I recently spent too much time making a pretty poor twist wrench that only fit 2 sizes of stock. So I decided to make an adjustable twist wrench. It works a treat.
Here's how to do it:
Step 1: Tools and Materials
Angle grinder or hacksaw
Iron bar. The size isn't too important, just so long as it looks and feels more or less right. I went for 10mm.
Step 2: Cut!
Figure out where you want your bar to join your wrench. Remember the aim is to have a reasonably straight line so that you get an equal twist.
Mark the wrench with a sharpie.
Cut a section out of the wrench and test that your bar fits.
Step 3: Weld!
Securely clamp your pieces.