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Romb-like wrinkles below bum

Solveig | Posted in Fitting on

I have drafted a pants pattern and it fits nicely except that I get romb like large wrinkles in the back below the bottom when I stand straight. I have tried changing the crotch length (both increasing it and decreasing it), I’ve changed the seat depth, I’ve tried narrowing the legs in back to get rid of the wrinkling fabric, I’ve tried changing the crotch curve. Basically all changes just create new problems and do not reduce wrinkles. It seems I can find no way to get the pants to hang straight in the back. Does anyone have an idea about another change I can try? I’m becoming rather desperate :(. Are there figures that just don’t allow nicely fitting pants? Pants I purchase have the same problem, (size US 8-10 Europe 38).


  1. Tatsy | | #1

    This sounds so familiar! At first I thought the problem was bowlegs, but that still left a few fitting problems. After trying everything else, I remembered a friend telling about a woman in a fitting seminar she attended who finally solved her fitting problems by making her pants backward. So I purposely tried on the best-fitting pair I've got with the front in the back and it looked great. Now I'm trying to figure out what makes the front fit so well and how to get enough width in the body without making the legs huge. By the way, what does "romb" mean? It's not a word I'm familiar with.

    1. Solveig | | #2

      I tried turning my muslin around with the front in the back, but I still have the same problem, and of course now the front looks bad as well :). Sorry about the use of "romb" that was Swedish, it's spelled rhombus in English and is kind of a leaning "square" standing on a point, diamond.I've been trying for years to make pants that fit. I ususally end up giving up. Then another article about fitting pants come in Threads and I try again - but the wrinkles below the seat stays what ever I do.I hope you have better luck with yours.Solveig

      1. woodruff | | #4

        A lot depends on the shape of the wrinkles below the seat. If they're tight little horizontal wrinkles, it means your thighs are full. If they're vertical wrinkles, it means you have skinny thighs. But if the wrinkles are rather V-shaped, it means there is too much fabric vertically--in other words, you may have a flat backside that simply doesn't "fill out" the pattern. Imagine what happens to a length of fabric if you put a nice, round soccer ball under it compared to deflated soccer ball. ;-)Here are a couple of things to try:1. About six or seven inches down from the waist, on the back crotch seam, make a "wedge correction." This involves drawing a horizontal line across the pattern there, cutting along that line from the center back almost but not quite to the hip, and overlapping the cut edges at the center back seam. Start with a small overlap, rather than a big one. 3/9" to 1/2" is a good beginning. This will straighten the center back seam, which if quite angled is somewhat on the bias, acting like a dart and producing fullness below the bum. You may not need that fullness.2. Another thing to try is sometimes called a "fisheye dart." Here is a link to one lady's approach:http://www.cedesign.com/familyphotos/sewing/info/KK_fisheye_dart/index.html3. If you have not tried Burda pants patterns, I would recommend them trying them. Many, many women (including me, and I'm hard to fit) find these patterns require much less adjustment than other pattern lines, because they come closer to imitating the real anatomical lines of the female pelvis.4. If you can find this book by Judith Rasband, it has the best line drawings of fitting problems I have ever seen:hhttp://http://www.amazon.co.uk/Fitting-Pattern-Alteration-Multi-Method-Approach/dp/0870057758

      2. Tatsy | | #6

        Is it possible you still have too much height in the back? The main thing I found out in turning the pants around was that even though my backside is apple-shaped, it's still flat. The back seam does not move a cm. when I sit down. All the adjustments I've made to accommodate my protruding derriere have only made the problem worse. The two things that did help were making the back curve more angular and taking some of that extra fabric off the back that throws the whole garment off-grain. I actually went with a lower waistline all the way around so that the CF doesn't "bloom." Hope this helps.

  2. ljb2115 | | #3

    Have you made a "muslin" out of some expendable fabric?  It sounds as if you need to pinch out the fabric where you have the problem.  I attended a Peggy Sagers pants fitting hands-on, she used a muslin for each of us and pinched, added, etc. (slashed) and came up with a well-fitting pair of pants.  This is a long process - I know, I have spent a kings ransom on pants fitting seminars. Keep working on this - it is well worth the effort. You absolutely need a fitting partner for this process. Don't try to turn to look in the mirror to check the back.  It won't work.


    After all the problems are pinched, tucked, slashed, etc. take the muslin apart, lay the muslin on your pattern.  If you have to slash, lay a piece of muslin (or fabric being used) on grain in the slash.  You can either pin or use tape to hold the fabric until you remove the pants. This will give you a fair view of where to alter the pattern.  Also, the Palmer/Pletch fitting books and Singer's pants fitting book are wonderful guides to have handy.  Remember to use a 1" SA on the side and inseams - never on the CF or CB seam.


    Hope I haven't confused further.


  3. starzoe | | #5

    I have a flat (Scandinavian) rear and have always had trouble with that vertical extra fabric, but several weeks ago I found a solution, at least for myself. I did post about it, but not in detail, but here goes: Work on an already-finished pair of pants. I am assuming that you have the correct crotch depth, if not make this change on the finished sloper or pattern. I use the slash and overlap method at about three inches below the waistline, above the curve of the buttocks.There was no one to help when I did this next step, which took a long time by myself: On one side back , pin out the extra. This turned out to be an amount that was shaped like two darts, one after the other, from narrow to wide and then down to narrow again at the top of the leg, quite angular.Very important at this point to make either a paper or fabric pattern and transfer those markings, you will see why later. Mark the stitching line of the "dart", draw a new "straight of the goods" from the centre of the back hem up through the centre of the darts. Cut on this line.Now sew from the hem, all the way up to the top of the dart markings. The line will be quite angular. Now try on the pants. Sit down, move around. Refine the "darts" on both the pair you have worked on and on your extra paper or fabric pattern.At this point I almost had a winner, but not quite. The pants fit quite nicely but the lower back leg at the hem was narrower. Fix that on the paper pattern.When you think of it, the ordinary pants pattern has a straight of the goods line that moves at the top closer to the centre seam. Why? Because people with ample curves up there need the little bit of semi-bias to fit over their curves. We, with flat bums, don't need and don't want that extra semi-bias at all!I have since made two pair of pants, both of them fit really well: one a stretch denim and one a cotton with a little stretch, and the pair I worked on can also be worn, but it now has a seam down the back. Actually, Sandra Betzina has a pair of pants that have a seam down the back and now you can design your own - without all that bagginess.Finally, make another paper pattern (or a muslin) with all the changes.If anyone tries this (and it is a worthwhile exercise), please let me know how it works for you.Later Edit: While lying on my back, on an icebag and my feet up on the chair (eases sciatic pain, but a real time-waster), I thought of a simpler version of the above.Take a pair of pants you have made that have too much vertical bagging. Measure 1/2 of the back hem, measure 1/2 mark between centre back seam and side seam. Join the two marks. Draw some horizontal (match) lines. Mark at the top where excess begins and lower down where the excess ends. Slash between these two points and get someone else (you'll need a buddy for this) to pin in the extra. Does it look good?

    Edited 5/22/2009 3:17 pm ET by starzoe

    1. Solveig | | #7

      Thank you so much for the suggestions. Now I have new energy for more fitting attempts. I'll let you know how it goes./Solveig

  4. Teaf5 | | #8

    Do you have a short rise and flat bum?  The rise is measured from your waist down to the hard surface you're sitting on, and most manufacturers make medium- to long-rise pants and slacks.  A few manufacturers make relatively short-rise jeans and pants that fit me well but won't work for my long-rise friend of the same size.

    I have to shorten my pants patterns at least 1"-2"  about halfway between the waist and crotch to fit my very short rise; then, I have to tug up on the center back seam, dipping the waistline at least 1/2" so that the pants hang straight in the back.

    As mentioned by others, a muslin sample is really helpful.  A sewing friend once advised me to use much softer, fluid fabrics for slacks, and they turned out to be much easier to fit and more flattering, too.

    Good luck!


  5. User avater
    Sewista | | #9

    I just want to second what Woodruff said about the fish eye dart. I had this problem and it fixed it beautifully. I used the same link she offered you as it was recommended to me. Good luck!

  6. GinghamGrrl | | #10

    I'll be honest with you here, I have not made pants yet so this may not work, but this is what I would do. Get your seam ripper, tear the whole inseam out, and carefully pin them to the person you are making them for the way you want them to hang. If they are for you, you need to use a dressmaker's model or have an experienced person pin them to you. If you cut the pattern wrong, you'll have to start over. If you just sewed them wrong, the mistake should be evident to you after you refit them. Carefully take them off, leaving the pins intact. Then sew them back up removing the pins as you go. As long as you sew them correctly, they should look like they did when they were pinned on you or your model.

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