Welcome to the Leatherworker.net Leather Sewing Machines Forum! If you are new to this forum and you are seeking information about the right type of sewing machine you'll need to sew leather, you're in the right place. Everything stated below is either my honest opinion, or the honest opinions of other members of this forum. We all have personal hands-on experience sewing a broad range of leather projects on a broad range of sewing machines. Most of us have worked our way up, trying different machines, fixing up old ones, modifying them, tricking them out, all in usually fruitless efforts to sew something they are simply not capable of sewing. This is especially true when it comes to sewing leather.
Leather varies in texture, weight, stickiness, thickness, density, dryness and chemical composition. No doubt, some of you have seen pictures and videos online, showing this or that machine sewing leather. Those pictures are uploaded by the seller of the machine, to broaden their purchasing audience. What many first time sewers don't realize, is that just because a particular machine is said to be able to "sew leather," that does not mean it will do it well for the types of leather the buyer wants to sew. Leather varies, as stated above. The machines that can sew garment weight leather may not be able to sew chaps, belts, tack, holsters, or saddle bags. Just because a machine is large, or metal bodied, or or even industrial, does not make it a true leather sewing machine!
First, I will address the machines seen on eBay, sold as Industrial Strength sewing machines. Most are all metal and proudly state that fact. The sellers talk about the "powerful" 1.2 or 1.5 amp motors that are attached. Some even have ribbed drive belts and gear reduction, to eliminate slippage when sewing thick material. No doubt these are strong machines. I have a few myself. I have 2 old iron body Singers and a metal body Kenmore, even an ancient White Rotary machine. Will they sew leather? Yes, two layers of 2 to 4 oz garment leather. Will they sew leather with nylon thread? Yes, but no bigger than #69 nylon. Will they smoothly feed garment leather as it is sewn? Yes, as long as it is fairly small in size and weight and not stitcky on the top grain. If the top is sticky, no way, Jose. Sticky vinyl and leather usually gets dragged back by the top pressor foot and the stitches are either too short, or filigree the material, or skip frequently.
Sticky material, like smooth top grain chrome tanned garment leather and Naugahyde (vinyl), does not feed evenly unless the pressure on the "pressor foot" is reduced significantly. All of the feeding is done from the bottom, by the teeth in what are know as "feed dogs." The pressor foot has to apply enough pressure to the top of the material to keep it from moving between stitches and also to prevent it from lifting with the needle, as the needle begins its ascent. This is when the thread in the needle's eye forms a loop for the rotating or oscillating "shuttle" pickup point to grab. The grabbed top thread is then pulled around the bobbin case and bobbin thread, which is pulled up by the lifting take-up lever, to create the lockstitch inside the material. If the top pressure is insufficient for the thickness and density of material being sewn, the material will lift with the ascending needle and top thread. When this happens the loop may not be formed and there will be skipped stitches. Even if the material is held down by the foot to form the stitches, the spring pressure may not be enough to hold down dense veg-tan leather when the take-up lever lifts up. If the leather lifts during the take-up phase the stitch length will vary wildly, the layers may slide out of alignment and the needle may deflect and break. This can also cause skipped stitches.
In an effort to overcome the problem of feeding sticky vinyl and leather, sewing machine companies and aftermarket manufacturers produce add on pressor feet to make it easier to feed these materials. Some dealers sell replacement feet with little rollers inside them (roller feet), or teflon plastic feet that claim to allow sticky material to feed better that steel feet. Others sell actual rolling wheel pressor foot attachments and sets, where the foot, feed dog and throat cover plate are replaced as a group. Finally, you can usually find a replacement foot called an "even feed" foot, or "walking foot" attachment. It contains an inner and outer pressor foot, which alternate up and down as the needle moves up and down. This is done by a lever that is hooked on top of the needle screw on the needle bar. The inner foot presses down and moves as the needle lifts out of the material and the feed dogs pull the material back. When the feed dogs reach the preset stitch length they drop down (drop feed) and the inside foot lifts up with the raised needle bar and snaps forward. The outer foot then drops to hold the material in place until the needle has penetrated the work again and is ready to form the next stitch.
This is not a true walking foot, as is used in true walking foot machines. It is an effort to improve the feeding ability of the wrong machine for the job. An add-on walking foot will not actually help you feed heavy garments or chaps through the machine, but it will allow the leather or vinyl to move and stitch without stitcking to the bottom of the pressor foot, allowing you to increase the pressure to prevent lifting, shortened stitches, or skipped stitches. If the material being sewn is long and wide, or heavy, your machine will have trouble pulling it back to form the stitches, despite having the even feed attachment installed. There are no teeth on the bottom of the pressor feet and the material can slide easily with a little tug, or from the weight of the work folding over the front of the work table.
I have learned that these even feed attachments usually reduce the clearance under the feet. This means you cannot sew as much thickness as with the standard foot. If you raise the pressor foot bar for more clearance, the needle bar, or top thread guide on the bottom of the needle bar will hit the inner pressor foot. They are a compromise feed system.
Even if you are able to feed the material through an industrial strength sewing machine, you are going to be limited in the thickness that it can sew, as well as the size of thread it can handle and the sizes of needle it can use. Number 69 bonded nylon thread is fine for leather vests or small vinyl projects, but is not so good for upholstery or chaps, or anything thicker, like belts and bags. For these projects, you'll want to use at least twice the size of thread: #138. At this point, most home machines drop out of the picture. Even a lot of actual industrial machines will not sew with #138 or larger nylon thread. They might be able to sew soft polyester or cotton thread in larger sizes, often sold a button or topstitch thread.
To properly sew leather you need an actual Walking Foot sewing machine. In my next installment I will define the various types of walking foot machines and what makes a dedicated leather stitcher different from a leather-capable sewing machine. I have to go earn my keep now, but maybe some other members will add to this topic.
Barra; Joanne; can this become a Sticky topic?
Edited by Johanna, 10 July 2010 - 09:05 PM.
turned into a sticky- thanks Whiz!!!