Guide - How to machine sew leather?

Before embarking on leather sewing projects, we invite you to carry out tests beforehand to assess the power of your machine.

Unlike sewing fabric, there are no seam allowances to add to patterns. Don't rush when sewing leather by machine: once the leather is stitched, small holes are visible when you unstitch!

WHAT IS THE DIFFERENCE BETWEEN HAND SEWING LEATHER AND MACHINE SEWING?

SELLIER STITCH (HAND SEWING):
The principle of saddle stitch is to pass each of the two threads above and below the layers of leather. If one of the threads breaks, the seam does not come undone and can easily be repaired (e.g. second line).

MACHINE SEWING:
As for machine sewing, the threads never pass through the two layers of leather. The seam is therefore more fragile and unravels easily and completely if one of the threads breaks (e.g. second line)

Saddle stitch sewing is therefore more aesthetic and solid than machine sewing but requires much more time and patience. Machine sewing is well suited for assemblies that will not be subjected to strong tensions.

WHAT IS THE SEWING AWL?

The automatic awl , also called coud-vite, is a tool intended for people who are new to working with leather: it allows you to quickly sew leather thanks to automation. Please note, it does not allow you to make a saddle stitch seam but a “machine” seam. We do not recommend it if you want to have a solid and “traditional” leather seam.

HOW TO SEW LEATHER WITH A SEWING MACHINE?

Do you have a family sewing machine and want to start sewing leather? Here are some essential points to know before you get started:

• The sewing machine: the ideal for sewing leather is to have a powerful machine with a triple drive (in order to feed the leather more easily when sewing) otherwise you can add a double drive foot to your family machine. We do not recommend sewing leather with an inexpensive family machine (e.g. Silvercrest).
  
  Unfortunately, we cannot recommend a particular machine; it will all depend on the use (individual or professional). We are fans of the Toyota Power Fabric (we use it for all our tutorials) but unfortunately it is no longer for sale (perhaps on second-hand sites). Singer has just released their special industrial leather sewing machine - reference 9900 (we are currently testing it) . Afterwards, many machines are compatible but you must inquire directly with the sellers: PFAFF Ambition 610/620 - PFAFF Passeport 3.0 - Veritas Power Stitch (for example) .

• The choice of leather: if you do not have a special professional machine for sewing leather, you cannot choose leather that is too thick (at the risk of damaging the grain of the leather and your machine).
  We therefore advise you to select thin and supple leathers (0.8 to 1 mm - maximum 1.2 mm thick) – for example leathers from the Sweet 2, Granite or even Satinlys range.

• To find out the maximum thickness that your machine can support, we invite you to carry out tests beforehand. The thicker the leather, the more powerful the motor of your sewing machine will need to be. Don't forget to adjust the tension of your machine correctly.

• Stitch length: set your machine to a long stitch (but not too long) to prevent the leather from tearing: a stitch length of 3 to 3.5 mm (the short stitches are so close that with use they will tear the leather) .

• The spool of thread: choose polyester thread with a diameter of 0.35 to 0.50 mm (N°40, N°30 or N°20) for leather goods and small leather goods.

• Clip pliers: they are ideal for assembling and holding your leather pieces during machine sewing or gluing. Very practical, they avoid piercing the leather with pins. The alternatives: double-sided adhesive tape or water-based glue.
  
  Tip for the adhesive tape : make sure that it is positioned within the seam allowance and not on the seam line (otherwise your needle may not like it => it will "clog").

• Teflon / non-stick presser foot: to more easily feed your piece of leather and have regular stitches (on sale on our site).

• Which needle to machine sew leather? We recommend that you use special leather machine needles. These needles are made of hardened steel and therefore very solid (the risk of breakage is lower). Sharp-tipped needle for pricking leather. Size (NM) 90 to 120.

HOW TO READ A NEEDLE PLATE?

Needle size is often referred to as NM or SIZE which both represent the diameter of the needle shaft (SIZE is the diameter of the needle shaft in the Singer and American system).

The Metric Number (NM) is equivalent to the diameter of the needle shank x 100

In the example below, the needles have a NM 110 and SIZE 18. The diameter of the needle is therefore 1.1 mm (110/100 = 1.1).

WHICH NEEDLE TO CHOOSE BASED ON THE DIAMETER OF THE THREAD?

Here is a table (given for information only) to guide you.

Wire diameter	NM Needle
Polyester thread n°40 – Diameter 0.35 mm	90 - 100
Polyester thread n°30 – Diameter 0.41 mm	100 - 110
Polyester thread n°20 – Diameter 0.50 mm	110 - 130

Thread No. 40 is generally used for the creation of small leather goods or with fine leathers (e.g. clothing). Thread No. 30 for leather goods creations and Thread No. 20 for saddlery.

IN ADDITION TO OUR ARTICLE:

We invite you to consult the article by blogger Jane Emilie “What material to sew bags?”.

VIEW BLOG ARTICLE >

LEATHER TUTORIALS
WITH MACHINE SEWING