DIY Cropped Rashguard With an Open Back

Can you believe it’s halfway through the year already?! Like when the fudge did that happen? And with June comes swimming. At least in this house. My children are convinced that they are half fish and insist on spending at least 3 days a week submersed in water. And thus began my venture into swimwear sewing.

And believe it or not, this is the first swimming suit I’ve ever sewn

I know, I know. You’re shocked. Disenchanted. Disappointed at best. It’s like you don’t even know me anymore…

But this is exactly why I needed to do this. This year was the year I was gonna tackle “me made” swimwear and – spoiler alert – I’m never looking back!

Now I wanted to make the majority of my swimwear from patterns that I already owned if possible. It’s not often that I buy niche patterns like swimwear, maternity, etc. because they don’t get pulled from the cabinet enough to keep me happy. So I set off to start with something that could be easily convertible and I came across this Pinspiration photo:

I fell in love. I never thought a rashguard could be sexy but here we are. And this is what I came up with:

So let’s get started!

Things You Will Need

Swim Knit Fabric – Since we’re doing a more conservative cut suit, try to step outside your comfort zone with a fabric that’s a bit louder. A funky print is a good way to force yourself into some confidence if you’re feeling shy at the pool 🙂 I got mine at Sew Vagabond Fabrics and they have graciously given me a coupon code to pass on to you if you need some too!

Swim Lining Fabric (optional) – If you are using a lighter weight swim knit or a lighter color, you may want to use a lining fabric. You can get this at most local fabric shops. This is also necessary if you are planning on adding cups.

Swimwear Cups or Pads (optional) – Some ladies like cups, some don’t. So do your thing and get some cups if you are feeling up for it. I pinky promise it’s not hard to add them.

1/4 or 3/8″ Clear Elastic – 1 yard should be enough.

Tight Fitting Shirt Pattern – The pattern I am using for this tutorial is the Layer Me Up by Patterns for Pirates, but you can use any tight fitting shirt pattern. Just use one that you’ve sewn up before so that you are familiar with how it fits you prior to cutting into your pretty swim fabric.

Scroll down past the Pinterest image to continue on to the next page for day 1!

Can’t make yours now? Pin this image to remind you to make one later!

[nextpage title=”Day One: Prepping Your Pattern Pieces”]

So the first thing we’re going to do is adjust our front panels for a higher neckline. Like always, adjustments like this are totally optional. I wanted an extreme crewneck for mine so I raised and pulled in the neckline dramatically on my front panel piece –  about 3/4 of an inch on the sides and 5 inches up (I ended up lowering it by about an inch and a half – more on that later).

Based on my previous experience with the length of this shirt, I estimated how short I wanted to cut it for the cropped length. Keep in mind when you are choosing how high up to cut it, that we will be adding a 2.5 inch band to the bottom. This was my finished front panel piece:

Then I adjusted my back panel by pulling in the sides of the neckline the same amount as the front panel piece and raising it slightly.

Then with my back panel piece still folded I traced out and cut a half teardrop shape going down the fold line. Mine ended up being about 10 inches tall by 5 inches wide (on the fold).

Next up is the swim lining. Most RTW shirts only use lining for the front panel so that’s what I decided to do. Now you have a couple of options here. The easiest route is to cut it exactly the same as your front panel piece then sew it in at the waistband along with the side and shoulder seams. But if you don’t want your lining to extend all the way down your front panel piece, you can cut it shorter like I did.

You’ll notice that it is pulled in a little at the bottom. If you are cutting it short like I did, you’ll want to attach elastic to the bottom to keep it from stretching out. If you are small busted like me, clear elastic is just fine. If you have a large bust and need more support, opt for a thicker elastic. Cut your elastic about 1 inch shorter than the width of where it lays on your front panel piece.

Next we’ll be adding in our cups. When you shop for cups make sure to get some that are appropriate for swimwear. You don’t want your cups sagging off your boobs while you’re in the water. Typically swim pads or cups are made of foam or other materials that won’t absorb the water.

I happened to have an old swimsuit from high school that I kept pretending I’d fit into again one day so I ripped that baby out of the closet and pulled out the scissors.

Now that I’ve got myself some cups it’s time to attach them. Start by holding your lining up to your body making sure to hold the shoulder seam right at the top of the shoulder with your seam allowance taken off the top. Then awkwardly try to hold your cups over your boobs to position them correctly and pin them in place. Or have someone else do that last part for you if you know them well enough to have them casually cupping your boobs…

Please note that the little strap attaching the two cups is on the bottom and that we are attaching the cups to the wrong side of the lining.

Then go ahead and topstitch these babies in place.

Lastly, cut your sleeves according to the pattern at the desired length.

Woot woot! All of our bodice pieces are prepped! Ready to sew? Continue on to day two:

[nextpage title=”Day Two: Assembling The Bodice”]

It’s sewing time! Before we begin though, grab your clear elastic and stretch it out. Then measure your shoulder widths for your panel pieces and cut two pieces to this length.

Start by grabbing your front panel piece, front lining and back panel piece. We’re going to start by placing our lining down with the wrong side facing up. Then place your front panel piece on top with the right side facing up.

Next, place your back panel piece on top with the wrong side facing up. And finally, place your clear elastic pieces on top, dropped down from the edge by about 1/4 of an inch to account for what will be cut off for your seam allowance. Then pin all four layers together.

Serge or sew the shoulder seams together.

Now this next part you’re going to be tempted to skip. Do. Not. Do. It. Next, we will be topstitching the seam down. Do not skip this! Swimwear seams take a lot of tension and topstitching will prevent your stitches from popping or showing through on the right side. Not to mention they make your suit look professionally finished.

Topstitch with a twin needle on your sewing machine or with a coverstitch.

Next we’ll be sewing our side seams. Layer your pieces with the right side of the back panel facing up, then the front panel with the wrong side facing up, then the lining with the right side facing up. Then pin and serge or sew together.

And once again, topstitch those side seams down. (I’ll find out if you skip it. I swear I will.)

Next, grab your sleeve pieces and fold them right sides together and serge or sew them as usual. Then flip your bodice inside out and your sleeves right side out. Place your sleeves inside the bodice and pin the armscyes together with the seam of the sleeve and the side seam of the bodice aligned.

Then serge or sew the armscye and give yourself a fit check. We won’t be topstitching here because it’s impossible to get down that sleeve if you did a long sleeve like I did.

When I put it on for a fit check I wasn’t a fan of the baginess around the elbow. Most shirt patterns will look like this because, for a regular shirt, you don’t want it tight around the elbow. So if this bothers you too, pin it in how you want your fit adjusted and serge or sew it as desired.

This is also a good time to check your neckline adjustment. I decided mine was a bit too high, as you can tell from the picture below.

I decided to lower mine about 1 1/2 inches. If you need to lower your neckline fold your front bodice piece in half with the back panel pulled out of the way and pin it so that the fabric doesn’t shift around. Then mark your changes and cut it on the fold. You’ll want to cut it on the fold to ensure that the neckline stays symmetric.

Ready for the finishing touches? Continue on to day three!

[nextpage title=”Day Three: Finishes”]

It’s the final hoorah! Let’s finish this baby up and jump in the pool. Before we start though, we will be measuring a whole bunch of custom bindings and bands. In past tutorials I have had you measure 85% of the openings. This is not the measurement we will be using! Swim knit has an incredible amount of recovery and will need different percentages for these finishing pieces. Each percentage is outlined throughout the tutorial.

There is no particular order to our finishes so let’s just start with the open back because all of us are just itching to see it in all its glory ammiright?

Start by measuring the opening of your open back cut out (measure accurately, I had to take a picture of sloppy measuring because I currently only have two hands).

Take your measurement and multiply it by 0.88 (this will give you 88%). Then add 1 inch. This will be the length of your binding. Then cut your binding piece at this length with 2 inches as your width. Sew the ends of your binding together with a 1/2 inch seam allowance to make a loop.

Then pin your binding evenly around the open back cut out with the right side of the binding up against the wrong side of the bodice.

Then serge or sew it into place with a 1/2 inch seam allowance.

Next you will turn your rashguard right side out and fold down the binding by a quarter inch, then over once more and pin it down around your opening. Your seam allowance from attaching the binding should be facing up into the binding, not down towards the bodice. See the picture below.

Repeat this all the way around the opening.

Then carefully topstitch down your binding, staying close to the outside edge so that you are sure to catch the folded side.

Isn’t that just beautiful! Next let’s tackle the waistband. Start by measuring the bottom of the rashguard.

Take the total length of the bottom and multiply it by 0.91 (giving you 91%). Add 1 inch to this number. Cut out your waistband with your new calculated number as your length and 6 inches as your width. Serge or sew the ends together with a 1/2 inch seam allowance.

Fold the waistband in half with the wrong sides together so that you have a tube with the right side of the fabric on both the inside and outside of the band. Then attach it to the bodice with right sides together. Finish it by topstitching the seam down.

Now onto our neckband. Once again, start by measuring your neckline opening.

Take this measurement and multiply it by 0.9 (giving you 90%). Add 1 inch to this measurement. Cut your new neckband with this new length with 1 3/4 inches as the width then sew the raw edges together. Just like with the waistband, fold the neckband lengthwise with the wrong sides together so that only the right side is exposed. Then pin it evenly around your opening and serge or sew it on. Topstitch your seam down.

Lastly, finish your sleeves according to your pattern directions. For this top I chose the hemmed long sleeve version.

And you are finished! Stand back and take a good look at this beauty! First here she is inside out. All those flat seams from the topstitching make me happy…

And then put it on and strut your stuff!

Like this tutorial? Did you make one too? Leave a comment below and tell me how it went!

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