convert standard crotch pattern to gusseted crotch ?

Sorry, I cannot help (nor can I imagine why such an alteration is desirable/necessary), but my search lead me to this site:

Here ya go, Robb. These are the best crotches I've seen yet:

It shouldn't... at least not if you did what I think you did. But I bet you didn't add extra torso length beyond what a pants and shirt would give you. You get a permanent wedgie if you don't.

The gusset can be shaped by cutting off the front and back crotch extensions and joining the two along the inseams... result is a long diamond. But you need all of the original width and length. The back seam of pants (good ones at least -- those McCall pants are terrible, but easy to see the skirt basis), is typically angled in at center back seam, resulting in what is in effect a long dart at center back. You've got to put that extra fabric for the dart back in when you're doing what you propose, putting the center back seam back on vertical, and then take that back out in darting or dart equivalent at the waist.

The only time I've done this (for someone who used a wheelchair and was having pressure problems from seams), I started with a custom draft and did not cant what would be the center back seam ... so I had the advantage of not needing to guess how much the patternmaker had taken out.

Kay

Thanks Kay, for the helpful description of the problem and how to solve.

I have a purchased kwik sew pattern 2704 with a seam in the center back that i want to remove.

I must have either cut the *new center back fold* too deep or did not account for a seam allowance for the gusset when i used the straight edge to follow a line parallel to the original seamed center back pattern line.

I will try again with your information handy.

Thanks again, robb

for the consideration. robb