Wizcrafts

I'll start! Make: Union Lockstitch Machine One Model, since late 1890's Max thickness: 6 layers 8 ounce veg-tan leather Thread capabilities: Bonded nylon or polyester; sizes 138 through 554. Irish Linen thread: 3 cord through 10 cord, left twist. Needle and awl system, using a barbed needle. Huge round bobbins that hold hundreds of feet of thread. Max SPI: 4 Type: Modern walking foot flat bed (e.g. Consew, Chandler, or Juki), with large bobbin Thickness: 3/8 inch, all day long Needles: System 135x15, 135x16: sizes 12 through 25 Thread handling: #46 through #207. Best when used with #138, top and bottom. Max SPI: 3 or 4 Make: Juki Model: LU-1508NH Capacity: 7/16 inch Needle system: Pfaff type 190: Needle size range: #12 through 25 Thread capacities: #46 through #207 Max SPI: ~3 Make: Singer Model: 29k172 Max thickness: 1/4 inch to 5/16 inch Needle type: 29x3, 29x4, 135x15, 135x16 Needle size range: #12 through #23 Thread capacities: #46 through #138 Max SPI: ~5 Singer Make: Singer Model: 96k40 Max thickness: approx 1/4 inch Needle system: DBx1, DBx257 Needle size range: approx #10 through #20 Thread capacity: #69 and under Max SPI: 5

I appears to have a mechanism attached to the left side of the presser foot. That suggests that it is a Singer alternating foot system, probably with a spring loaded outer foot. I had a model 132K6 that had that drive system. It was mostly useless on polished belts; the stitch length varied all over the place as the foot slipped on the top grain and snapped forward prematurely.

I cannot see the presser foot/feet on that photo. Is there any chance you can get a close up frontal photo, or even a left front side shot?

When I had a Juki LU-563 (1988), I changed the pulley on the clutch motor to a 2" or smaller size, then got a shorter v-belt to get the adjuster back into the mid-range of the threaded bolt. That was before the time of the servo motors. I replaced my last clutch motor with a SewPro 500GR servo motor, which comes with a 2" pulley. I calculated the difference in belt lengths, minus one more inch for the new smaller motor body. I unbolted the original motor and wiring and dropped the SewPro onto the bolts (table upside down for easier install), installed the washers and nuts, clamped down the new wiring harness and switch box, up-righted the table, installed the new shorter v-belt, hooked it onto the machine, and have been sewing at controllable speeds ever since. This motor will slow down to one stitch every five seconds, and speed up to about 10 stitches per second, all by the position of the foot pedal. It has a knob on the back to limit the maximum speed. If I set it at half way, it can slow stitch about 4 stitches per minute, but it loses top speed, down to about 3 or 4 per second. The motor produces its maximum torque, even at slow speeds, when the control knob is set to full speed. It has built-in 3:1 gear reduction, to help it maintain power at all speeds. I bought my SewPro 500GR and shorter belt from Toledo Industrial Sewing Machines (866-362-7397).

The advantage of buying a second machine identical to your exiting model is they can be setup the same, sharing bobbins and needles. As for the stitch quality, the Campbell-Randall-Bosworth produces the nicest stitch. The Union Lockstitch produces the second nicest and the tightest stitch. The Union sells for less money, new and used than the Campbell. Both are sold and serviced in Yoakum, Texas. There is a learning curve on either of these machines. They are totally different than a closed eye needle machine.

If you would consider a Union Lockstitch machine, mine is for sale. It is a needle and awl machine.

Contact our dealers to see if any have used or traded in 441 models. If not, look in our sewing machinery for sale, in the Marketplace section of LWN. Members who buy longer arm machines frequently sell off shorter arm models at very reasonable prices.

To sew at least 1/2 inch you should restrict your searching to either an Adler 205-374, or a Juki 441, or a clone of either machine. The Adler sews up to 3/4 inch, as does the Juki TSC 441. Both can use a #27 needle and sew with up to #415 thread. These machines, that sew over 1/2 inch, use a system 794 or 7x3 needle. Adler 205's and Juki 441's usually sell used for at least $2500 (new, they go for about $6,000). However, you can buy a brand new Cowboy, or Cobra, or Techsew 441 clone for about $2500, plus or minus. These new 441 clones sew to 7/8 inch, with #415 bonded nylon or polyester thread. New leather stitchers are sold, warrantied and serviced by our member-dealers. You can get on the phone assistance after your purchase. Try that with a used machine bought on eBay. NOT. Every sewing machine seller on eBay adds the word "Leather" to the description. They take close-up photos of the machine sewing a piece or two of leather and make it look like it is very thick and is using extra heavy thread. A close-up lens distorts reality. Those machines are actually sewing about between 3/6 and 1/4 inch total, with #69 bonded nylon thread. It takes an incredible amount of presser foot pressure to hold down 1/2 inch of veg-tan or bridle leather, when you are sewing with a #26 or 27 needle and #346 or 415 thread. Most old or upholstery grade machines cannot exert the required amount of pressure to hold the leather down as the needle ascends. This causes skipped stitches and broken needles and thread.

That is not a walking foot machine. It is a souped up electronic home machine with an even feed attachment. They are horses of a different color. Your home machines can sew about 1/4 to 5/16" of soft leather, with no larger than #69 bonded nylon thread. The largest needle you can find to fit is will either be a number 18, 19, or 20. It will not properly handle any thread thicker than #69. An industrial walking foot machine can easily sew through 3/8 inch of hard leather, using #138 thread and a #23 leather point needle. Go up to a #25 needle and you can sew with number 207 thread. Industrial walking foot machines are usually triple feed, where the feed dog, inside foot and needle all move in sync. Maximum stitch length is usually 4 to the inch; sometimes bigger. Finally, industrial walking foot machines weigh about 70 pounds and sit on top of a cutout rectangle, with an oil drip pan, in a heavy duty 1.75" thick table, which is bolted onto to a steel frame. There is a very powerful motor under the table, which drives the pulley on the back of the machine head, via a long v-belt. Typically, these motors are rated at about 1/2 horsepower. Most leather workers now use electronic Servo motors, for better control at slow speeds. In contrast, the motor on your souped up home machines will range from 1/10th to 1/15th horsepower. If you persist in sewing 5 layers of leather with your home machine it will have a very short rest of its life.The motor will probably be the first item to go.

Use the left toe harness foot. If you have a blanket foot that came with the machine, grind the right toe off and buff it smooth and use it with the binder. The blanket foot has metal in the middle, inline with the inside foot, which the harness feet lack. This could help feeding the binding onto the leather.

Try CanSew, in Montreal. They have various sizes and colors (colours in Canadian) in size 277 (T270). Most recently, US dealers were able to buy and sell Linhanyl branded nylon thread, from Brazil. Sadly, the US importer apparently stopped stocking it. I don't know all of the details, but Linhanyl is hard to get if you run out. Hopefully, someone else will import their thread, which was available in numerous colors. One could approach thread manufactures based in the USA, such as Coats. They have a minimum order requirement.

The slack in the foot mechanism is within normal operating parameters, as is the slack in the shuttle. The stitch length of 3 mm (8 per inch) maximum should only happen if you try to sew 1/4 inch of leather. Normal maximum stitch length is 5 to the inch, or 5 mm. Are you sure that the stitch length regulator puck is all the way down, with the foot raised? If not, raise the foot with the hand lift lever, loosen the regulator screw and lower the puck until it makes contact with the top of the foot, then tighten the screw down. Make sure that the sliding lift puck on the back of the long spring is moved as far to the right as possible. There is a cutout in the spring in which the puck can slide, left and right. The further left you go, the lower the lift and the smaller the maximum stitches. Make sure that there is enough spring pressure to cause the foot to grab the leather and pull it all the way back. The teeth should not be blunt, or they may slip. You only get long stitches (5/inch) when sewing thin leather; about 1/8 inch or less.

My first industrial sewing machine was a Singer 96k40, which is pretty much identical to your 96k80. I had to convert the feed system to a roller foot and matching feed dog/throat plate, to get it to sew leather. Even then, it maxed out a about 3/16 inch, with only #69 bonded nylon thread. It was okay for sewing a leather vest, but not belts and never holsters or bags/pouches. The feed was inadequate and needle size and stroke were too limited. It is a tailor's machine.

Get you some Schmetz leather point needles and see if they cure the bad loop problem. What size needle and thread are you using right now?

With the foot raised, push and pull on the foot and see if it has measurable play, forward and backward. Make sure that the sliding puck on the back of the head is not too far to the left. That decreases the lift. Most folks set the lift puck all the way to the cutout in the flat spring. Maximum lif gives maximum stitch length. If the torsion spring tension is too low you will have feed problems. Turn down the big screw over the spring on the back. Move the stitch length regulator on the back of the presser bar all the way down, with the foot in the raised position. This yields the longest stitch the machine is capable of. If excessive slack in the foot driving mechanism is to blame, you will need to replace it.

My revolving stop screw looks like it might be a 10-28, 10-32, or 3/16x, with a little more than 1/2 inch of threads. See if you can get a couple of screws with these pitches. SAE thread only.

You can get those parts from Toledo Industrial Sewing Machines.

Dropped stitches are often caused by lifting of the leather, as you are experiencing. The solution is simple: increase the top spring pressure! If your machine is a walking foot machine, and if it has two top springs for the two feet, see if the inside foot has an adjuster for its spring and tighten it down as well. If you adjust the foot pressure springs all the way down and the leather still lifts with the needle, your only recourse is to either use a smaller needle, or a wider presser foot (set) (or run the top thread through silicon or oil lube in a lube pot).

Please retime the machine by retarding the hook a few degrees. If necessary, lower the needlebar to place the loop well into the pickup point, and above the eye. Make sure that you time the machine in forward and reverse, at the same stitch length. Timing is more critical for long stitches than short, when reverse is used. If this doesn't improve the situation, change the path of the top thread so it is more inline than otherwise. Are you using typical left twist bonded thread? Is it coming off the spool easily, or with binding?

I would like to expand on my answers to questions asked about my use of Venture Tape. This is very aggressive double sided tape. It tends to cling to the needles and gum them up. The sticky tape is not too hard to remove by running your fingers down the needle, but watch out for the sharp point at the bottom! The tape does not go away as easily as glue when you slick the edges. Try to stay far enough away from the edges to allow them to be sanded and slicked without hitting the tape. If possible, lay the tape to one side of the stitch line. Walking foot, triple feed machines have less trouble from the tape than say a patcher or straight stitch machine has. I use it on every zipper replacement job, on both sides. It was originally sold to tailor shops as zipper tape. Since then it has been improved to the point that it can hold belts and purses together until you sew them. I love this Venture Tape. When I have to secure large areas, I use either rubber glue (two coats), or spray adhesive. If I have to secure a narrow area that wants to move, I prefer Barge cement.

Yes, the check spring goes between the bottom disks and the take-up lever. It sounds like you need to reduce the travel of the check spring, so the loop forms sooner. Also, change the path the thread takes from the thread stand. Try going through a top hole, around the post, then out the bottom hole, on to the top tension disks. What brand, system and number needles are you using with what thread sizes? Too big of a needle will allow the loops to collapse sooner than otherwise.

Needle getting deflected by the layers of leather and heat from friction? Check spring adjustment (more or less travel)? This affects the size of the loop. Worn pickup point is a definite possible maybe. Does your Adler use spacer shims in the shuttle? If so, does the shim match the needle size? Is there any side slack in the shuttle, that coulds cause the point to miss the loop?

Probably. Place it well inside the edge to be sanded I have sewn through this tape on every machine I have available. It does gum up the needles.

No, I don't know that. All I know is that the supplier has this product labeled as "Leather Tape" by Venture Tape. It works like a charm.

I use Venture Tape, style TPE15, which we get from Wawak, a wholesale supplier for the cleaning and tailoring trade. The tape is sold in 1/4" and 1/2" widths in large rolls. You may need a business ID and tax number to order from them.