Tutorial: Adjusting Crotch Depth (OAL2018)

Good morning, everyone!

In light of the official start to the OAL2018, I wanted to share a little tutorial for a very common pants adjustment – adjusting crotch depth. Even if you are not participating in the OAL, I hope you will find this useful! As I mentioned, this is a very common adjustment (at least half of my students in every Sew Your Own Jeans workshop that I teach ends up needing to make this adjustment!) that is a lot easier than it sounds.

This is the only pants-fitting post I’ll be doing for this OAL – most other adjustments can be done after the pants are basted at the side seams. If you have more pants-fitting needs, I absolutely recommend getting a copy of Pants for Real People (which is where the image below is from) – it is a fantastic resource that is full of valuable information and my top reference book when I’m fitting pants! Another post to check out is the Common Fitting Adjustments in the Lander Sewalong!

Common Pants Fit Adjustments – From Pants for Real People

So what does it mean to adjust crotch depth? The depth (versus the length, which runs from front waist to back waist) is the distance from your waist to the bottom of your crotch – i.e., the determining factor between a drop crotch and cameltoe. If you’ve ever had a wedgie, your depth is too short. Pants crotch hanging WAY lower than your actual crotch? Your depth is too long.

Since we are all special little sewing snowflakes (sewflakes?), all of our bodies are different – even in ways that aren’t super visible. Which means that not every single pants draft is going to fit every single person flawlessly – it’s just not possible. Personally, I have found that I have a slightly shorter crotch depth and generally need to make this adjustment with nearly every single pair of pants I sew. It’s not a hard adjustment to make, but if you’ve never seen is done before, it can be a little difficult to wrap your head around. Hopefully this tutorial will give you some insight on how to do it!

First, you’ll want to make a muslin of your pants (or at the very least – a shorts version of the pants). Sew the front and back as instructed. You don’t need to include the whole fly setup (unless you want to practice sewing it!) or waistband (unless you anticipate needing to change it to a curved waistband). Pin the fly shut and move around a bit. Don’t freak out over wrinkles – muslin wrinkles like crazy (mine are extra bad because I pulled these out of my rag pile, true story) and doesn’t have as much “give” as your regular fabric. Feel where the crotch is in relation to your body – is it hanging too low and causing extra folds due to excess length? Is it all up in your business and giving you cameltoe?

For a low-hanging crotch, pinch out the excess somewhere along the depth and pin it until it feels right. DO NOT OVERPIN – you don’t want to give yourself cameltoe (learn from my mistakes, people). Walk around, make sure you can sit, and let them settle a little. Likely, you won’t need to make a massive adjustment here – between 1/4″ – 1/2″ is most common. Little tiny fractions make a big difference when it comes to fit!

If your problem is the opposite and you need to add length, the easiest way to do this is to slice across the front of the pants and insert a strip of fabric (I just pin this, although you can sew it in, too). Pull down the bottom portion until the crotch feels like it is in the correct spot, then pin to the fabric strip.

I realize you likely cannot see a difference between those two photos (I mean… I definitely can’t haha). Like I said – it’s a small adjustment, and not always visible. But you can feel it!

Check the back to be sure there aren’t any depth adjustments needed. I’d say that maybe 1 out of every 15-20 students of mine need to actually adjust the back – it’s usually all in the front. If you do need to adjust the back, do so the same way you adjusted the front. Mine looks fine, so I left it as is.

Now take your muslin off, and measure the distance from pin to fold – or the additional length added by the strip of fabric. If you are only adjusting the front, then only measure at center front. If you are adjusting front + back, measure at the side as well as the center front and center back. This is how much you need to either add or remove from the depth.

Now how to translate this to your pattern? Easy! Your pattern piece should have a lengthen/shorten line that cuts across the fly (if it doesn’t – first of all, SHAME ON THAT PATTERNMAKER, but second, it’s easy to just add it somewhere in that general area nbd). If you are only shortening the front crotch, you will cut along that line from center front *just* to the side seam. Do not cut through the side seam – you want to leave a hinge. If you are also adjusting the back, cut straight across from edge to edge.

To lengthen, spread the pieces apart until the center front matches the measurement you took, and then fill the gap with paper and tape closed. If you are only lengthening the front, it should fade to nothing at the side seam.

To shorten, overlap the pieces until the center front is overlapped by the amount you measured. Again, if you are only adjusting the front, it should fade to nothing at the side seams/hinge.

If you need to adjust all the way around to the back, you’ll want to walk your pattern pieces to make sure that the side seams still match after making your adjustment.

Finally, redraw any wonky links or curves (such as the crotch curve if you overlapped – just smooth the curve) and straighten the grainline if necessary. You will also want to shorten or length your fly pieces (shield, facing, etc) the same amount so that they match up when you sew them together. I strongly advise making another muslin as this point to be sure that they changes didn’t wonk something up. You do you, though!

And that’s it! Like I said, a really easy adjustment that can make a world of difference in how your pants fit and feel. This is definitely the most common adjustment I see in my Sew Your Own Jeans workshops, so I wanted to share it here too!

Tags: fitting, OAL2018, pants, tutorial