Wizcrafts

I used one of those until I got a walking foot machine. The OP also uses a walking foot machine and won't need the jig.

Technically speaking, your Class 4 will sew under 6 ounces, but only with very light thread, a small needle and tensions rolled almost all the way off. I actually sewed a burlap bag closed on a Cobra Class 4. I also used it to sew zippers onto vinyl jackets, some of which were 4 or 5 ounces thickness. The machine needed a lot of adjustment to do this and this takes time. Here is a checklist to use for sewing under 6 ounces of material. #69 bonded nylon or polyester thread, on top and bobbin. #18 needles (not usually available with a leather point in this size). Back off the top tension entirely. Reduce the tension on the check spring for the lightest pull that still moves it all the way up and down during the take-up cycle. You may or may not need to unscrew the bottom tension spring to reduce top tension. Adjust the bobbin tension spring down for a modicum of pull; smooth, but not tight. Don't let the screw head extend so far that the top thread gets caught on it as it feeds around the bobbin case Back off the pressure on the feet using the big threaded adjuster on top. You won't need as much force to hold the leather down. Some people do the opposite and crank up the pressure. This just pushes soft leather deeper into the feed dog hole and slot. Make sure that the presser foot go all the way down, to secure the leather between stitches If you got the blanket foot set with your machine, it may work better than the harness feet. The blanket feet are large and have teeth. The outer blanket foot also has steel all the way across the back, giving more holding power behind the needle and inner foot. This gets around the issue of soft leather lifting with the needle when using harness feet, which are wide open on the back. The blanket foot set includes a different feed dog, which has teeth. It may or may not prove more efficient than the smooth dog. Also, the blanket feed dogs tend to have a smaller needle hole than the smooth dogs have. Hold the threads back and test on some scraps of the same thickness, adjusting the top or bobbin tension springs to balance the knots. If the blanket foot is too wide, take it to a grinder and cut down the right (and/or left) toe

My advice is to ask the seller about the slow speed controllability. Have him make a short phone video of the machine in motion, from the slowest possible, to highest possible speed. If you like what you see, buy it. If you think a different motor is needed down the line, buy it. At least get some time on the machine with the motor already on it.

Ike; What caused the tension release lever to get stuck between the disks? Others will want to know.

That motor is rated at 2/5 H.P. which is a little on the low side for torque, depending on the material density and motor pulley diameter. If it has a 2" pulley, it will drive a standard walking foot machine, equipped with a #22 leather point needle, through a couple layers of belt leather.

Ah so!

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The stirrup plate is what you need to sew curved gussets. Once you will get past the thread loop position problems, you'll laugh at this beginner's speed bump. Have you ordered some leather point needles one size larger? This may solve the loops on the bottom problem. Did you know that leather points are available in more than one shape? I use mostly type S, but also have some triangular "diamond" points on hand. They produce a different top and bottom stitch. One more thing: you might try adding some more top pressure to the feet. If the leather is not absolutely pressed down against the stirrup plate it will usually have bad results on the bottom.

Here is a link to the brand new CB3200 web page

Back off the bobbin tension until there is a smooth, even pull, with a little resistance. Sew a text row of stitches on some same thickness scraps, adjusting the top tension as you sew. When the knots are in the middle, you're ready to go to work.

I use my patcher for sewing patches onto vests and jacket sleeves. It is perfect for fixing straps on sandals, ladies pumps and purses, as well as sewing pull tabs onto boots. It can sew in any direction and has a small snout, with an equally small bobbin. I limit my patcher to using #69 bonded nylon in the bobbin, which extends the life span and allows more items to be sewn You need to clean that machine, paint it and oil/grease it.

The spring guide feet tend to be more edge-guidish than the raising feet.

135 is a Canadian/European measurement thang. It is actually size T135 which equals B138. It's like the difference between dynes per cubic kilopasqual vs. inches of Mercury, for barometric pressure.

According to the manual, the feed dog teeth should be about 1 or 1.2 mm above the plane of the throat plate, at their highest point. However.....Some of us set them flush with the top of the throat plate, for mystical reasons, known only to Mr. Peabody and Sherman.

Are you using a leather point needle?

I recall a topic started by a member who purchased a similar machine from an eBay dealer (not a member of LWN) and got it in 3 boxes. She was so frustrated trying to assemble the items (without any viable instructions) that she about gave up after fighting with the parts for well over a week. It is better to order a machine from a dealer who will ship it fully assembled on a pallet and ready to use. At least have the table and its components assembled and maybe the head threaded, in a separate box. Even the step of attaching the head to the table and motor can be too much for a first time owner of an industrial sewing machine.

Back off the bobbin tension spring until the thread flows smoothly with about half the current force.

If by "topstitch foot" you mean the hinged foot with a spring guide that moves vertically in a slotted right or left toe, it is used to either follow a previous stitch line (top stitching a pattern), or for use as an edge guide. A raising foot is used to sew along the top of the right or left edge, to secure a folded hem or cuff. It can also act as a edge guide, as long as the material has a square edge.

Using #138 in the bobbin would confirm or deny the need for a larger needle, depending on the outcome. If #138 bottom thread gets properly pulled into the holes, you needed to move up 1 needle size. Note: this only applies to other leather that has the same density on the bottom. If you change to a softer bottom layer, the existing needle may suffice. FYI: I usually use a #180/24 needle with 207/207, on my CB4500. I sometimes even go down to a #23 if the work is only 7-8 ounces thick and bridle leather soft. I use my stirrup and holster plates on a regular basis and only have to either loosen the bobbin, or tighten the top tension to compensate.

Would you please post a close up photo of the thread on the bottom, with the stirrup plate installed? Additionally, please post a photo showing how you have threaded the top thread. Take it head on, from the left side of the machine, where the disks can be seen. Also, state the thread sizes and needle size.

The stirrup late raises the point of the the work, but not exactly in a linear fashion. The real difference in the thickness of the plate itself. If the original plate is 3/32" and the stirrup is 5/32", loosen the bobbin tension, or tighten the overall top tension to raise the knots. OR, increase the needle by one size. A bigger hole allows the knots to float higher.

You may have overlapped some windings on the new bobbin, causing it to bind as it feeds. Or, maybe the starting thread stub is long enough to catch on the bobbin case spring. That stub should be cut flush with the bobbin. The bobbin winder has an adjustable sliding block that the tension disks are attached to. If the bobbin winds mostly on one side, loosen the screws that secure the sliding block and move the disks to the other direction. Secure the screws and try again. There is a bent lever that flips down over the bobbin while it is winding. There is a screw on top of the lever. Adjust it away from the bobbin to load more thread.

Installing a speed reducer is not trivial for a first timer. Not only will you need to position it exactly under the flywheel on the machine, you'll also need to align it with the motor pulley. Plus, you'll need to purchase two new v-belts: 1 from the motor to the large pulley and 1 to go up from the small pulley to the machine. Once you install a reducer you will need to loosen it to remove the belt going to the head, in order to flip the head for oiling or adjustments, if any are needed. Finally, make sure that the reducer you purchase has ball bearings. In the meanwhile, a 2" motor pulley and 1 inch shorter belt will make a noticeable improvement in your low end controllability and torque. You may not need a reducer at all! But, if torque is still lacking, a better motor might make a world of difference.

There is a bobbin winder assembly on the right end of the machine. I can see it in your first photo. The big wheel on the winder gets pushed forward into the main drive belt, with a fresh bobbin mounted on the shaft on the right end of the winder. There is a lever on top of the bobbin that will get pushed up when the thread loads to whatever density that lever is set to trigger at. When the lever pops up, the wheel is pulled back, away from the drive belt. You need to load thread from a spool on the thread stand, up, then down to the back end of the winder frame. Go through whatever loops or guide holes are provided, then around a spring loaded tension disk set, then on to the bobbin. Feed the thread through a hole on the outside of the bobbin and hold it as you load the bobbin. If the bobbin loads too little before releasing, screw the lever counterclockwise to raise it and its trigger point. If the bobbin overflows, lower the lever.

You can purchase a smooth feed dog and left and right toe (plus double toe) feet from Toledo Industrial Sewing Machines, or Leather Machine Company (Cobra), or Techsew, all of which support this forum. They also carry alternate throat plates and other accessories you may need some day. Ask for accessories for a 441 clone.