Wizcrafts

In the early days of the Interwebs, long before there were forums, there were special interest Newsgroups (SIGS), that used a protocol known as NNTP (Network News Transfer Protocol). A certain jargon developed among members of these SIGS, including shorthand abbreviations for commonly used words and phrases. In NewsgroupSpeak, OP stands for : Original Poster - the person who started the thread to which others were replying. Sometimes these threads became so long that the original message was lost in the ever expanding list of replies. Those who remembered the first poster's question would refer to that person as the OP. Now, I am issuing a C&C Alert to those who are from the NNTP generation. All in the know can reply with the definition of a C&C Alert.

By setting the stitch length lever in the middle you neutralize the forward/backward position of the needle bar and feed dog, taking them out of the equation. All you need to adjust it the position of the pickup point, with the needle bar in a centered position, relative to forward and backward.

Here's a thought about the old thread. Get a large enough container to hold the spool of thread. Get some clear sewing machine oil, or a couple quarts of liquid silicon and immerse the thread in the lubricant until it has thoroughly absorbed it into the windings. Remove the lube from the container and let the spool drip dry. When the dripping stops, wipe it down with a few paper towels, thread it into the machine, and see if this helps alleviate the sticking needle problem. The thread will carry the oil or silicon to the needle, which delivers it to the dry leather. Toledo Industrial Sewing Machines has Schmetz needles and nylon thread. They now carry their own brand of pre-lubricated Cowboy thread.

Try using a #26 leather point needle. #25 is minimal for 346 thread and this leather requires a bigger hole. Crank the top pressure spring all the way down. If you have a wide presser foot set, change to it. The wider the feet, the more pressure they exert per square inch. Until you get a lube pot and liquid silicon, buy a can of silicon spray and spray it on the needle as you sew. Some leather is so dry and dense that you have to sew it while it is wet. Try moistening the flesh sides and bottom before gluing them together. Stainless steel feet and throat plates are made for wet sewing. Call Bob Kovar (866-362-7397) about getting a set of his stainless feet and a throat plate.

What common machines are supposed to use system 134? The shank diameter seems wider than DBx257 (1157?) I used in my old 96k.

I have a small box full of leftover needles, in 134 R and LR and 134-35 LR. The 134 R and 134 LR needles are 1.5 inches long and 34 mm from the top of the shank to the eye. The 134-35 LR measure 1 5/8 inches stem to stern, and are 38 mm from the top to the eye. Both systems appear to have the same diameter shank: about 5/64" I'm not sure which were for the Pfaff zigzag head I used to own, and which were used on my 96k40, perhaps with the needle bar raised.

I use either #138 or #277 for belts, depending on how thick they are. #138 is fine for thinner belts, up to about 12 ounces combined, with a suede lining. Once I cross 1/4 inch, I like #277, top and bottom, for the greater strength per stitch. This calls for a #26 needle. I sew with #138 thread on my flatbed National walking foot machine. I can sew about a dozen belts per bobbin load (large M bobbin), with #138 bonded nylon thread. I use a #23 leather point needle. The #277 is sewn on my Union Lockstitch machine. Its bobbins hold about one hundred yards of #277 thread.

TT; A walking foot machine has the correct feed system for leather, but more is needed to actually sew the stuff properly. Let's take one machine as an example. The Consew 206RB-5 This sewing machine has triple feed. The needle, inner presser foot and feed dog all move in concert, to feed the material. While the material is in motion the outer foot is lifted up. When the feed reaches the end of its stitch length, the needle begins to ascend, the feeder drops under the surface, and the outer foot lowers to secure the material. Finally, the inside foot lifts off and moves with the needle to prepare for the next stitch. The feed dog begins to raise up just as the needle and inner foot make contact with the top of the material and so it continues. As normally setup (for upholstery), this machine sews really fast and furious. I'm talking about 3000 stitches per minute! If you sewed a leather belt at that speed it would catch on fire! So, the first thing one must do to an upholstery class machine is to slow it waaaaaaay down. This can be done by means of changing the motor pulley to one much smaller, adding a 3:1 speed reducer pulley, or swapping out the motor for a servo motor, with a small pulley. Next, the top tension spring that ships with the machine is light weight and best suited to tensioning up to #92 bonded nylon thread. It will tension #138, but will have trouble pulling the knots up into a thick payload. So, a leather machines seller may change that spring to give you more top tension. A stock 206RB type is expected to sew through relatively soft loads, like denim, upholstery leather, Naugahyde, cloth seat covers, etc. To sew harder tempered leather we need to change the needles to leather point needles. Larger needles are needed to poke a hole that is large enough to pull the knots well up into the hard leather. Sometimes this dense material changes the timing, so a leather sewing machine may be timed differently than the same one used for upholstery. Then since it takes more pressure to hold down veg-tan leather between stitches, than vinyl or upholstery leather, we sometimes swap out the coil spring over the outside presser foot for one with stronger coils. It is interesting to note that even though your machine has been altered to sew leather efficiently, it will not lose its ability to sew light weight materials. But, you will need to reduce the top tension and use smaller needles. There are other changes that can be made to a flatbed or cylinder arm walking foot machine, to make it more friendly to veg-tan leather, but these are the basics.

Oops! I listed a type 135x15 by accident. It should have read 135x17, which has round point. 135x16 is a leather point of the same type.

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.