For great fitting pants, Begin at the crotch, or How I got rid of my under the butt wrinkles!

The prevailing wisdom is that you start your fit with the waist and side seams. I can get the side seams hanging straight down the center of my legs, and not pulling front or back and the waist even and parallel to the floor, and no darts in the front, and I still have wrinkles right under my butt! Well, then, take it out of the back at the inseam. That shortens the crotch extension and now I can't sit down and have panty lines! AND I STILL HAVE WRINKLES UNDER MY BUTT! Then I read somewhere that you deepen the scoop in the crotch by 1/8th or 1/4 inch and try it on and keep doing this until you are satisfied. Well this time, I decided that since the crotch fit is always what ruins my pant fit, I will start with the crotch. I want to make a pair of gaucho pants to wear with boots this fall. I have Butterick patteren B4861.

I began by tracing off the pattern pieces. I marked the seam allowance. Then I took a flexable ruler that will bend into any shape and molded it to my back crotch. The intersection of the crotch and inseams should be at the middle to front of the vaginal opening. So I placed the end of the ruler there and shaped it up the back crotch. I then laid the ruler on the pattern with the end at the inseam and crotch SEAM line, NOT the cutting line. You can see that there is a large difference between the ruler line and the original line. I drew along the inside of the ruler. There are 2 things to note. One is that the ruler curves back in. This is because I have a sway back. If I sewed the seam angled in like the ruler, I would have way to much material in the middle of my back. I need LESS at the center back not more. So if I angle the seam the opposite way, I will decrease the amout of material up the middle of my back. This actually pulls the seam into the dip in the back at the waist and eliminates the need for the extra dart. The other thing to note is that the original pattern allowed for a 3 1/2 inch crotch extension. I know that mine is 4 and 1/2. After I drew in the new crotch line, the extension is now 4 1/2 inches!

Now I measured my seam allowance and marked my new cutting line. I already knew that I would need some extra at the hip and waist so I left an inch along the side seam in that area. It is possible to pin fit at this stage, but I can't do it very well by myself, so I cut the pattern out of some muslin and sewed the front center and back center seams and the inseams and crotch seams. Then I pinned the side seams and tried it on. NO UNDER THE BUTT WRINKLES!!!!! For the very first time, I had pants hanging straight off my butt!!! I did need some extra at the side but no more than I would have anyway. I marked my new side seams and cut out the fashion fabric. I am ready to sew!!!