Jenni Beth
Must Have: 5oo4's Classic One-Piece Swimsuit
Updated: Sep 15, 2021
Okay. So swim is one of my favorite fabrics to sew! I get to spring, and I seriously can't stop myself from sewing up all the swim! Plus this year, I've been testing up swim patterns. First 5oo4's Malia shorts and then 5oo4's Bethany shorts. I can't even tell you which one I like the best! But I needed a suit to photograph with them. So I decided to sew up a one-piece that I never got to last summer: 5oo4's Classic One-Piece Swimsuit for Women.

Let me back up and tell you a little bit about this suit. It is a basic one-piece. It has a high or low back, high or low front, high or low legs, and an optional keyhole. The child's version has a high or low back, but no keyhole or different front. Both the adult and the child version have a peplum skirt option that you can include if you want. But that's not the awesome thing. The awesome thing is that there's a whole class to go with it. If you purchase the class option here: 5oo4 Swim Workshop. It is a class about sewing a swimsuit, but it's also so much more than that! It has 15 modules and includes videos for both the women's and kids' swimsuits. It teaches you tips and trick for sewing with swim fabric for the first time. It gives you so many more options than are suggested in the pattern (want to skip the lining or use clear elastic instead or colorblock?) It includes 4 pattern hacks and walks you through how to do countless more. And there is a private facebook group where you can get specialized help on fitting your own body. So fun!!
I watched the swim workshop last year when the pattern first came out. And I watched it again this year when I was sewing up the women's pattern. It's just that good!! These particular suits are the high back/high front/low leg, because I wanted something that would be functional in the water for actual swimming, and I wanted this awesome fabric from Boho Fabrics to shine through!! (Isn't it so pretty!!)
Sewing it up:
The first thing you need to know about this make is what a muslin is. And about my love/hate relationship with muslins. A muslin is a test garment made from a similar fabric that you make first to make sure you get the fit spot-on before you cut into your pretty fabric. I absolutely love the idea of muslins. And I 100% expect the garment to fit correctly the first time. As any good sewist will tell you, this is unrealistic, as everybody's body is different, and a pattern cannot take all of those differences into account. You have to do it yourself. But I am eternally optimistic. So I assume that most (all?) of my sews will work out. I don't ever sew them the "cheater" muslin way where you just baste the most important pieces together to assess fit and then move onto the nice fabric. Nope. I do all the pieces and all the parts for my muslin. And I cross my fingers and hope I will get to wear it even though it's a test garment. This philosophy is called trying to make a wearable muslin.
So these are our muslins. And they look good now, but let me tell you, they did not start out that way! So I am 5'3.5" tall, so sometimes I have to shorten things. A one-piece swimsuit calls for a "girth" measurement, which is a measurement from the top of the shoulder, through the legs, and back up to that same shoulder. When I measured my girth measurement, I got 59". This put right smack-dab in the middle of sizes XS and S. So I printed both sizes, cut the length S, but then I adjusted for height to take out an inch and a half to get to my girth measurement. Then I sewed up my swimsuit all the way, adding elastic, lining, a shelf-bra, and everything else.
What I didn't realize was that when you take your girth measurement, you should measure from both shoulders and not just one. Sometimes the measurement will be different for different shoulders. And mine was different. So when I tried the suit on, it was pulling down at the bust and up at the crotch, and it was just generally uncomfortable. But I had put so much time into it that I didn't just want to throw it away. Luckily, Jessica has a section in her swim workshop on colorblocking, and she shows how to do a straight-across colorblock like the black stripe you see here. (She does it as part of a "wonder woman" suit; I just did a black colorblock). So I cut across the garment, added back in the 1.5 inches I had taken off the height. And it fit well!
Now with my daughter's suit, I was just lazy on the muslin. Jessica says over and over again in her swim workshop class that you should baste the lining and outer together before trying to add the elastic or bands. Seriously, over and over. Did I baste? Nope. I thought I could get away with not basting. Did I regret it? Yup. Lesson learned. It takes at least twice as long to unpick as it does to baste. So do it. Every time. Every single time. Also, you know they tell you to measure twice and cut once when you're building something with wood? Well when you are calculating binding length for arms and necks, you should do the math twice and cut once. When I first did it, the binding was too long, and it made the suit sit all funky on her. I was able to shorten it (when I seam-ripped and basted), and it looks pretty good. but I would not have had to spend so much time on it! By the way, if you take a classic one-piece and add the Bethany shorts over the top of it, it ends up looking like a pretty-cool retro looking suit, don't you think?! And you can't even see my colorblock! So many looks with this one!!
Lessons Learned
Bigger is better size-wise. You can always take fabric out, but it is harder to add it back in. If you're in-between two sizes for length, just go with the larger size.
Make a muslin. For real. Maybe.
Baste. Baste. Baste. When the pattern says to baste, there's a reason. It'll save you time!
When you are better with words than with math (like me), calculate the band length more than once before sewing it on, because I like my seam-ripper, but I don't love my seam-ripper.
And that's the end of my words about the Classic One-Piece. I think. Except to say that if you were wondering if you can wear it with the Malia shorts, the answer is yes!
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