Tuesday, March 15, 2011

Making a Swimsuit - Preparations

This is the first post in at least a two-part series on how to make a swimsuit. Make no mistake - I am no expert! But I recently finished making my first tankini and was remarkably surprised at how easy it was and how few resources there are out there in blogoland on how to make one. So here you go.

First, let me say that making a swimsuit is cheap-ER than buying ready-to-wear, but isn't exactly dirt cheap. There are a few specialized supplies you'll need, and I'll break down my costs as well.

You do NOT need a serger to make a swimsuit! I only used my serger on the side seams of the first suit I completed, and I could have easily skipped that and used my machine instead.

I'll be making Kwik-Sew 3779, View B (slightly modified) which looks remarkably similar to this Miraclesuit, doesn't it? In fact, View A looks remarkably similar to this Miraclesuit! Hmmm....

You'll need a few specialized things to make a swimsuit.

First, nylon lycra fabric. Swimsuits need to stretch a LOT, so 3% lycra isn't enough. The fabric I am using is 10% lycra/90% nylon. It needs that much lycra for recovery. Thankfully, you can usually find swimsuit fabric at the major fabric chains, although the selection is horrible. I found the orange and white polka dot online at Spandex World. Another great resource is Spandex House, although you will need to call in a credit card to order with them. I paid $10 per yard for my fabric, and needed approximately one yard.

You'll also need swimsuit lining. This is a critical item because without it you'll have a bit of trouble maintaining any sort of decency. There are different levels of quality, stretch, and cost to swimsuit lining. The first piece I tried stretched quite a bit (good) but was fairly meshy and didn't recover very well (bad). Lining that doesn't recover ends up bagging in the butt when your suit is wet. I found a nice, smooth, stretchy nude lining at Joann's for $10 per yard. I only needed 1/2 yard of lining.

Another option for swimsuit lining is the more expensive Powerknit, also called Powermesh or girdle fabric (pictured below). You can find it online at Sewsassy and Spandex House, as well as eBay and a few other sources. It usually has 15% or 20% lycra, and can be used to line a swimsuit when you'd like to replicate a Miraclesuit with the control panel. It's powerful! I am not using it in this project, but in a future suit I'll be showing how to line the front with Powermesh and what a difference it makes.

Bulky Nylon thread. I used this in each of my serger loopers (dusty serger back pictured), as well as in the bobbin of my sewing machine. It stretches very nicely and can hold up to water, chlorine, perspiration and sunscreen. The downside? It's expensive. Each spool at Joann's cost $5.99, so I stock up on them when thread goes on sale. Last time I paid $3 per spool, but it should last through quite a few swimsuits. To wind my bobbin, I set the machine speed at the lowest so it wouldn't stretch the thread too tightly as it wound.

Stretch or ball-point needles. I'm using a Schmetz 75-11.

Clear elastic or swimsuit elastic for the leg and neck openings. For an under-bust shelf liner you can use regular elastic, although the type with one brushed side is more comfortable.

Another option to basting on the machine (you will be basting the lining pieces to the fabric) is to use double-sided Magic Tape, which washes away in water.

OK, I think you're ready to get started!

So, first thing? Have a little patience. Lay out your fabric and lining, and let it breathe overnight. It sounds crazy, but lycra needs to rest and retreat to its natural weave before you cut into it. If you pull it straight out of the bag and starting cutting, you can end up with pieces stretched out of shape or off grain, and when the lycra goes back to straight grain (it will go back to straight grain, I promise you) then your entire piece could be off-kilter.

Once it's laid out for a minimum of twelve hours, you can cut out your pattern. I traced my Kwik-Sew pattern onto gridded pattern paper first, making my adjustments (tankini vs. one-piece, wider straps in back, etc).

Be sure to pin within the seam allowance on nylon-lycra, as pins can leave permanent holes in the fabric.

I take my cut pieces and lay them on top of my lining fabric, cutting that with a rotary cutter. You can cut the entire thing with a rotary cutter if you have space, but sharp scissors work just as well. One tip I have is to cut your lining fabric an 1/8" of an inch smaller on the sides than your lycra. This will cause it to stretch and not bag in the center. I only did this on the bottoms.

And now you're ready to get started sewing!


  1. This is awesome!!! I need my pattern to come already!

  2. You are not only freakishly brave, you are inspirational. My only problem is that I NEED an underwire. And I do not want to make one. In your i-net travels, have you seen any I could purchase to insert? Hmmmm. Off to research.

  3. Seriously cutest bathing suit ever!! But i'm still so scared to try! I think you've helped inspire me though!

  4. @Katherine. I'm pretty sure you can buy underwire at joanns. Or use and old bras or use the lightest bra for the lining part.

  5. Awesome. I so needed this. It seems simple and can't wait to try. Thanks again. Oh and I love your fabric.

  6. Thank you for explaining so clearly. You arean excellent technical writer! I lap swim daily and suits wear out fast! I feel so brave now, I plan to follow your instructions and make my own suit.

  7. Do you think you could use the same swimwear fabric to line a swimsuit? I've never tried making a swimsuit before but just bought more lycra than I really needed I think.

  8. Do you think you can line a swimsuit using the same fabric as the outside? I'm gonna make my first swimsuit and bought more outer fabric than I probably needed.

  9. Thank you for all these great tips! Going to make my own swimsuit soon as I cannot find one that fits well for under $100 (I have a large cup size due to nursing...30G!!) I'll let you know how it goes !

  10. I love this! I'm not very handy on a sewing machine so I always buy my swimsuits but I love the look of handmade garments!

  11. THANK YOU! I am so excited to make my bathing suit!

  12. does it have to be lycra/nylon are can you use spandex as your fabric?