View Full Version : General Metalworking Squashing a Aluminum pipe?

Matthew N. Masail
10-20-2013, 7:51 AM
Hi Guys, I post mainly in the Neadrethal woodworking forum, however I thought this question would be far more appropriate for your expertise.

I'm making a Banding Iron for guitar making, and went out to buy a pipe. I was hoping for something with a 1\8 inch wall thickness but the closest I could find was a

3 1\2 inch Diameter 6061Aluminuim pipe with 1\4 wall thickness. it was cheap enough so I decided to give it a shot.

The original plan was to go over it with a car to make it oval or (hopefully) tear-drop (ish) shape. but with 1\4 wall thickness I was thinking this may not be a good idea? as the walls might crack? or it might be too strong to do this with?

the other way I imagine is to cut along the length and then bent it into a tear drop shape, but then how to weld\braze the bond?
I have to bond the aluminum plate in the picture to seal the top side anyway, but I have no metal working skills and the bond must hold up to 250 degrees Celsius. is this something the can be trusted to an non professional metal shop? I'm in Israel, and the guys at the metal supply didn't know of any shop that they could recommend for aluminum work. any DIY way to accomplish this?

Thank so much !

Dennis Ford
10-20-2013, 2:23 PM
I like your idea of cutting one side and bending into a tear drop shape, it would need to be welded together afterwards. I would try to cut it along the manufacturing seam (if one exists). Bonding one end to the plate will also require welding to meet your temperature requirements. Not every metal shop can weld aluminum but ones that can are common here. Getting the welding done will likely cost more than the material but should not be too bad.

Leigh Betsch
10-20-2013, 3:05 PM
I have no idea what a banding iron is. But I'd squeeze it in a vise. It would be pretty crude, I have no idea if it would be good enough for you use, but I think it would be better than running over it with your car.

ray hampton
10-20-2013, 3:38 PM
running over it with your car could cut your tire but placing a steel plate between the pipe and the tire will help, another way would be to place a jack on the pipe while jacking your car up , you can stop when you get the correct bend /if you get the bend correct

Bruce Boone
10-20-2013, 7:00 PM
I don't know the application either, but you would do much better to get a stainless drain pipe from a sink and squash that in a vise. The wall will be less thick, but will be a much stronger piece and will be an exact ellipse. I made a laser reflecting tube by this method once and it was mirror finish and the perfect shape. A thick aluminum tube will definitely fail where it's squashed.

Matthew N. Masail
10-21-2013, 10:32 AM
Hi Guy's, Thanks for the responses! I think I'll try to find a shop that can weld and then cut and bend it. I hope that will work.

A bending iron is a pipe with a heating element in it (traditionally burning coal or something). it's used to bend the thin wood for the side walls of musical instruments. the reason for a tear-drop shape is to give a variety of radii to work with.

Brian W Smith
11-02-2013, 6:10 AM
Little late but?

Try an exhaust shop.....some place that has benders/swagers.They should have some SS exhaust tubing and can make quick work of flattening/heating/bending.They do this here(U.S.)on such a regular basis that it just isn't any big deal $$ wise.

raul segura
11-08-2013, 11:27 PM

raul segura
11-08-2013, 11:32 PM
harbor freight has aluminum weld rods/more like soldering but very tough (use a plumbers torch) . Id look at u-tube vids to get the idea of application. Other wise Id get SS steel muffler pipe and bang one out and use a torch for heating the iron.