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How to bend copper bars and copper pipes

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Copper bars can be bent with virtually every bending process.

While copper is soft, it’s not soft enough to bend smoothly and perfectly on its own. Bending copper pipes without special methods or tools usually results in pipe collapse. Instead of a continuous curve, the pipe will crimp and fold at the intended bend point. For crafting, it’s generally not the look you want. For plumbing, it impedes water flow.

3 ways to bend the copper bar

There are 3 ways to bend the copper bar to fabricate your products.

  1. Large-radius bent copper bar is rolled on a section bending machine(also known as a profile bending machine or angle roller).
  2. Curved copper bar requiring tight radii is rolled on a rotary-draw bending machine through a technique called mandrel bending.
  3. Helical spiral bending can be performed on any copper bar section using a CNC 4 roll bending machine.
bending copper bar

For very tight radius bending you can utilize a stretch forming process where you must stretch the material (draw the material) around a bend die matching the desired bend radius.

But for larger or sweeping radii must utilize a roll bending process (section bending). At this time, need to use a flat copper bar bending machine.

Flat copper bars are solid, which means that they can be easily bent into the shapes required by a project. There are two ways to bend non-circular or non-square copper bars:

bending copper bar
bending copper bar

The easy-way and hard-way to bend copper flat bars

bend flat bar
bending flat bar

Easy Way

The Easy Way: This involves bending a bar along the wider axis of the bar. This means an easier bend, reducing the problem of rippling on the inside of the curve. Bars bent the easy way resemble a belt when completed.

Hard Way

The Hard Way: Bars bent in this manner are bent along the thicker axis. This also presents more difficulty during the bending process, as rippling and compression can occur on the inside of the bends. When bent the hard way, bars resemble a metal washer.

Two Types of Copper Bar Bending Machines

How to bend the copper pipe and tubing

Because of its exceptional formability, copper can be formed as desired at the job site. The copper tube, properly bent, will not collapse on the outside of the bend and will not buckle on the inside of the bend. Tests demonstrate that the bursting strength of a bent copper tube can actually be greater than it was before bending.

There are a number of reliable ways to bend copper pipe. Because copper is readily formed, expansion loops and other bends necessary in an assembly are quickly and simply made if the proper method and equipment are used. Simple hand tools employing mandrels dies, forms and fillers, or power-operated bending machines can be used. A few of the methods don’t even require special tools.

3 Tips For Bending Copper Pipe

  • Pipe Support: Supporting the copper pipe along the entire length of its bend is key to a consistent shape. Support can either be inside or outside of the pipe.
  • Bend Slowly: Bending the copper pipe quickly might still crimp it, even if it is properly supported. Or, if you do manage to get the right curve, ripples may develop on the inside of the curve. Always bend slowly.
  • Shape the Bend: Bending the pipe over a padded knee is the quickest way to bend copper pipe to an approximate 4- to the 8-inch radius. But you can also use other curved shaping items: metal cans, buckets, or large pipes.

3 methods for bending the copper pipes

  1. Spring to Bend the Pipe: Tube-bending springs fit in the copper pipe and act as support to better distribute the force. Bends as extreme as 180 degrees are possible with tube springs. Tube springs come in kits of various sizes that fit copper pipes ranging from 1/4-inch to 5/8-inch in diameter.
  2. Sand or Salt to Bend the Pipe: Dense materials packed inside the copper pipe produce an effect much like pipe bending springs. They prevent any single area from receiving all of the bending force. Instead, the force is distributed along the entire length of the curve. Fine sand and salt can be used.
  3. Pipe Bending Tool: A pipe bender is a small, inexpensive, dedicated tool that does only one thing but does it very well. It bends various sizes of copper and other soft metal pipes to a set radius, usually about 2 or 3 inches.