Completed: Comox Trunks

I’ve made a piece of underwear! They’re Thread Theory’s Comox Trunks and I made them for my brother.

Thread Theory Comox Trunks

Clearly, the best part of these trunks is the elastic! I don’t have a lot of elastic in my stash and what I had didn’t feel nice enough to sit next to your skin all day long. I wasn’t very optimistic about finding anything really nice and then stumbled upon this elastic in a stall at a local weekly market. It feels very soft and it has stars on it! They also carried several different colours. Just brilliant.

These trunks were easy to make but I didn’t follow all of the construction steps. The attachment of the binding pieces to the fly seemed a bit fiddly so I simply folded the binding strips in half and used my overlocker to attach them to the front pieces. This does leave an exposed seam inside the fly but since I suspect most men don’t even use the fly I don’t think this will be a problem.

Thread Theory Comox TrunksI sewed the inside front pieces wrong sides together. As a result the seam allowance ended up inside the fly and not on the inside of the trunks, so there is one exposed seam less that might cause irritation. With hindsight I should also have done this with the binding piece for this front piece because that seam did end up on the inside of the trunks and could easily have been hidden as well.

To further reduce the number of exposed seams I used a different method for the attachment of the gusset. I now wish I had taken pictures as I worked but I promise I’ll do so if I make them again. Basically, you skip the part where the gusset pieces are basted wrong sides together and instead work with two separate pieces. Layer the two pieces right sides together with the front (or back, doesn’t matter which side you start with) sandwiched in between. Sew this seam. Then, leaving the gusset pieces right sides together stuff the entire trunks inside the gusset pieces (fabric is allowed to spill out through the sides of the gusset) until you can layer the gusset pieces right sides together with the back sandwiched in between. Make sure nothing else is caught in between and sew this seam. Now, you can pull the trunks right side out through one of the gusset’s sides, et voila, you have hidden both seams on the inside! It feels a little bit like magic. If you have constructed yokes on classic tailored shirts you might have used this technique before.

Gusset with hidden seams

Seams of the gusset are hidden in between the two gusset layers.

I used my coverstitch machine (4 threads) to attach the elastic. This worked well, but next time I should pay more attention as I am sewing because I didn’t catch the trunks in all places on the first go and had to do some fixing.

The one thing I didn’t like is how the pattern pieces are printed from the PDF. With a PDF pattern you have to do some assembling after printing and my printer tends to scale when it shouldn’t which can make it difficult to line things up. I, therefore, have a very strong preference for the layout of the pieces to be optimized so that a pattern piece is scattered across the least number of pages possible. In this pattern (PDF for size 24-36), piece 3 could have fit on 1 page instead of 2. Piece 4 could have fit on 2 pages instead of 4 and piece 5 could have fit on 1 page instead of 2. Yes, this does result in the printing of more pages, but it does also result in less taping and less fudging when things don’t line up. On some pieces text runs across the markings that you need to line up the pages which I think is a bit sloppy and could easily have been avoided.

This pattern piece sums up what I didn't like: Printed across too many pages, text is placed across the diamond that you need for matching up. The mark that indicates you need to cut this piece on the fold is place right on top of the line that you need to cut for matching up the pages which I found a little confusing.

This pattern piece sums up what I didn’t like about the PDF. It is printed across more pages than necessary. Text is placed across the diamond that you need for matching up. The marking that indicates you need to cut this piece on the fold is located right on top of the line that you need to cut for matching up the pages which I found a little confusing. I also had some matching issues, but I fully blame my printer for that problem.

To conclude, I think this is a well drafted pattern that is very quick to make. I did all of the sewing in just one evening. I can’t really say too much about the written instructions that come with the pattern because I barely looked at them. I did read the sewalong blog posts and those were definitely helpful, even if I decided to ignore some of it. The size range of the pattern seems quite large with 24-45. I made size 30 and my brother is positively skinny so I suspect this pattern might also work for teenage sons (if willing to wear mom-made underwear, that is). The pricing of the pattern is also very reasonable as the PDF version is only CAD 7.50.

Thread Theory Comox Trunks

If you are wondering why I used grey thread in my overlocker the answer is laziness. My coverstitch machine was already threaded with the dark blue thread and I didn’t feel like unthreading it…

Have you ever made underwear? I found these trunks very easy to make and am now thinking that making underwear for myself might not be as difficult as I used to think. Except for bras of course, those are on a completely different level of sewing and fitting.

April 27, 2014

Emmely Treffers

About Emmely

I am a sewing enthusiast from the Netherlands. I live in the Leiden area with my husband and two daughters and I am currently working as a senior researcher in molecular virology. With my quilting patterns and sewing blog I want to infect as many people as possible with my love for sewing.

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  1. sewstitches

    Must have a go at these when I’m more confident, you may have written your second blog piece about them by then which I’ll follow – enjoyed this, thankyou 🙂

    • Emmely

      Thank you. They’re really not difficult to make and I definitely recommend this pattern. If you omit the fly it becomes even easier. The sewalong shows how to do that.

  2. prolificprojectstarter

    I love the star elastic what a great find and what well made looking pants, does your brother like them? I bought this pattern when it was discounted for the sew along but my husband keeps making disparaging commments about it when he see’s me looking at posts about it so I’m not sure I dare sew it up.
    I’m glad I’m not the only one who has trouble matching pdf prints out, I sometimes have to choose between matching lines on one edge of the page or another and I got a new good quality printer for christmas and make sure I tick no scaling. One time I ended up with a slightly rectangular test square and didn’t know which size to make sure was 3 inches.
    I have made myself a couple of pairsmof pants from an online tutorial using old t shirts that had stretched out of shape. They’re comfy and make me smile but I bought fold over elastic for one and knicker elastic for the other and each pair used a whole pack so cost nearly £2, so they weren’t really cost effective. I’m not sure I can face unpicking elastic off knickers I’m going to throw away in order to reuse it!

    • Emmely

      Thank you! My brother wore them today and he said he liked them.
      I have a similar story. I asked my boyfriend if he would like a pair and he wasn’t enthusiastic, at all. Then I saw all these versions popping up and bought the pattern anyway when it was discounted. My solution was to make a pair for my brother for his birthday. He’s a student so he likes free garments. Perhaps you can find another man that would appreciate a pair of handmade trunks?

  3. littlesewingdreams

    Looks great! How did you finish the leg opening, simply turn under the seam allowance? Does that not wear out? I have tried making some underwear for me, but until now I did not find a pattern that I really like. Also I am still not sure when to use my serger or not.

    • Emmely

      Yes, I turned the seam allowance to the inside and stitched with my coverstitch machine. That should be durable. An overlocker gives stronger seams than a zig zag stitch but I suppose it is a little bulkier. I probably wouldn’t use it if the garment was intended to be worn under a very tight garment (e.g. leggings) because then you might be able to spot the seams. Otherwise I don’t really see a reason not to use them for the seams.

  4. butijustwantedapintofmilk

    I recko n my son would like a pair but as he’s a skinny age 7 that would require some pattern modifications!

    • Emmely

      Hmm, yes, that would require quite a lot of changes. Better wait until he’s grown a bit? Or search for a pattern that was made for younger boys to use now?

  5. Ricardo

    Looks wonderful Emmely! Well done. I’m looking into the different machine stitches I need to use to make trunks underwear, I’m a newbie so I have difficulties finding the names of each pattern. Could you please give me the names of the stitches you used for this? Alternatively if you know a website that has this info that would be awesome!! Thanks! =))

    • Emmely

      Hi Ricardo, I only made the trunks in this post but I can give you some tips. I used my overlock and coverstitch machine but you can certainly use a domestic sewing machine as well. You’ll need a basic zig zag stitch, preferably one that you can adjust the width and length of. The exact width and length of the stitch depends on the fabric that you’re using and how tight the trunks fit. A general rule is, more stretch and tighter fit means a wider stitch will be needed to accommodate for the strain the stitch will be put under when the trunks are put on and taken off. I usually do some tests on scraps first to check whether the stitch is stretchy enough. If it rips when I pull on the fabric I adjust the settings of the stitch until it doesn’t. I’d start with a stitch that has a width of 1 and a length of 1.5. I’ll start by making the stitch wider first.
      If your machine has special stretch stitches those can be an option too. I sometimes use the lightning stitch. I’ll warn you though; this stitch is an absolute pain to unpick. If you make loose fitting trunks the triple stretch stitch might also work. This stitch is very sturdy, but has less stretch than a zigzag stitch. Pictures of some other stretch stitches that your machine might have are shown on this blog:
      For attaching the elastic band in a similar way to what I did with the coverstitch machine on my pair is the three step zig zag stitch might be an option. A regular zig zag will not be sturdy enough for this method.
      I think it will also be useful to you to have a look at the post for the sew along that was done for the pattern that I used to make trunks.
      Good luck!


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