The Jig Is Up: Five Items Besides a Jig You Need to Bend a Metal Tube at Home
If you're trying to bend an aluminium tube to make a piece of furniture or for any other type of project, you need a jig along with a few other items. With the right parts, you can create a range of acute angles, even with relatively thick tubing. Here's what you need:
1. Soap and blow torch
So that you can bend the tubing using induction, you need to heat it up. This is called annealing the tube. To do this, use a blowtorch. To measure how hot the torch is getting the metal, mark the metal with a few lines from a bar of soap. When the soap turns black, the tube is ready to start bending.
2. Vice
A vice prevents your jig from slipping and sliding along your table, and it's essential if you want a quality bend. If your jig already has a clamp built into it, use the vice to boost the power of the clamp. Make sure that you have a steady work surface that is anchored to the ground, as otherwise your jig may move around regardless of whether or not you have clamped it in place with a vice.
3. Tube bending dies
Arguably, the most important elements when bending metal tubing at home or in an industrial facility are the tube bending dies. These two pieces consist of a straight edge and a semicircle. Essentially, your tube is going to sit between these elements, and the straight piece is going to hold your tubing steady as it moves along the curved piece which creates the bend in the tube.
You can buy these dies as a pipe bending kit along with the jig, or if you already have a jig designed for tube bending, you can outfit it with new dies. You need a die that is designed to hold a tube of the diametre you plan to bend and that has the curve or angle you desire.
4. Internal bullet
An internal bullet is a piece of metal, shaped like a bullet that you can insert into your tube before you bend it. If you don't use a bullet, you can bend the tubing, but the metal is likely to get warped. Conversely, by inserting the bullet, you help protect the integrity of the tube's centre and prevent the tube from getting smashed together by the dies.
5. Long ratchet
Once you have the tube securely placed between the dies with the bullet inside of it, you need to start turning the jig. If you are trying to bend a relatively large tube, you need all the leverage you can get, and that means using a long ratchet. A short ratchet will take much more physical strength, and it won't be translated to the jig as much as if you used a long ratchet with less physical output.
