Working with denim fabric

Kim Collins shares her tips on working with the working class fabric, denim

What’s not to love about denim? Its humble beginnings of the workhorse utilitarian textile, and used for work clothes, it has also been a fashion staple for the past 50 years plus. Denim is a great versatile fabric for all kinds of sewing projects but can be a little intimidating. So Kim gives us her top tips for working with denim fabric.

Pairing denim with patterns

You really need to consider the elements of the pattern you’re using to select the correct weight denim to work with:

  • Heavier weight types of denim are more suitable for sewing patterns, which are simple in design and require structure, and use straight seams such as bags, vests and alike.
  • Embellishments or details of the design such as ruffles and the likes, may not be suited for heavy weight denim.
  • Denim is a twill woven fabric that’s woven on a diagonal and isn’t suitable for obvious diagonals.
  • It’s always best to follow the lead of the designer’s pattern fabric recommendations.
  • Use a cotton wrapped polyester, or polyester thread while sewing your project for durability.
  • Use a contrasting thread colour for the topstitching.

Preparing your fabric

Before pre-washing, sew an overcast or zigzag stitch to prevent fabric fray. Pinking shears can also be used.

Raw denim, not sanforized (pre-shrunk) will shrink anywhere between 2 and 5 per cent. Take that into consideration while measuring your fabric. Prewashing 2 or 3 times in cold water with either like colours or separately is essential before cutting or sewing, as denim will continue to shrink.

TIP: Add white vinegar to the final rinse to eliminate any traces or detergent and to neutralise the PH level. Vinegar will also help retain the colour and prevent premature fading.

Machine dry until the fabric is slightly damp to prevent premature crocking or atari that will cause the dye to bleed in the creases. Press the fabric while slightly damp and lay flat to air dry.

Stitching denim

It’s best to use a fresh needle at the start of the project. Denim needles would be the best pick. Denim will dull a needle quickly so you may need to change out the needle depending on the size of the project.

Machine tension
A standard tension setting is typically a 5, but if you’re sewing a thicker denim and using a thicker thread you’ll need a looser tension. Test tensions with scraps of fabric and thread that you’ll be using for your project for the optimal tension.

Stitch length
Heavy denim should have roughly ten stitches for every 3mm (1in) and lighter weights twelve stitches/3mm (1in).

Using a sharp pair of scissors is essential. I find a rotary cutter works well too but always start with a new blade.

A 1.27cm (½in) hem is recommended to prevent roll up.

Flat felled seams are the most popular for both durability and to conceal raw edges, as well as a clean finish with a decorative top stitch. Pressing the seams throughout the process will help you achieve a crisply finished seam.

When using an interfacing, use a lighter weight fabric to preventing it from being too bulky. A fun contrasting fabric would be a fun touch.

Professional finish
Sewn denim just as any heavier woven fabrics is going to have thick layers. Pressing seams flat as well as giving each exposed raw edge a zigzag, overcast stitch or a straight stitch with a trim with pinking shears will give your seams a professional quality finish. As always, take it slow for clean straight stitches and press to set the seam before moving on to the next step.


Gutermann’s Jeans thread pack is perfect for decorative seams and denim repairs. It includes 5 reels with bi-optical colour tones of ochre, amber and dark blue to blend in with all sorts of denim to give a professional finish. There are two reels of extra strong thread in each pack to work on heavier weight fabrics. The pack is priced at £18.99 and can be purchased in the UK – click here

This featured was written by Kim Collins who lives just outside of Detroit, MI in the US with her husband, 13-year old son and their St. Bernard, Bode.
It doesn’t get any better than to bring together constant lifetime passions to create a women’s apparel sewing pattern collection.
Kim Collins’ journey in clothing design started early in life while being taught how to sew by her grandmother.
Kim Collins, designer and owner of Ann Normandy Design.

If you love this article all about working with denim fabrics then you’ll love the other features on our Learn to Sew page here.