Swimsuit Sew Along Day 1: Swimsuit Pattern Altering

Welcome to the Peek-a-Boo Pattern Shop Swimsuit Sew Along!

Sewing swimsuits is so much fun and I’m excited to have you sewing along with me this week!
swim sew along

Joining In:
I’m so excited to have you sewing along with us! Here’s how to join in the fun

1. Pick up a copy of any Peek-a-Boo Swim Pattern (Shop for Girls or Shop for Boys)
2. Check here on the blog everyday this week (see schedule below)
3. Join the Peek-a-Boo Pattern Shop Facebook Group: Participants are encouraged to post in-progress photos, ask for help and advice, etc. throughout the week
4. Upload your Finished Photo to the Sew Along Album for your chance to win a gift card!

Sew Along Winners will be drawn from the Sew Along Album for $20 store credit to Peek-a-Boo Pattern Shop
1. Fan Favorite: Based on number of photo likes
2. Designer Choice
3. Random Draw

And 1 winner will also be drawn at random to receive $30 to The Fabric Fairy! This is my go-to shop for swimwear sewing so if you haven’t grabbed supplies yet make sure you head on over 🙂 They have everything you need to make a swimsuit for your little girl or boy!

Sew Along Schedule: 

Monday: Choosing Your Size &  Swimsuit Pattern Altering Tips
Tuesday: Stitch Types Guideline
Wednesday: Elastic Application (for girls suits & boardshorts) & FOE alternative
Thursday-Sunday: Sewing/Catch-Up Days 🙂
Monday: Winners announced and a few features shared

Let’s get started!

If you haven’t grabbed supplies yet make sure you check out the Ultimate Swim Fabric Shopping Guide to help you find everything you need 🙂

Choosing Your Size:
All Peek-a-Boo patterns include a sizing chart. Make sure you read it and measure your child 🙂 Sizing runs pretty true to RTW sizing and is consistent with my other patterns. Generally you won’t need to go up/down from the size your child normally wears to get a good fit. Here’s an example of a typical size chart:
Nantucket One Piece Swimsuit yardage

Altering Patterns
With a swimsuit it’s pretty important to get a good fit (one of the great benefits of making it yourself!) so you might need to do a little tweaking to make things perfect. Anne normally wears a 4, sometimes a 5 lengthwise but has size 2/3 hips so when I make her suits I do a size 5 length and a size 3 width. Seen here in the Waikiki One-Piece

IMG_7454 IMG_7452

These alterations are fairly simple to make and it’s so worth it! This will vary some from pattern to pattern but here’s a general guideline.

One-Piece Alterations
First let’s look at sewing for a tall, slender child. Here you can see I am using a smaller width and then I continued up to the desired height. The alteration is shown with the thick black line

If you are sewing for a child who normally wears a plus/husky size you’ll want to start with the length they need and then extend out to the desired width. You can tweak this even further to best fit your child. If the chest measurement is a close match but the hips are not you can keep the chest the same and then taper out towards the hips or vice versa.


Tankini & Monaco Swim Trunks Alterations
For a super easy fit I recommend going with a tankini for the girls. As long as your child is within a size or two of their normal size you can just sew up the width they need for top and bottom (the sizes might not be the same and that’s ok) and then lengthen/shorten the top as needed.

I recommend adding to the rise of the bottoms a bit if you are sewing a size more than 1 or 2 sizes different than your child’s normal size (e.g. a 4 year old with a 12 mos. hip size). Or if you are going up a couple sizes for a plus/husky child you might want to shorten the rise slightly. It’s always best to add to the rise if you are in doubt and then you can chop it off later if you don’t need it. For the briefs style bottoms I like to just use the normal size and then take them in along the side seams instead of messing with the rise.
Boy shorts

Board Shorts Alterations
With the board shorts you have way more flexibility in the fit. Generally I would recommend using your child’s normal size and then cutting the waist elastic to get the perfect fit. Will is in the 20% for weight and just turned two and he fits in the 2t board shorts just fine (I just cinched in the elastic). He also fits in his size 18 mos. pair from last year without any trouble. If you do need to go up/down a size I wouldn’t worry about it much. Somehow I don’t have any real photos of him in his board shorts from either summer (too busy playing!) but maybe this will give you a very general idea of the fit 🙂 This same size also fit a very average size child just fine.

Come back tomorrow for some sewing tips!

2 Responses

  1. Where do you get the ties that match colors in the board shorts. I noticed on the pictures of the boys in the board shorts, the blue tie and orange tie. They are through the elastic waistband. I think they must be threaded through separately, but where do you find those?
    Thank you!

  2. Never thought about adding to the rise. Glad I opened this today! I need to sew one for my *extremely* skinny niece, and she’s 4 and measuring into 12 months!

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