I sew windlace with a 3/4" welt foot when I'm using 1/2" sponge rod, and a 5/8" welt foot when I use 3/8" sponge rod. It comes out perfect in a tenth of the time needed to glue windlace, and the rest is just how you apply it in the car.
I never cut welts of any kind on the bias, and especially when I sew vinyl. I never want to see a seam in a welt, ever. This case was an unusual one where the corner of the car's door was on a severe angle, and of course that would be hard to do with any fabric. The point is, he got it fixed and it's fine now.
No one lives forever, the trick is creating something that will.
Last edited by DanTwoLakes; 03-07-2013 at 08:06 AM.