This is hands down the best method for sewing narrow hems on thin fabrics. The trick is to stitch a row of straight stitches close to the edge and then use that row of stitches as a guide when folding the fabric. Plus as a bonus, I will show you how to avoid twisted seams when hemming, which can be a problem when hemming thin fabrics, especially if the hem is curved.
- A sewing machine
- An iron
- An awl or some other sharp object
- A thinner sewing thread (optional, but I will explain why it can be beneficial further down)
How to Sew a Narrow Hem on Thin Fabrics
1. Sew a row of stitches to use as a folding guide
Start by sewing a row of straight stitches around 1 cm (⅖ in) from the edge. The row of stitches will be used as your guide when you are folding the hem.
You generally don’t need to overcast the edges since the seam will be closed. There might be exceptions to this rule, but I’ve never had a hem unravel using this method since a big chunk of fabric will be enclosed and secured with the first row of stitches. Omitting overcast stitches will also make the hem less bulky and neater.
2. Fold the fabric, using the stitch as your folding guide
Press over the fold to make it flat
3. Fold the fabric a second time to create a narrow hem
Use the edge of the fabric as your guide. Press again
4. Stitch the hem
Try to sew close to the fold to get a really neat seam. But since we are humans and not robots the fold might be a tad bit uneven so to be on the safe side, sew a little farther from the edge to make sure the seam will catch the entire fold.
Bonus tip: How to avoid twisted seams when sewing narrow hems
Sometimes a hem will end up looking twisted when sewing a narrow hem on thin fabrics. To prevent this, use an awl or another sharp tool to gently push the outer layer of the fabric towards the presser foot in a rhythmic motion. Also, this method, using two rows of stitches, will also help keep the fabric in check.
Why do straight stitches get slightly diagonal and or wavy when sewing over thin fabrics?
This phenomenon has been puzzling my mind for decades, and recently I decided to ask the questions in the Self Sewn Wardrobe Facebook group and got some fantastic answers that explain why this happens.
The gist of it is that a thin fabric doesn’t have enough thickness for the thread to fully form the twist that will make the stitch straight. To fix this issue you can either try using a thinner thread or sew over a water-soluble stabilising paper to create more thickness.
Also. I was told that industrial straight stitch machines do a better job keeping the stitches straight than regular household multi-seam sewing machines. Fascinating stuff!