So I'm looking for some U channel steel that doesn't have an inside radius corner. I want it to be square much like angle steel is. I'm building a bumper and want to be able to slide this onto my frame as the basis for the build. See the pick below if a diagram will help. The black box is the frame and the yellow is the type of channel I would like to have that's square on the inside so I can slide it onto the frame.
Most C channel has a thicker inside radius for strength by design. Depending on how strong you need this to be you can get a metal shop to tight bend some plate/sheet to meet your specs. If not, try fabricating what you want by taking angle and welding it together to make the desired shape and fit. Angle iron will still have a slight inside radius but, nothing like the C channel stock does.
Structural C-channel is rolled when it is formed, so the "legs" of the channel can't be exactly parallel (inside to outside). The legs are always tapered. Same thing as WF structural shapes. It's kinda hard to explain, but if they tried to make the sides parallel it puts the rolling machine in a bind.
You might be able to find something that was folded, but it will be hard to get it with sharp inner corners like that.
I have to battle with this occasionally when an engineer includes square C-channel in his design. Sometimes we weld something up, sometimes we cut square tubing, which still has an inside radius. Can you put a spacer between the frame and your C-channel to avoid hitting the inside radius?
I would be fine with a bend like rectangle tube has because the frame is rounded on the edges. The problem with channel is that it's tapered. I think I'll just get some 1/8th bent to the specs I need. I measured it the other day and it needs to be 2 1/8 inches by 4 3/8 inch. Or close to that. My design is pretty simple but the steel needed may need to be custom bent or what not.
hiya, another option would be to go to the inside rather than outside. I did this with my rear and front bumpers for the pig and used solid 1" x 3" steel and drilled thru for frame attachment. the rear of the steel pokes out for recovery points. I got this idea from one of the old bumper vendors. It's solid but on the heavy side. C channel to the inside would've probably done just as well.
He could weld on a spacer on the outside mating surface of the bummper attachment. The spacer hight would be under the width of what the total distance of what the webs in the steel.
