See how it is done:
https://youtu.be/nRP-MMZlzJQ?si=WvohGGeEeg1CHQFt
Definitely neat. Always enjoyed the pie cuts and the forming of metal to make expansion chambers more.
That's Martin Johnson.
He made the pipes on my TDR, and is one of the nicest, most helpful fellas you'll ever meet.
Haha, just watched the vid and there's a pic of my TDR in there!
Ive seen a few guys making them using a pressure washer and they come out crap. The hand pump this guy uses seems to work really, and he makes it look so easy that I almost want to try it myself