My Dart Swinger Project!

That is awesome man how did you machine out the dies? I'm assuming a milling machine?

OK here is how I did the Dies.
Cut the upper and lower plates out of flat stock using a torch and or a plazma cutter.

Then welded in the width flat stock strip. 1 1/2" for the 1 1/2" pipe and 1" for the 1" pipe.
Now here is where the good welding skills come in.

I laid in some nice corner beads with the welder to fill the roundness of the corners to fit the pipe. The weld beads laid in there really nice conforming to the corners making them round. Then finish ground them by hand with an angle grinder and a steel grinding thick disk. Finished up with a DA with 80 grit where I could, then hand sanded the rest 80 grit then 180 grit and they were ready to use.

So no I don't have an end milling machine, but I do have a great imagination . . .

They work just great, and they don't crush the corners on the bend of the pipe like the Exhaust Tubing bending machines do. Ends up looking like a mandrel bent pipe, without the expense of the mandrel bending machine and dies.