Fish-Eye Dart: Fitting Pants or Trousers

Well….I’m working on a pair of pants right now.  I made my first pair last year as part of Sunni’s (aka A Fashionable Stitch’s) Trouser Sew Along.

She did a great job and covered lots of fitting issues but I could never get that little pool of fabric at my derriere to go away.  For any of you who has ever tried making trousers I bet you know exactly what I’m talking about.

You can kinda see a hint of the break at the fullest part in my bum in the shot above, but I didn’t take any photos of the back since it wasn’t attractive. 

Here’s an image of Sunni demonstrating the baggy bit of fabric on her test muslin:

From my research there could be several reasons why this baggy bit happens and you should explore them all, as needed.  One reason could be the back crotch curve (not enough fabric-pulls at this point or too much fabric-baggs at this point), you need to let-in/take-out the inseam for more/less ease, or there’s simply just too much fabric.

When I made my first pair of trousers I tried several of the fixes (adjusting the curve of the crotch seam and letting out fabric in the inseam) but nothing helped.  It was very frustrating…  I could never tell if the fabric was pulling vs. pooling.  Crazy right!!!

Anyhow…  after searching on the web for nearly 2 hrs I think I finally have the (magical) fix for this issue!

The technique is called a Fish-Eye Dart.  I found out about this particular type of dart buried in this thread, where a girl was looking to fit her jeans.  Ann Rowley came to the rescue and described the process in the forum (which she calls a flat seat adjustment) but also added step-by-step images on flickr

I have read the fitting book for pants/trousers and I never recall coming across this technique.  I imagine I would have used it last year had I known about it….  

The procedure reminds me of a SBA.  The fish-eye dart is a horizontal dart taken underneath the bum; its fuller in the middle and tapers out on both sides to close to nothing.

 (Image is from Ann Rowley’s flickr set)

After finally finding a fix for the pooling fabric derriere issue, I’m actually excited to go and try to refit my trousers.  How crazy is that?!  I’m hoping it will end up being a magic bullet for my trouser-butt issue, but we’ll see… 

Since it took me so long to try to find a good solution, I wanted to write-up a quick post and send the word out to any of you who may be working on pants/trousers in the future.

One additional resource I found helpful was this video from a Silhouette Patterns’s webcast that  goes about fitting a pair of jeans, live.  It’s a long video and I’ve watched the first 25 minutes already and found it really informative.

As a final technical note, trousers technically shouldn’t be as fitted as pants/jeans are.   With classic trousers, fabric falling off of the derriere should fall straight down to the floor without creasing while with pants/jeans the fabric curves around the bum.  I have the same pooling issue on both pants and trousers so for the above topic I’ve used trousers/pants/jeans synonymously.

Have any of you heard or seen of this technique with fitting trousers/pants before?

In: Sewing

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Comments (10)

  1. Karin May 1, 2012 — 12:56 PM

    This is new to me and I am really glad that shared it. Pants fitting is always a challenge and any “new tools” in the box are much appreciated!

  2. Jo May 1, 2012 — 5:45 PM

    Ahh fitting, such a struggle for so many (including me)! I really hope this is your ‘magic bullet’! I have never fit trousers before so I shall simply wish you the best of luck!

  3. Amy May 3, 2012 — 5:37 PM

    I learned a lot from that video. Thanks for sharing it. I hope this type of dart fixes your fitting woes.

  4. In fitting my Clovers, and thus trying on every pair of trousers/jeans I own, I kept wanting to pinch out this exact fisheye dart! I haven’t sewn up a second pair of Clovers yet, but have watched all the videos from Kenneth King’s Jean-ius class, and you know what? He does this! My hair-brained idea was totally justified! He simply added length to the hem to make up the difference. (In writing that, I can’t remember if he pinched out a fisheye or all the way across – I’ll have to re-watch. Either way, it makes total sense to me :)

    1. Liz June 8, 2012 — 2:22 PM

      Excellent! The benefit with the fish eye dart, assuming that’s the fix you need, is that on both the inseam and the outer seam you don’t need to add any additional length to get the front and back to match. The bulk of the fabric is taken out of the middle-butt area tapering to nothing, horizontally, on both sides. So you don’t have to monkey around with other alterations to get the pieces to match up.

  5. harry from cambridge ma January 20, 2014 — 5:42 AM

    Yesterday, I bought a slightly-longer wool dress pants from banana republic. they’re fantastic. i purposely got them slightly longer, by the way.

    i own a fantastic hiking pants with darts in the knees. i love this feature because it allows bending at the knee without an increase in fabric tension in the upper thigh’s region.

    i was wondering about putting darts in the knees of my Banana republic wool pants. what are your thoughts and comments on this?

    1. Liz January 20, 2014 — 9:37 AM

      You can put a dart wherever you need one – but I have to say… I’ve never seen darts in the knees of nice dress pants. I think those seams are appropriate on hiking pants because like you said you need to bend at the knee so much when moving around a great deal. But for dress pants … It wouldn’t be my preference to do this, but you can do whatever your heart desires. :) There are no concrete rules when stitching something up for yourself.

      You could always baste the dart it and try the trousers on before cutting and stitching them for real to see if that works for you and looks fine.

      Happy Sewing!

  6. Mary Vincent December 31, 2016 — 9:22 PM

    I am looking forward to trying this fish-eye technique on my next pair of pants. I always complained (to myself) that I had a flag of extra material at the back of my pants made from almost any pattern. This was despite making the crotch depth shorter or the crotch length (back to front) shorter, My seat is a bit flat compared with my hips and stomach. Thank you!

  7. Debra July 1, 2017 — 3:26 PM

    Thank you. This is Exactly what I think I need….fish eye dart!

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