If you’re tempted to dive into the wonderful world of sweatshirt fabrics, I’m going to share my top tips for sewing with them. We also made a video summary of the main tips if you’d like a quickie version 😉
1) Choose an appropriate project and type of fabric
Sweatshirt fabrics are ideal for making casual clothes, loungewear and activewear. They trap warm air, so will keep you toasty in the winter, plus they are moisture-wicking, so perfect for your workout.
They usually have little stretch (although the amount does vary), so match them with a looser-fitting garment pattern that you can get on and off easily – maybe it has a zip opening, or you could make the neckband in a stretchier jersey ribbing.
This has a smooth jersey rib on the right side, and super snuggly brushed fleece on the wrong side. It can vary in weight but is usually on the thicker and heavier side. This makes it ideal for winter clothing, particularly casual wear or loungewear – like our Billie sweatshirt and dress (versions with straight sleeves), the Stella hoodie and joggers set from my book Stretch, or even the Coco dress (see tip 3). You can also wear it for your January jog, as the fleece absorbs sweat.
Do check your machine is strong enough to sew through multiple layers, or you may struggle when it comes to inserting pockets or attaching cuffs, for example.
Loopback or French terry
This is usually lighter weight and, as the name suggests, has visible loops as opposed to fleece on the wrong side of the fabric. Loopback and terry prove that sweatshirting is not just for winter. We made a sleeveless Stella hoodie dress in terry, which would make a super cute summer outfit.
2) Get any shrinkage out of the way before cutting
Sweatshirt fabric is notorious for shrinking in the wash. A few years ago I made a super snuggly Coco dress in sweatshirt fleece – but after a few washes it resembled a top more than a dress, yikes!
It’s therefore a good idea to buy a little more fabric than you need and pre-wash it a couple of times before cutting. If you notice the fabric has shrunk quite a bit in these washes, I would also suggest adding a bit of extra length to hems and sleeves to allow for future shrinkage. And avoid putting it in the tumble dryer!
3) Allow for “turn of cloth”
If your fabric is on the thicker side, it’s wise to add a little extra length to any folds such as hems, hem bands, or cuffs, to allow for “turn of cloth” – in other words, the extra fabric needed to navigate around a fold. Otherwise you will lose that length on the garment itself.
I would add around 5mm (1/4in) for each area on the pattern that has a fold or hem allowance, before cutting out the fabric.
4) Don’t let the tube throw you
Some sweatshirt fabrics come as a tube, rather than a rectangle. Not to worry – you simply need to cut the tube down its length along one of the folds, and open it out flat.
Be aware that the way the tube was folded may leave a crease or mark down the length of the fabric. Try steam-pressing it out with the iron, and if that doesn’t work, just avoid the crease when laying the pattern pieces out on the fabric.
5) Use a nap cutting layout
Fleece-backed sweatshirting has a directional pile – give it a stroke up and down, and it may feel different in each direction. So cut it out with a “nap layout”, in other words, make sure the pattern pieces are all facing the same direction when you lay them out on the fabric.
5) Fix up, look sharp… and clean up!
You can use either fabric scissors or a rotary cutter to cut sweatshirt fabric. If your fabric is on the thicker side, it can blunt the blades though. So you may need to sharpen your scissors or change the rotary cutter blade afterwards.
Cutting fleece-backed fabric can also be a messy affair, so I like to keep a lint roller handy to wipe up the fluff after cutting.
Use a ballpoint needle in your sewing machine or overlocker (serger). This has a slightly rounded tip that won’t snag the knitted structure of the fabric. Try 80/12 or 90/14, depending on the weight of your fabric.
I would also add to take care when sewing multiple layers of thick fabric, particularly if your machine isn’t the sturdiest, or if you’re using an overlocker blade to trim the seam allowances at the same time. Go slow to avoid snapped needles – and broken blades, cripes! If you’re joining three or more layers together, it can help to trim down the middle seam allowance layer(s) a little before stitching. If the needle or blade does break, make sure all parts are removed from the garment before you wear it.
7) Adjust your stitch settings
It’s always a good idea to sew a test swatch of two layers of your chosen fabric before diving into your project, so you can check the stitches and adjust the settings on your machine if needed. If I’m using an overlocker (serger), I also sew a quick test swatch any time I change the number of layers I’m joining together, and adjust the thread tension accordingly.
If you’re using a regular sewing machine, use a stretch stitch, lightning stitch or narrow zigzag, to allow the fabric to stretch without the stitches snapping. You could get away with using a straight stitch on some seams that aren’t going to stretch.
Whatever machine you’re using, if your fabric is on the thicker side, I would lengthen the stitch to 3mm (so, if I’m sewing a zigzag, I’d set it to 1.5mm wide by 3mm long). If you’re using an overlocker, increase both the stitch length and width to accommodate the bulkiness of the fabric.
You may also need to lower the thread tension dial to allow the stitches more give through those thick layers.
8) Use a stitch starter
Your presser foot may need a little leg up to get started over the initial hump of a new seam or bulky addition like a pocket. Fold a piece of scrap fabric a couple of times and wedge it under the back of the presser foot at the start of such an area to give it a helping hand to get to the level it needs to be. I love this nifty trick!
9) Choose your finish
One of the best things about knit fabrics like sweatshirting is that they don’t fray like woven garments do. So, if you’re stitching with a regular sewing machine, you can usually leave the edges raw rather than finishing them.
Having said that, if you’re using a fleece-backed fabric, you may find that the fleece sheds quite a bit. In which case, you may want to finish them with an overlocker or using a wide zigzag stitch on your regular sewing machine.
10) Clean up
And finally, show your machine a bit of TLC! The loops or fleece on the back of sweatshirt fabric can clog up the inside of your sewing machine or overlocker, potentially leading to jams and other stitching issues. Take the time to give it a quick clean with a lint brush during and after the project, including under the needle plate. Your machine will thank you!