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This is the the last part of the maternity swimsuit construction. Click for pattern alteration and the finished swimsuit. It’s basically like putting together a swimsuit with a couple extra steps. This is just my way of putting it together, if you know or think of something better, feel free to do it your own way. Also, here’s how to sew swimsuit fabric.
First, cut out the pieces you need depending on what style you’re making. For the torso piece and bottom torso piece, cut 2 fabric pieces and 2 lining pieces.
With right sides together, the bottom torso piece can now be sewn to the torso piece.
With a stretch stitch, sew the pieces together with the torso piece up, so that when you come to the casing you can leave two holes for the ties. Remember to backstitch well at each stop. I left 1/4″ holes.
This will leave two small openings at the bottom of the casing. Sew together to lining torso but don’t leave holes.
Pin the lining piece to the fabric piece at the casing. Ignore my socked feet in the corner.
I used a double needle for this next step but you can use a basic straight stitch if you like. I used the little screw in marker to find where 5/8″ should be. Then sew down both sides of the seam. You are creating the casing between the fabric and the lining because you want the lining to stretch like the fabric.
Next, sew down the center seam stitching in the ditch. This separates the casing into two.
Make two ties by cutting out the length you want by 1″. Sew with a stretch stitch at 1/8″.
Turn them inside out.
Using a safety pin or other threading tool, thread the ties through the two casings. You can put the ties in through the holes you left at the bottom.
Sew the ties in at the top of the piece, so they are secure.
I just knotted the ends of my ties to finish them. Feel free to do it however you like.
With wrong sides together, serge or zigzag the back piece together.
Measure the side seam on the back piece. Mine is 13″.
Cut out the side seam measurement from elastic. I like using clear 1/4″ elastic. It holds up the best in chlorine, and I love how thin it is.
Pin each end to the side front.
Find the center of the elastic and pin it to the center of the fabric. Keep doing this until the elastic is pinned about every 1 1/2″.
Since I have 2:1 ratio, I have a lot of fabric to gather. If I were to do it again, I’d make it a smaller ratio to make this next step easier.
Starting in the middle use both hands to stretch the elastic to match the length of the fabric. I sewed with a wide long serpentine stitch, but you can use a zigzag stitch too. Don’t use a straight stitch.
This is what it should like like when you’re not stretching it. See how the elastic gathers the fabric?
When you get to the end, flip it around and finish the other edge.
Using a zigzag sew the side front to the side back.
Sew with the gathers up so you can make sure they’re staying even.
Your front torso piece is done! Now the rest depends on what style you have for your swim suit. Mine is a basic top so I sewed the bodice to the torso.
Make sure you secure the ties in the seam.
Sew elastic onto the empire line seam.
Secure the elastic down, by sewing with a double needle from the top.
Once I had the basic swimsuit sewn together, I put on the suit and put in the bra cups where I wanted them.