How to bend rebar

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When you prepare rebar for concrete reinforcement, it seems to be important to have a bend on the corners (as opposed to the end of a bar). To make this project modular, we designed rebar assemblies that can be built ahead of time and slipped into place once the forms are placed. This does require some bending and welding with fairly close tolerances, since we want the rebar to sit only about 3" from the edges of the slab. Thanks to Jershonda, we have this guide on how we made that happen.

Gather supplies and tools

  • 1/2" rebar stock
  • Securely attached bench vise.
  • long 1/2" (or greater) metal pipe
  • measuring tape
  • marker
  • spec. sheet

Steps to do

  1. Measure and mark the rebar at the desired length and at 2” less than the desired length.
  2. Set the rebar in your vise with the mark for the shorter length at the edge of the vise jaws.
  3. Set the end of your leverage pipe at the mark for the desired length.
  4. Exert pressure on the lever to bend the rebar. Keep the pressure on until you get to an angle of about 120⁰ to 130⁰. This is 30⁰ to 40⁰ beyond the desired 90⁰ bend, but the metal will spring back very close to the 90⁰ you are looking for.
  5. With the #4 (½”) rebar we are using, a 2” radius bend loses about ½” of length. However, the diameter of the rebar compensates for that, giving the desired dimension fairly precisely.