Guide - How to machine sew leather?

Before embarking on any leather sewing projects, we recommend that you do some 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 will be visible when unsewing!

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

SADDLESTITCH (HAND STITCHING):
The principle of the 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 stitching, the threads never cross both layers of leather. The stitching is therefore more fragile and easily and completely unravels if one of the threads breaks (e.g. second line)

Saddle stitching is therefore more aesthetically pleasing and durable than machine stitching, but requires much more time and patience. Machine stitching is ideal for joints that will not be subjected to high tension.

WHAT IS THE SEW-QUICK AWL?

The automatic awl , also called a quick seam, is a tool designed for people who are new to leatherwork: it allows you to quickly sew leather thanks to an automatic mechanism. Please note, it does not allow you to make a saddle stitch but a "machine" stitch. 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 household sewing machine and want to start sewing leather? Here are some essential points to know before you get started:

• Sewing machine: the ideal way to sew leather is to have a powerful machine with a double or even triple feed (to feed the leather more easily when sewing), otherwise you can add a double feed foot to your home machine. We do not recommend sewing leather with a low-cost home machine (e.g. Silvercrest).
  
  Unfortunately, we cannot recommend a particular machine, it all depends on the use (private or professional). We are fans of the Toyota Power Fabric (we use it for all our tutorials) but it is unfortunately no longer for sale (perhaps on second-hand sites). Singer has released a special industrial leather sewing machine - reference 9900 (we have a partnership with them - see the article sheet below) . Many machines are compatible with sewing leather, but you must inquire directly with the sellers: PFAFF Ambition 610/620 - PFAFF Passport 3.0 - Veritas Power Stitch (for example) .

• Choosing the leather: if you don't have a professional machine specifically for sewing leather, you can't choose leather that's 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 determine the maximum thickness your machine can handle, we recommend testing it first. The thicker the leather, the more powerful your sewing machine motor will need to be. Remember to adjust your machine's tension properly.

• 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 (short stitches are so close that in use they will tear the leather) .

• The spool of thread: choose polyester thread with a diameter of 0.35 to 0.50 mm (No. 40, No. 30 or No. 20) for leather goods and small leather goods.

• Clip clamps: These are ideal for assembling and holding your leather pieces together while machine sewing or gluing. They're very practical and avoid having to pierce the leather with pins. Alternatives: double-sided adhesive tape or water-based glue.
  
  Tip for the tape : make sure it is positioned in the seam allowance and not on the seam line (otherwise your needle may not appreciate it => it will "clog up").

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

• Which needle should I use for machine sewing leather? We recommend using special leather machine needles. These needles are made of hardened steel and are therefore very durable (the risk of breakage is lower). Sharp-point needle for stitching 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 shank (SIZE is the diameter of the needle shank in the Singer and American system).

Metric Number (NM) is equal to needle shank diameter x 100

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

WHICH NEEDLE SHOULD I CHOOSE ACCORDING TO THE DIAMETER OF THE THREAD?

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

Thread size 40 is generally used for small leather goods or fine leathers (e.g. clothing). Thread size 30 is used for leather goods and thread size 20 is used for saddlery.

IN ADDITION TO OUR ARTICLE:

We invite you to read blogger Jane Emilie 's article "What materials do you need to sew bags?"

SEE THE BLOG ARTICLE >

LEATHER TUTORIALS
WITH A MACHINE SEWING