[Shop-talk] bending c channel, what are the miter angles?

[Karl Vacek]

As already answered the angles are 45 degrees off each leg for a 90 degree
included angle.  However...

The other consideration is the bend allowance for the sheet metal - the
thickness of the web.  If you just cut a square notch in each leg you'll end
up having to really stretch the metal of the web on the outside of the bend
to make the full 90 degrees.  Try this: http://sheetmetal.me/bend-allowance/
or Google "sheet metal bend allowance" for lots more info.

Karl

-----Original Message-----
From: eric at megageek.com
Subject: [Shop-talk] bending c channel, what are the miter angles?

I have a 6" c channel piece of steel that needs to be bent at 90 degrees on
both ends.  So, I need to cut the 'sides' (Leg) of the channel to allow the
bend and then to weld the mitered sides back together.  (this is really
simple, but I can't explain it well.)
Think of just folding a c channel into a 90 degree.   I need to cut the 
sides to allow the bend and be able to reweld it.
I need to know how to calculate the angles to make the cut.