Wizcrafts

Uh, NO! That guide will be totally useless for anybody wanting to actually sew leather. Those plastic body el-cheapo domestic sewing machines will break if somebody tries to sew real leather, using bonded nylon thread on them! There are entry level leather sewing machines available through our paying advertisers and they look nothing like the junk on the landing page in that sewing machine review page. It is actually just an affiliate referral page. Leather sewing machines have cast iron bodies and large moving parts and heavy bearings. Everything on them has to be beefier than cloth sewing machines to withstand the pounding from penetrating leather and pulling up bonded thread between the layers.

That IS an authentic Adler 205-370 or 374. It is not really a clone of anything --- but, Juki came out with their TSC-441 a little before Adler released the 205. Did German Adler know about the Japanese Juki and make a modified version of it? I don't know. At $2000, it is a steal! The machine listed at Weaver for over $6000 while it was in production. Be forewarned that if you need any major replacement parts, prepare to mortgage your first born. Otherwise, it uses the same needles and bobbins as the 441 clones. Protect the hook at all costs!

That is correct! Piano movers have the equipment to safely move delicate equipment up and down stairs and even through windows.

Hire a piano mover!

Juki (Japan) invented this machine around 1988 or 1989 and still makes it. The model is the Juki TSC-441. Thus, the Chinese copies are called "441 clones." I have the Cowboy CB4500 and one of my best friends has a Cobra Class 4. Same mechanism, different colors. However, my Cowboy came with stainless steel feet that don't stain wet leather.

It's an ancient Landis 1 harness stitcher. It was made to sew heavy harness, saddlery, or thick work, gun and weight lifting belts. If it comes with stock System 1000 needles (now obsolete), it can sew almost one inch. If the needle bar was lowered to use modern System 794 needles, it can sew a little over 3/4 inch.

I have this motor powering my long arm Singer walking foot machine. The motor pulley is 50mm (2") and the handwheel pulley is about 4 inches. I can set the speed limiter very low and sew at 1.5 stitches per second. I can easily single stitch by flicking the pedal and stop with the needle up or down. I have other machines that have a smaller handwheel pulley. I added speed reducers to those machines. The reducers let me sew extremely slowly; like watching grass grow slow. The speed reducers are shown on the same page I linked to earlier. I use both types.

Here is the servo motor I use.

If adjusting the tensions doesn't solve knots on the top, check the thread from the spool to the needle for binding. It could be windings cross feeding, or dropping under the spool, or twisting around posts and guides. You should raise the feet manually and pull on the thread before the needle. If it is jammed somewhere, it will be hard to pull and you can follow the path until you see the problem location. If the top path is not binding, check the bobbin to make sure the bobbin thread is actually coming out under the tension spring and that tension is being applied to the thread.

Correct! However, if one reduces the top and bottom tensions to the minimum needed to maintain a reasonably tight stitch, the thread drag will be minimized. Couple that with an aftermarket heavy duty feed dog and throat plate and a bottom feeder, coupled with a roller or Teflon foot will move leather and vinyl reasonably well. It will still be limited to fairly thin thread and needle sizes. I used this approach when I was in between being completely out of the leather business and when I began reacquiring industrial sewing machines. I had to make do with a Singer 15-91, which I beefed up as I described. It was passable until the right machines came along.

I have several Family Sew 550 watt servo motors with speed dials. I usually set them to slow speed for leather sewing. But, now and then I take in vinyl upholstery, or tarp, or banner work that involves long seams. For those I crank up the speed, re-oil the oil holes, then fire up the machine and sew flat out at about 20 to 25 stitches per second. Sometimes my partner needs to spray silicon on the needle as I sew that fast. I could probably buy a magnetic lube jar, but this doesn't happen too often any more.

This setup made my heart skip a beat! Well done Folker!

You may have to remove the foot, needle clamp and stitch regulator, unscrew the revolving head section, and pull it off the machine. leaving the needle bar attached to the take-up thread control arm. That should let you remove anything that's in the way of getting the top tension disks off. Before reassembling, oil the needle bar and the parts inside the revolving head. This would also be a good time to replace the feed motion bell crank if you are getting less than 5 stitches per inch into 6 or 7 ounces of shoe upper leather.

I was instructed by my Cowboy dealer that the best setting for most sewing on a 441 clone is to remove any leather, then handwheel the machine until the tip of the needle reaches the feed dog. Then loosen the big bolt on the crank on the back to position the inside foot to make contact with the feed dog. The results should be the best combination of lift between the inner and outer feet, in sync with the vertical motion of the needle. This should also cause the needle to pull out of the leather while the inside foot is still holding it down, preventing skipped stitches from lifting leather at the point of the lockstitch formation. The inner foot delay should also help stabilize the position of the leather so it doesn't move back as the needle ascends.

I'm pretty sure CowboyBob can get you a race cover and a cover plate.

I was responding to the feet not meeting the feed dog with the needle. You asked that on Thursday. I didn't realize you already solved that problem.

If you bought this machine (and motor) from Techsew it may still be under warranty. If so, contact them about getting the motor replaced and for tech support with any stitching problems you have been experiencing. In the meantime, unplug the motor and let it set a while. If there is a fuse, check to see if has tripped or blown and replace it (you probably got a spare fuse with the paperwork). Then plug the motor back into the AC outlet and see if it has reset itself. If a new fuse pops, or fails to reset the motor, contact Techsew for a replacement. If your machine is out of warranty, there are other servo motors you can install.

Sometimes, the top thread getting sliced is because the check spring is either not threaded correctly, or is not adjusted to keep the thread taut until the needle pierces the material.

I circled the crank you adjust to set the height of the inside foot vs the needle.

Wrong end! The crank I am referring to comes out the back near the very left side of the head. It connects to the presser foot cranks inside the left end. When you remove the faceplate you can see these parts. I'm not able to go to my shop so no photos from me at this time.

Different machines, different hooks, different feet, different springs, tensioners, guides, take-up levers, etc. Each machine has its own quirks.

Did you make an adjustment to the height of the inside foot before this occurred? If not, loosen the big bolt on the crank coming out the back left side and lower the needle to the level of the feed dog, then drop the inside foot to meet it and lock down the bolt. Maybe your bolt loosened itself. The feed dog should have risen to the top of the throat plate slot when the needle meets it, but should not start moving back at that point. Set this with the stitch lever in the zero motion position to be most accurate.

I have a Techsew 2700 (I got used) that can handle from #46 through #138 thread (using appropriate needles). I'm sure that one of the Cobra walking foot machines will have similar specs. Have you contacted Team Cobra about your concerns? I would arrange to drive there when they are open and bring your materials and thread with. If you, or they don't have #46 thread, buy a spool online and take it with you. BTW: Some invisible monofilament thread is about the diameter of #46 bonded thread. I use a #14 needle when I sew with #46 thread.

A #21 needle doesn't poke a wide enough hole to easily clear the knots from Tkt 20/#138 bonded thread. Move up to a #22/140, or #23/160 needle. The larger hole will allow the bottom thread to be pulled up with less resistance (resistance is futile!). With less resistance, you can back off the top tension and even increase the bobbin tension a bit, to get rid of the loose bottom stitches.

Did this happen on its own, without any new user action, or as a consequence of another adjustment? If an adjustment, what was it?