Wizcrafts

The Type Of Sewing Machine You Need To Sew Leather

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The SewPro 500GR will fit that machine. You will need a shorter v-belt. Figure 1 inch for the closer mounting position, then another inch for each half inch smaller pulley size than the original. I bought a new v-belt, 2 inches shorter, when I got my SewPro, but that was insufficient for full adjustment. So, I bought one 3" shorter and it allows the best range of adjustment and tightness. Your setup may vary. Just remember that the angle of the control arm under the motor may dictate where within the adjuster bolt you need to be. All the way up or down may put too much strain on the arm, causing erratic speed control.

The guy with the Seiko was a flake. I found a practically new Consew 206RB, identical to the Seiko, here locally. Going to pick it up tonight. I may still order the GR500.

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The guy with the Seiko was a flake. I found a practically new Consew 206RB, identical to the Seiko, here locally. Going to pick it up tonight. I may still order the GR500.

I got a steal of a deal on a practically new, Japan-made Consew 206RB-5 with servo motor. Man, that is one bad mother! I'm impressed.

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I got a steal of a deal on a practically new, Japan-made Consew 206RB-5 with servo motor. Man, that is one bad mother! I'm impressed.

Congratulations! You have scored one of the best JP built machines for both leather and upholstery use. Just don't try to do saddlery or heavy strapping over 3/8" with it. The pressor feet will lift higher than the needle's capacity to sew effectively.

You can use up to #207 bonded thread on top and bottom and a #24 or #25 needle (135x16 leather point). Many people prefer to use a size smaller in the bobbin, but that's up to you. The 206RB uses a large M bobbin.

If the pulley is too large for you to control at slow speed, buy a 2 or 2 1/4 inch pulley and shorter belt. Switch to the original pulley and belt for upholstery sewing at higher speeds.

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Congratulations! You have scored one of the best JP built machines for both leather and upholstery use. Just don't try to do saddlery or heavy strapping over 3/8" with it. The pressor feet will lift higher than the needle's capacity to sew effectively.

You can use up to #207 bonded thread on top and bottom and a #24 or #25 needle (135x16 leather point). Many people prefer to use a size smaller in the bobbin, but that's up to you. The 206RB uses a large M bobbin.

If the pulley is too large for you to control at slow speed, buy a 2 or 2 1/4 inch pulley and shorter belt. Switch to the original pulley and belt for upholstery sewing at higher speeds.

Thanks, Wiz.

What I discovered after playing with it a bit is that the servo won't even turn the machine unless it's set to about half-speed. I can control it easily, but it doesn't have much torque. You recommend getting the 500GR?

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Thanks, Wiz.

What I discovered after playing with it a bit is that the servo won't even turn the machine unless it's set to about half-speed. I can control it easily, but it doesn't have much torque. You recommend getting the 500GR?

Play with it at different speed settings for another day, then decide if the motor needs to be replaced. Since you can control it past the 50% speed setting, see if it produces enough torque to penetrate 3/8" of belt leather, with the largest needle size you expect to use, with the heaviest usable thread in it. You may have to do this with the limiter on full, feathering the floor pedal.

I found that it was very difficult for my 500GR equipped National to penetrate hard black belt leather, with a #25 needle, threaded with #207 thread. Once I reduced the needle size to a #22 and the thread to #138, the machine began sewing normally.

Measure the diameter of the pulley on the motor. If it is over 2.5" buy a smaller pulley and belt. That adds torque. A speed reducer wheel system magnifies torque tremendously, but destroys all top end speed in the process. I had a speed reducer equipped Adler flatbed that only delivered a couple of stitches per second, at full speed. It was too slow for my liking.

A SewPro 500GR has built-in 3:1 reduction and will out-perform a standard servo motor of similar rating. See what the wattage and horsepower ratings are on your servo motor. My machine only bogs down when I stuff very dense leather under the foot and try to sew with a big needle and thick thread. Hand wheeling it usually helps.

A 1/2 horsepower clutch motor is still more powerful than a similarly rated servo motor. That will change as more SCR DC controlled systems are deployed. Those systems are very expensive at this point in time.

Eventually, your Consew 206 RB will run into other limitations that will prevent it from sewing dense leather projects. One limitation is the two pressure springs over the inner and outer feet. You may have them both screwed all the way down and find that some leather will still lift with the ascending needle. This causes skipped stitches. That machine probably has the toughest springs made for it. Your only option would be to find an extra heavy duty set of feet, with a wide inside foot (1/4"+). The wider the feet, the more pressure they exert on the material.

Machines that are built to sew harness, tack and saddles are usually equipped with extra heavy duty pressure springs and feet that are capable of holding down very thick leather (~3/4"). They also have very long needles that move much farther than the series 135x16 used in your Consew 206RB.

Edited by Wizcrafts

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Measure the diameter of the pulley on the motor. If it is over 2.5" buy a smaller pulley and belt. That adds torque. A speed reducer wheel system magnifies torque tremendously, but destroys all top end speed in the process. I had a speed reducer equipped Adler flatbed that only delivered a couple of stitches per second, at full speed. It was too slow for my liking.

...

A SewPro 500GR has built-in 3:1 reduction and will out-perform a standard servo motor of similar rating. See what the wattage and horsepower ratings are on your servo motor. My machine only bogs down when I stuff very dense leather under the foot and try to sew with a big needle and thick thread. Hand wheeling it usually helps.

A 1/2 horsepower clutch motor is still more powerful than a similarly rated servo motor. That will change as more SCR DC controlled systems are deployed. Those systems are very expensive at this point in time.

Eventually, your Consew 206 RB will run into other limitations that will prevent it from sewing dense leather projects. One limitation is the two pressure springs over the inner and outer feet. You may have them both screwed all the way down and find that some leather will still lift with the ascending needle. This causes skipped stitches. That machine probably has the toughest springs made for it. Your only option would be to find an extra heavy duty set of feet, with a wide inside foot (1/4"+). The wider the feet, the more pressure they exert on the material.

Machines that are built to sew harness, tack and saddles are usually equipped with extra heavy duty pressure springs and feet that are capable of holding down very thick leather (~3/4"). They also have very long needles that move much farther than the series 135x16 used in your Consew 206RB.

The motor is a 1/2-horse Consew CSM400. I ordered a 2-inch wheel. Just out of curiosity, is the handwheel normally difficult to turn? It's so hard it feels like the machine is binding, but if I tip it back so that the belt is slack it turns just fine. I wonder if it's just the servo motor or if the motor has a bad bearing. Do you know if there are larger handwheels available for the 206RB? I am also considering buying a reducer if the smaller pulley doesn't help, but the 500GR is only $50 more...

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The motor is a 1/2-horse Consew CSM400. I ordered a 2-inch wheel. Just out of curiosity, is the handwheel normally difficult to turn? It's so hard it feels like the machine is binding, but if I tip it back so that the belt is slack it turns just fine. I wonder if it's just the servo motor or if the motor has a bad bearing. Do you know if there are larger handwheels available for the 206RB? I am also considering buying a reducer if the smaller pulley doesn't help, but the 500GR is only $50 more...

LOL!

The servo motor has a brake. You have to apply a tiny amount of pedal, with your toe, to release the brake. If the motor can be turned without releasing the brake, it will slip when you try to sew thick, or dense leather.

There aren't any larger flywheels made specifically for the Consew walking foot machines. I went through this with my National, which is a Consew clone. You might could kit bash a larger flywheel onto it, but no guarantees. Imagine the torque you'd get if you could fit the wheel or upper pulleys off a Singer patcher, or 132k6, onto a Consew or clone!

Go with the 500GR motor, rather than the speed reducer. Once reduced, always reduced. With the gear-reduction motor, you can still get a relatively quick stitch rate, when you need it.

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LOL!

The servo motor has a brake. You have to apply a tiny amount of pedal, with your toe, to release the brake. If the motor can be turned without releasing the brake, it will slip when you try to sew thick, or dense leather.

There aren't any larger flywheels made specifically for the Consew walking foot machines. I went through this with my National, which is a Consew clone. You might could kit bash a larger flywheel onto it, but no guarantees. Imagine the torque you'd get if you could fit the wheel or upper pulleys off a Singer patcher, or 132k6, onto a Consew or clone!

Go with the 500GR motor, rather than the speed reducer. Once reduced, always reduced. With the gear-reduction motor, you can still get a relatively quick stitch rate, when you need it.

Doh! I knew it had to be something stupid like that. I didn't get any documentation with it, and the only manual I could download was hard to read. Thanks, Wiz!

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Corvus   

Thanks for these articles, they have really help to clear up some of my confusion about machines. I'm wondering where the Tippmann Boss machine fits into all this though.

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Thanks for these articles, they have really help to clear up some of my confusion about machines. I'm wondering where the Tippmann Boss machine fits into all this though.

The Tippman Boss fits into your shop for short stitching runs (a hundred stitches, or so), or intricate stitching patterns that you can't control with a motor-driven machine, or on location at flea markets or craft shows. It is a great prototyping machine. It is not a production machine, nor is it meant to be.

Production machines for leather shops are stronger than upholstery machines and run slower. Slower speeds lead to less wear on the moving parts, less distortion of shafts inside bearings - due to lower heat generation, and less skipped stitches in your leather projects. Leather sewing machines have heavier pressor foot springs, beefed up pressor feet, larger feed dogs, longer needles, bigger bobbins and shuttles and usually, much bigger flywheels. The guides that keep the needle bar moving forward and backward are larger than the guides on upholstery machines. There is at least one brand of leather stitcher that uses a square drive system, where the needle bar is orchestrated to pull straight back and forward again, rather than the typical pivoting at the top. This causes the holes to be absolutely in line, even through 1 inch of leather. The Campbell-Randall and Union Lockstitch machines also feature square drive, but don't mention it in their ads.

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Corvus   

Thank you for your reply Wizcrafts, that helps too although in the end I've still got to try and make a decision on what I think I can use. Availability of this sort of machine seems not so good in the UK but maybe I haven't dropped on the right place to look as yet.

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Jin w   

What a great information. I have never sew leather but I do have Adler 267 triple feed walking foot industrial sewing machine that I use for other heavy duty sewing machine.

Jin.

I have finally managed to take a series of photos and reduce them enough to be able to post several in one reply. The following photos are from my National 300N heavy duty walking foot machine. Similar to a Consew 206RB, it is capable of sewing a little over 3/8", depending on the density of the leather and needle and thread sizes. It handles a range of thread from #69, up to #207 - bonded nylon or polyester. It takes series 135x needles from #14 (smaller available, but not recommended), up to #25, max. These photos show it with a #22 leather point needle and #138 Weaver nylon thread (messy), which was used to sew suede lined guitar straps and rifle slings.

This is a serious leather and vinyl sewing machine! I have replaced the clutch motor with a servo motor I bought from Bob Kovar, at Toledo Industrial Sewing Machines. It is geared down internally and has a 2" pulley. It produces the equivalent power of a 1/2 to 3/4 hp clutch motor and has a top speed of 1500 rpm. The motor draws no power until you apply the floor pedal to it.

One more thing, the bobbins on this type of walking foot machine are known as M style bobbins and are 1 inch in diameter. They have a higher thread carrying capacity than standard industrial machine bobbins.

Walking Foot sewing machine, with compound, triple feed.

post-11118-12793035986_thumb.jpg post-11118-127930360244_thumb.jpg post-11118-127930360574_thumb.jpg post-11118-127930360928_thumb.jpg post-11118-127930361266_thumb.jpg post-11118-127930361554_thumb.jpg post-11118-127930358861_thumb.jpg post-11118-127930359145_thumb.jpg

post-11118-127930359483_thumb.jpg More pressor feet (inner and outer sets) for a compound feed walking foot machine. These are known as 111 series feet, named after the famous Singer 111 walking foot machines, of antiquity (but still in service!). If there is a job to be done that needs a special foot, you can find one for any industrial machine that uses series 111 pressor feet.

post-11118-127930388605_thumb.jpg Last, but not least, here is a close-up, left side view, of my Union Lockstitch needle and awl stitcher sewing about 50 ounces of hard belt leather. The top of the needle is barbed. The thread is fed into the barb through a thread guide and looper arm, that revolves around the lifted needle. The needle then goes down, where a revolving pickup point grabs the loop off the barb, under the throat plate, and carries it around the bobbin shuttle. This machine is capable of some very serious sewing! The photo shows it threaded with #277 bonded nylon, top and bottom, which is in the low range of the weights it can manage. I have sewn with #550 thread on a Union Lockstitch machine!

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Ferg   

[Does anyone know what brands/make of sewing machines Toledo Industrial Sewing Machines Sells?

ferg

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CJ1,

When you say "posted" do you mean on YouTube, Twitter, or on leatherworker.net?

Mike

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CJ1,

When you say "posted" do you mean on YouTube, Twitter, or on leatherworker.net?

Mike

Mike;

Who are you replying to? Is this in the wrong topic?

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Great information and vids. Thanks for taking the effort!

Question: Is that "swing arm edge guide" something that comes standard with sewing machines like this or is that something you rigged-up yourself? I am researching a machine to sew leather upper material to foamy/cushiony material. I'm making beach style flip-flops.

Thanks again.

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Great information and vids. Thanks for taking the effort!

Question: Is that "swing arm edge guide" something that comes standard with sewing machines like this or is that something you rigged-up yourself? I am researching a machine to sew leather upper material to foamy/cushiony material. I'm making beach style flip-flops.

Thanks again.

The swing away guide was added on. They don't come with any machine as standard equipment. Bob Kovar, of Toledo Industrial Sewing Machines, sells the swing-away edge guides, along with bobbins, needles, thread, and parts for most industrial sewing machines. Call him at 866-362-7397 to get the current price for the guide.

Edited by Wizcrafts

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Thanks a bunch for the great info Wiz! Looks I will be making a phone call to Bob K. soon.

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ramrod   

this is really a great read, wiz. very well done.

i have questions about the machine i acquired. it's a singer 211g155. it was given to me this past week and i haven't set it up yet. it was apparently used in an awning shop. i'm wondering what the maximum thickness of leather can be sewn on it? and how about the needle and thread size recommendations for leather? is this a compound feed that was mentioned earlier? is it generally a good machine?

i also have a singer 591 that was used in a local clothing factory. it seems to be a real beast and seems to punch through anything, but i've never gotten it to run perfectly.....skipped stitches and all. can you tell me anything about this one?

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this is really a great read, wiz. very well done.

i have questions about the machine i acquired. it's a singer 211g155. it was given to me this past week and i haven't set it up yet. it was apparently used in an awning shop. i'm wondering what the maximum thickness of leather can be sewn on it? and how about the needle and thread size recommendations for leather? is this a compound feed that was mentioned earlier? is it generally a good machine?

i also have a singer 591 that was used in a local clothing factory. it seems to be a real beast and seems to punch through anything, but i've never gotten it to run perfectly.....skipped stitches and all. can you tell me anything about this one?

This is something that should go into its own new topic. Post it anew and I will answer your questions.

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ramrod   

DOH! you're right. i'll get it posted elsewhere.

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[Does anyone know what brands/make of sewing machines Toledo Industrial Sewing Machines Sells?

ferg

Toledo sells a lot of the Cowboy brand sewing machines, as well as a large selection of used machinery and they are also dealers for most of the major brands such as Adler and Consew and many others. They are one of our biggest dealers for Cowboy Sewing Machines.

Edited by neelsaddlery

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This would be a good time to compare home vs industrial motors and needles. You depend on the turning power of the motor to get the first stitch into your material, and the horsepower determines how easy or hard that will be. Once it gets the machine sewing, almost any home style sewing motor will run a sewing machine at a decent rate of stitches per minute, up to its gearing limit. But, that speed is usually only attainable if you remain within the practical limits of material density, needle and thread size. The bigger the motor, and higher its horsepower rating, the more dense the material it can try to penetrate. Most industrial sewing machines come with either a clutch or servo motor, which is mounted under the work table, which the machine rests on top of. A v-belt connects the pulley on the motor to the pulley cast into the flywheel (handwheel) on the back of the machine.

Industrial sewing machines are usually fitted with a motor pulley that best suits the intended work. Upholsters and garment makers want high speed, so they order a large motor pulley, somewhere in the vicinity of 3 to 4 inches diameter, inside the groove. The pulley on the flywheel of garment machines is typically around 4 inches diameter, so these machines are often running at close to 1:1. Industrial clutch motors run at 1725 rpm, at 120 volts, or 3450 rpm at 220 volts (3-phase), so a machine running a 1:1 ration to the motor will sew at that speed. If you were to purchase a used garment sewing machine, even with a 120 volt motor, a 1:1 pulley ration may be uncontrollable for the untrained sewer. A smaller motor pulley is the answer to that problem.

Most leather sewing machines are equipped with a 2 inch motor pulley. This not only slows the machine down to a more controllable speed, but doubles the torque. This comes in as very important when you try to sew thick or dense leather, or bio-plastic projects, or plywood covered cases. Furthermore, if you sew anything other than garment/chap leather at the high speeds used in garment machines, the friction will heat the needle to almost red hot, melting the thread, scoring the leather and usually, causing the needle to grab inside the leather, on its way back up. This causes the leather to lift with the needle. When that happens at the moment the bobbin shuttle's pickup point is passing by the eye of the needle, you will get skipped stitches.

The bigger the machine, the thicker the intended payload, the larger the needle and thread it uses, the slower it must turn. Therefore, distributors of harness stitching machines often include a speed reducer between the motor and the machine. This reduction is at least 3:1, or more. I have an Adler flatbed harness stitcher that was so geared down and its maximum speed was about 3 stitches per second, or 180 per minute. It sure could punch through 3/4" of belt leather at that speed and gear ratio!

Now, on to the pictures. The first photo shows a home sewing machine motor next to a clutch motor. The home motor is rated at 75 watts and has a 1/2" pulley. The industrial motor is a 1/3 hp 300 watt motor, with a 2.25" pulley. The home motor is suitable for driving a home machine through cloth and denim. The industrial clutch motor can sew 3/8" of leather easily with that size pulley. A 2" pulley would give it even more torque.

post-11118-127938857033_thumb.jpg

Clutch motors always run at full speed, but they develop their maximum torque when you engage the motor to the machine. You control them by means of a floor pedal, about a foot square, with a rod connecting it to a movable arm protruding down from the bottom of the motor. When you move your toe downwards on the pedal, the clutch begins to engage, turning the machine. Skilled sewers learn to control the motor from barely turning the machine, to full speed. This takes a bit of practice and the amount of toe required to feather the clutch often depends on the density of the material, and inertial resistance of the machine's mechanism. Also, since a clutch motor always runs at full speed, it always consumes electricity. When it runs under load, sewing, it consumes its rated power draw. Most industrial sewing motors come in these ratings, with the smallest meant for garment machines only:

  1. 1/4 hp
  2. 1/3 hp
  3. 1/2 hp
  4. 3/4hp

These motors have a 3/4" shaft and take pulleys made for them and the narrower, 7/16" v-belts they use.

In order to make sewing on industrial machines more controllable, and to reduce the cost of operating the machines on 110 volt circuits, servo control motors were developed. The early generation were prone to premature failure and made a lot of noise as they started up. This has been improved and in some cases, totally overcome, by new controller technologies. Industrial sewing servo motors are available in a range of power capacities from about 1/2, up to 3/4 horsepower. Their wattage ratings vary, from about 300, up to 600 w. The nice thing about all servo motors is that until you press down on the floor pedal, they do not draw more than 1 watt. You can leave a servo motor turned on all the time and not notice it in your electric bill, unless you are actively sewing a lot.

One of the shortcomings of many servo motors is a lack of startup torque. While they do produce their rated drive power at full speed, the opposite is true at slow speeds. That is another reason why many leather stitchers ship with a speed reducer pulley under the table. It doubles or triples the slow speed torque, while also reducing the maximum speed to one that won't burn up you leather and thread.

There is a new type of servo motor that has been produced, to overcome the problem of low slow speed torque. It is a gear reduction motor, currently marketed under the brand name "SewPro." I have their model 500GR. It features a 2" pulley and a speed limiter knob on the back. It runs at a maximum speed of 1500 rpm. This machine only consumes 300 watts flat out, but has a 3:1 reduction system, giving it the same power as most 3/4 hp servo motors. I have one and love it. I can sew from under 1 stitch per second, to about 10 to 12 stitches per second (depends on the diameter of the flywheel pulley). It is a bit low for upholstery, but not unacceptable. It is perfect for leather, which is what I mostly sew these days. It sews marine vinyl like it is butter.

Here is a picture of my SewPro 500GR servo motor, mounted under the table of my 75 pound National 300N walking foot machine:

post-11118-127939072772_thumb.jpg

Next, let's compare a couple of needles. The one on the left is a #12 home sewing machine needle, used to sew thin cotton thread into shirts and pants. The needle on the right is a number 25 needle (series 135x16), used to sew up to #277 nylon thread into leather holsters and straps. Home style sewing needles are not usually available in sizes bigger than #18, although I found some #20 on eBay. Series 135x16 (leather point) and 135x17 (ball point) are available in sizes up to #25. As a reference, #69 nylon thread, commonly used in upholstery and marine vinyl sewing, uses a #18 to 20 needle. Stronger results are achieved with #135/138 nylon or polyester thread, which requires a #21 or #22 needle. This leaves out all home machines, including the ones sold on eBay as "industrial strength."

Here then, are the home and industrial needles, side by each:

post-11118-127938907536_thumb.jpg

Now that you have seen comparisons of the motors and needles used by home and industrial sewing machines, you'll have a better understanding of what is required to sew leather.

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This is one of the best descriptions I have seen. I am going to mention this in my add for

Ebay when I sell my machines. These people on ebay trying to stuff 1/4" or more leather

in those machines are crazy. Those machines were not made for that type of sewing.

This was very helpful to me. I collect and sell machines and I just learned a whole lot!!!

Thanks very much....

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Content to be added and updated on an ongoing basis.

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.

Later!

Barra; Joanne; can this become a Sticky topic?

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