If you are just starting sewing knits, this blog post may help you to navigate through main techniques of sewing knits and provide tips and tricks to achieve the best results.
Before you start, make sure that you are using a suitable for your project fabric. Stretch fabric needs to have a required amount of stretch, drape, structure and recovery that is stated within a pattern.
Every pattern we offer has instructions for using both sewing machine and serger. Do not worry if you do not own a serger yet - you can achieve a professionally looking garment without having one. However if you can get one - we would suggest you to do so - it will speed up your sewing and elevate your skills.
Standard seams
These seams are the seams that are normally connecting main pattern parts together, such as shoulder and side seams, sleeve seams and similar.
Standard sewing machine options:
1. Short zig-zag (1.6-1.8 wide, 2.6-2.8 mm long).
2. Lightning bolt/stretch stitch
3. Simple straight stitch (2.4-2.8 mm long) - only for some seams that do not require movement/stretch such as shoulder seams. Every step in the tutorial suggests seam options - check if using this seam is appropriate.
Directions:
1. Make sure you're using jersey (not stretch) needle for your sewing machine. Use 70/10 or 80/12 needle size.
2. Set up your pressure foot pressure to the lowest setting (refer to your sewing machine user manual to find the dial to adjust the pressure).
3. If you are using a fabric that curls or stretches a lot - use a stretch seam stabilizer such as Wash-away Wonder tape (here) and place it onto your fabric at the seam line.
4. Use facial tissues under your fabric if you fabric is getting into the needle plate.
5. Set up your stitch as described above.
6. Finish the seam at the seam allowance, stitch slowly and help the fabric to move forward with your fingers. Backstitch only if you're using a straight stitch.
Now that you finished the seam - you can finish the raw edge of the seam allowance with a wide zig-zag, overcasting stitch (if you have one on your sewing machine) or leave it raw as knit fabrics normally do not fray. However if you use 'loose knits' like sweater knits and similar - it may unravel. In this case I would recommend just to run a zig-zag stitch along the edge, inside the seam allowance.
Serger options:
Serge at the seam allowance trimming off any extra seam allowance left. A standard width of the 4-threads overlocker seam is approximately 1/4 in which is equal to our standard seam allowance for our knit patterns. In this case you don't have to trim any fabric at all. However it may be different for some of the seams, check in with your tutorial.
Directions:
1. On a scrap of fabric check the Differential feed settings. Increase for very stretchy knits and set to zero for regular knits (like Interlock).
2. Finish the seam at the seam allowance. Help to feed the fabric with your fingers to make sure that your fabric is not stretching too much when going between the feed dogs and the presser foot.
3. Leave approximately 5 cm / 2 in thread ends and tie them into a knot or feed through the stitching.
If your seam ended up wavy - do not worry. Press the seam with a steam iron. Pressing is not equal to ironing. Release the steam onto your seam and then press down with your iron for couple of seconds. Then wait until the steam dissipates and repeat.
Hemming
Hemming is finishing raw edges of a garment - such as bottom hem, sleeves hem and so on. For the hemming there are a lot of different options that you can try and choose which one do you like the most.
Hemming with sewing machine
When hemming with a sewing machine we recommend to use simple straight stitch for hems that do not require to stretch (for example, bottom hem of a flared skirt or a loose fitting top). For hems that require stretch or flex you can the following types of stitches:
1. Short or medium length/width zig-zag (2.4-2.8 mm length, 1.6-2.0 mm width)
2. Lightning bolt / stretch stitch
3. Triple stretch stitch
4. Decorative stretch stitches (depends on sewing machine, please check your manual)
5. Double needle straight stitch
Please note that you can hem the double folded or single folded hem. It depends on your preference. I prefer to use double folded hems as they look very neat and do not roll.
Hemming with a serger and a sewing machine
Alternatively you can combine sewing machine finish with a serger - overcast a hem, fold it under once at the stated seam allowance and finish the hem with your preferred type of stitch. This method gives a nice finish on the inside and doesn't create potential bulk from folding the hem under twice.
You can also hem with a rolled hem. Please follow your serger's user manual.
Hemming with a coverstitch machine
Coverstitch machines can stitch with a flat seam that is perfect for hemming knits. It creates a nice two lines of stitching on the right side (that look like a regular straight stitch) and a wide stitch that cover the raw hem edge on the inside. Most of ready-to-wear knit garments' hems are finished with a coverstitch machine.
Finishing edges with bands