The Type Of Sewing Machine You Need To Sew Leather

[Wizcrafts]

Wiz,

Thanks for all the great information! I read your take on "industrial strength" junk on Ebay.

I'm in the market for an entry level (inexpensive) industrial machine for leather upholstery and motorcycle seats.

<snip>

I see posts for various machines locally on Craigslist, but I am concerned about their age/condition/history for the price. Should I try to find an older Japan-made model or new(er) Chinese model for same money?

Your guidance is greatly appreciated.

You're welcome!

If all you plan to sew is leather seating, not 4 layer holsters or heavy straps, a flatbed walking foot machine with reverse is all you need. Try to find a Japanese built Consew 206RB-x (where "x" is the version number; 5 is current), or Juki, Mitsubishi, National, or Seiko compound feed walking foot machine (or maybe a West German built Adler or Pfaff). They have solid moving parts made of quality steel. The castings are very good, bearings are hefty, bobbins for some of these models are 50% larger M style, and the newest model's pressor feet lift almost 1/2". I don't know what the differences are in the Chinese built model that is now for sale. Couple that with a 1/2 horsepower clutch or servo motor, with a 2" pulley and you can sew everything from couch covers to motorcycle seats. You can always swap the pulley and v-belt to a bigger 3" set for more speed on cloth and vinyl upholstery jobs.

Another good thing about commercial walking foot machines is the mind boggling amount of pressor feet and binding attachments available for them.

Items sold on CraigsList can be great deals, or nightmares. One advantage of buying locally is that you can at least see and try out a machine before buying it. You don't get that opportunity when you purchase online. I found my JP built National 300N walking foot machine on CraigsList and couldn't be happier. It is almost the same as a Consew 206RB. All I changed was the motor and belt to a gear reduction servo motor, with a 2" pulley, from Toledo Industrial Sewing Machines. It uses series 135x16/17 needles, available up to #25 and sews 3/8" of harness leather without bogging down.

[glennaycock]

You're welcome!

If all you plan to sew is leather seating, not 4 layer holsters or heavy straps, a flatbed walking foot machine with reverse is all you need. Try to find a Japanese built Consew 206RB-x (where "x" is the version number; 5 is current), or Juki, Mitsubishi, National, or Seiko compound feed walking foot machine (or maybe a West German built Adler or Pfaff). They have solid moving parts made of quality steel. The castings are very good, bearings are hefty, bobbins for some of these models are 50% larger M style, and the newest model's pressor feet lift almost 1/2". I don't know what the differences are in the Chinese built model that is now for sale. Couple that with a 1/2 horsepower clutch or servo motor, with a 2" pulley and you can sew everything from couch covers to motorcycle seats. You can always swap the pulley and v-belt to a bigger 3" set for more speed on cloth and vinyl upholstery jobs.

Another good thing about commercial walking foot machines is the mind boggling amount of pressor feet and binding attachments available for them.

Items sold on CraigsList can be great deals, or nightmares. One advantage of buying locally is that you can at least see and try out a machine before buying it. You don't get that opportunity when you purchase online. I found my JP built National 300N walking foot machine on CraigsList and couldn't be happier. It is almost the same as a Consew 206RB. All I changed was the motor and belt to a gear reduction servo motor, with a 2" pulley, from Toledo Industrial Sewing Machines. It uses series 135x16/17 needles, available up to #25 and sews 3/8" of harness leather without bogging down.

Thanks, Wiz.

Another question:

There's a video from Sailrite comparing servo motors to their MC-SCR drive. They claim that when set on the lowest speed that servo motors have very little torque. I'm currently running a Singer 301. It generally does fine for two layers of leather, but when running over seams making 3 layers, it just needs a little more umph! How does the SewPro 500GR overcome the torque problem at slow speeds?

[Wizcrafts]

Thanks, Wiz.

Another question:

I'm currently running a Singer 301. It generally does fine for two layers of leather, but when running over seams making 3 layers, it just needs a little more umph! How does the SewPro 500GR overcome the torque problem at slow speeds?

The Singer 301 is an aluminum body slant needle quilter's machine, with a permanent, built-in direct drive old motor. It was designed and constructed to sew garments and quilts, not leather. That motor lacks the power to penetrate dense material of any kind.

If you are thinking of replacing the built-in gear drive motor on the Singer 301 with an industrial servo motor, forget it! That machine is not designed to take any external motor, including home sewing machine motors, much less an industrial motor. The SewPro 500GR is a big, industrial motor that mounts to the underside of a 20"x48" industrial k-legs table and uses a long v-belt in a pulley to pulley drive system, with a 3/8" wide x 1/4" thick, automotive style belt.

The SewPro 500GR, rated at 300 watts, has a built-in 3:1 gear reduction system and a 2 inch output pulley. I have never turned the speed limiter knob on the back below 50%. I usually leave it on full speed and let my foot control the speed. I have found that if the motor can turn itself over it can also turn the machine over. I have no doubt that this motor could start a Harley. It would be neat to put one into a G scale model train locomotive. It develops 1500 rpm at full speed, at the spindle.

The SewPro is a great addition to an actual industrial sewing machine, but is useless on your Singer home style machine.

[glennaycock]

The Singer 301 is an aluminum body slant needle quilter's machine, with a permanent, built-in direct drive old motor. It was designed and constructed to sew garments and quilts, not leather. That motor lacks the power to penetrate dense material of any kind.

If you are thinking of replacing the built-in gear drive motor on the Singer 301 with an industrial servo motor, forget it! That machine is not designed to take any external motor, including home sewing machine motors, much less an industrial motor. The SewPro 500GR is a big, industrial motor that mounts to the underside of a 20"x48" industrial k-legs table and uses a long v-belt in a pulley to pulley drive system, with a 3/8" wide x 1/4" thick, automotive style belt.

The SewPro 500GR, rated at 300 watts, has a built-in 3:1 gear reduction system and a 2 inch output pulley. I have never turned the speed limiter knob on the back below 50%. I usually leave it on full speed and let my foot control the speed. I have found that if the motor can turn itself over it can also turn the machine over. I have no doubt that this motor could start a Harley. It would be neat to put one into a G scale model train locomotive. It develops 1500 rpm at full speed, at the spindle.

The SewPro is a great addition to an actual industrial sewing machine, but is useless on your Singer home style machine.

No, no...I'm not thinking about replacing the motor on the 301. That's just what I inherited from my grandmother, and it sews 3-4oz leather pretty well. I'm looking for an industrial model, like a Consew 206RB as you suggested. I'm pretty sure that I don't want a clutched motor, but I wanted to make sure that a servo motor would meet my needs.

I'm working a local deal for a Japan-made Seiko walking foot, so hopefully that works out.

[Wizcrafts]

No, no...I'm not thinking about replacing the motor on the 301. That's just what I inherited from my grandmother, and it sews 3-4oz leather pretty well. I'm looking for an industrial model, like a Consew 206RB as you suggested. I'm pretty sure that I don't want a clutched motor, but I wanted to make sure that a servo motor would meet my needs.

I'm working a local deal for a Japan-made Seiko walking foot, so hopefully that works out.

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.

[glennaycock]

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.

[glennaycock]

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.

[Wizcrafts]

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.

[glennaycock]

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?

[Wizcrafts]

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 October 8, 2010 by Wizcrafts