Today we’ll be going over some techniques for sewing knit fabrics, choosing a size, fitting, and cutting out your pattern pieces.
Sewing with Knits
You can make the Moneta using a serger or a home machine. Highlighted below are some important factors to consider when working with knits.
Stitch choice is important when sewing knits. Because the fabric will be stretching as you wear your garment, the seams need to be able to stretch along with it. If they don’t, the thread will break. We certainly don’t want our dresses falling apart as we’re wearing them.
If you’re using a serger, there is automatically stretch built into the seam. The serger will attach, trim and finish every seam as it sews it. Pretty nifty!
If you’re using a home machine, you can use a zig zag stitch with a narrow width (0.5) and a medium length (2.5 on most machines). This will give the seam enough stretch to expand with the fabric. To make everything look neat and tidy you’ll also want to finish the raw edge of the seam with a separate stitch, like a mock overlock stitch or 3-step zig zag.
Your machine might also have some specific stretch stitches, like a reinforced straight stitch. Consult your manual if you aren’t sure.
When sewing knits, you should use a ballpoint needle. They are designed to push the threads aside instead of piercing them, which helps prevent runs and skipped stitches. They’re often labeled “jersey needles.” If you see needles labeled “stretch,” these are actually intended more for highly elastic materials (think swimwear).
Schmetz Needles has a great page with lots of needle types and explanations listed. I find it to a be pretty useful reference.
Unless you have a coverstitch machine, you will need to use your standard machine for hemming. A twin needle is a great hemming option. Look for one that’s a little wider (4mm or 6mm) to give you the coverstitch look you’re used to seeing on knit garments. You’ll actually thread two separate threads through your machine, one through each needle point. You can buy ball point twin needles, but if your fabric store only has universal that will work too.
For more info on hemming with a twin needle check out this tutorial on The Coletterie.
As most overlock machines are designed to sew at 3/8”, the seam allowances on knit patterns may be smaller than the 5/8″ you’re used to on woven patterns. The seam allowance for the Moneta is 3/8”. Be sure to keep this in mind while sewing.
If you are new to the world of serging, welcome! Sergers can be a little more daunting than a standard machine, so here are some tips to help your serging go more smoothly:
Follow the manual when threading. It is very important to thread a serger correctly. The separate threads must be threaded in the right sequence for everything to work properly. Many newer machines have color coding and diagrams on the inside to help you. When in doubt, refer to your manual. If you don’t have your manual you can try to find a PDF online.
Test it out. Test sewing is important when serging, as all fabrics behave a little differently as they move through the machine. Do your test sewing on the same fabric you’re using for your project. I always save some of my scraps from cutting out the pattern. Before I start serging the seams on my garment, I run a doubled over scrap through the serger to make sure the differential is set properly. Your serged seams should lay flat, and not be wavy or scrunched.
Don’t sew over your pins. While you shouldn’t do this on a standard machine either, you definitely shouldn’t do it while serging. It can wreck your serger blade, and pieces of pin can get stuck in the machine. Ouch!
Standard Machine Tips
One of the trickier parts of sewing knits on a standard machine is getting the fabric to feed through the machine properly. If you find that the fabric is getting caught up you can:
Use a walking foot. If you have a walking foot for your machine, that can help the stretchy fabric feed through more evenly.
Lower your presser foot pressure. If you machine has an adjustable presser foot pressure, try putting it on a lower setting. This means the presser foot won’t be pressing down on the fabric as hard. Sometimes this allows the fabric to move through the machine more easily.
Test it out. Save some of your cutting scraps to use as test swatches. I always test every different stitch I’m using on a knit garment to make sure the settings are good to go on that particular fabric.
If you’d like some more in-depth info, check out The Colette Guide to Sewing Knits. I personally have this book, and there is a ton of good stuff in it.
CHOOSING YOUR SIZE
Base your size choice off the size measurements listed on the back of the pattern. Don’t worry that some of the finished garment measurements are smaller than your body size. Knit garments are often designed with negative ease, meaning the finished garment is smaller than your body because the fabric will stretch to fit.
If you are falling into different sizes in the bust and waist, you can cut between sizes by blending the size lines. Just use a ruler to connect the cutting line for one size at the bust to another at the waist.
There is quite a bit of ease in the skirt (check out the finished garment measurements), so even if you are a different size in the hips you probably don’t need to do any adjusting. But if you’d like to, you can cut a different size skirt without doing any pattern alterations, because the skirt will be gathered to fit the bodice. Just make sure you cut the same size in both the front and back skirt.
If you’re in between sizes and unsure of which one to choose, I’d recommend choosing the larger size. Instead of making a muslin we’ll be fitting as we go (more on that below), and it’s much easier to take something in than conjure up extra fabric to let something out.
FITTING A KNIT PATTERN
Unlike making a woven pattern, when sewing knits you don’t often make a muslin. This is because each type of knit fabric behaves very differently. The differences can really affect the fit of the finished garment, so making a test garment out of a fabric other than your fashion fabric isn’t nearly as helpful.
Generally, you’ll just fit as you go. As you assemble the bodice, you can do quick checks to make sure the fit is shaping up the way you’d like.
If you absolutely want to make a muslin, you’ll need to buy double the amount of fabric so that you can make a practice dress before the real one.
CUTTING YOUR PATTERN
Once your fabric is prewashed and your paper pattern pieces are cut out, it’s time to cut your fabric.
Fold your fabric in half and line up your selvages, making sure that you’re folding on grain. Your fabric should lay smooth along the fold, and not have any diagonal ripples. The fabric’s visible rows of knit stitches (think a sweater but on a much smaller scale) should should be running parallel to the fold.
Then you can either pin your pieces in place or use weights to hold them down, using the pattern’s cutting diagram for guidance, and cut them out with your fabric scissors or rotary cutter.
If your fabric has a directional print, make sure you cut all pieces in the same direction. This might mean pinning some pieces to the fabric with the unprinted side facing up.
After cutting, snip out all notches. Since our seam allowance is only 3/8”, make sure you cut shallow notches.
I also find it helpful to snip the top edge of the skirt pieces right on the fold to mark the center. This will be useful when we attach our elastic. Again, make shallow snips.
You will also want to transfer all the dot marks to your pattern pieces. To do this, you can stick a pin straight through all layers then mark its place on the fabric.
If you are using a fabric with very similar or identical right and wrong sides (like a solid color), I’d recommend marking a small ‘x’ on the wrong sides of all the pieces as you cut them. You’ll thank yourself later!
You can refer to the Cutting your Fabric post in the Mabel sewalong for additional fabric cutting info and pictures.
I hope this was all helpful for you! If you have any questions, please leave a comment and let me know. Next time we’ll start sewing!