -- yesterday. I did not answer because I did not have good advice to contribute.

Sounds like making modular tent poles.

I don't know enough to be sure of doing this properly, so I'll let you dig back for the other answers -- or hope that they are reposted.

Good Luck, DoN.

You can use the term 'swedging' to mean either expanding or reducing the ends of the tube.

There are 3 processes usually used to do this

-ram die: clamp tube, use a ram to expand or reduce the tube

-hydraulic expansion/reduction: a ram pushes a cone shaped mandrel into a matching set of fingers to expand an almost round shape. (works the same to compress things)

-rotary pounding machine: rotary hammers pound the tube down, works well for tough materials.

A shop with a suitable expansion machine can do do several hundred pieces per hour using generic tooling. Expect to see a setup charge and then perhaps $.15 to $.20 per end if you can find a good supplier.

You can make your own ram dies with a suitable clamp mechanism and the double acting ram. The ram die needs to be hardened and polished. The clamp needs to be hardened and seratated. It will be hard to get to the same pieces per hour that a good expansion machine can do but the equipment cost is much lower.

Wayne Lundberg wrote: