Wizcrafts

There's a third and fourth possibility. 3: The thread is too well bonded onto the spool in some places but not others. As you sew the tension changes as the thread leaves the spool. 4: There is a starting thread stub sticking out of the bobbin that interferes with the smooth flow of thread off the bobbin.

That machine is a non-feeding bag closer, or freehand pattern stitcher/tacker.

I forgot to address the term "cobbler" machine. Cobblers, or shoe repair persons, fix or build shoes. One of the machines that are found in shoe repair shops is a boot patcher. It is a free arm machine with a special top feed foot that can pull the work in any direction. Their very slender arms allow you to sew well into a shoe or boot, before it bottoms out. Despite their impressive appearance, patchers are only meant to sew shoe uppers, or to sew patches onto garments. I use mine to repair handbags, sew over loose or broken threads in shoes and boots, apply embroidered patches to Bikers' vest and jackets, or to sew small objects with thinner thread than my other machines use. Most patchers can only sew up to 1/4 inch of leather. The maximum stitch length of a brand new pristine patcher is usually only 5 stitches per inch, into about 8 ounces of leather. The stitch length diminishes at 1/4 inch. Worn out patchers are known to lose their maximum stitch length to as little as 8 per inch. And again, they work best, last longer and sew the longest distance between bobbin changes using #69 bonded nylon thread.

tag302; It would really be a big help if you told us the brand name and model of the "cobbler" machine you bought. A picture is even better. However, being the fool I am, I will venture a guess and offer some suggestions. I guess you bought some kind of "patcher" machine. If so, since it came with a #18 needle, it is probably made to sew with #69 (T70) bonded nylon thread. This is one of the most common upholstery grade threads sold to both hobbyists and professional sewers alike. Number 69 bonded thread is available in nylon and polyester. It is made of three strands of smaller mono-filament thread that are twisted tightly together and coated with a bonding agent, then wound onto large spools. This triples the strength and gives it a breaking strength of 11 pounds test. This thread is usually sold as cone shaped spools, ranging from 4 ounces to 16 ounces per spool. Since I am guessing about the nature of your machine, I can't assume to know its upper thread handling capability. But, as the owner of two Singer patchers, one with a small bobbin and one with a large bobbin, the largest size thread they handle well and reliably is #92 (T90), which is 15 pounds test. I use either a #19 or #20 leather point needle with #92 thread.

The topic you responded to is from November 2014. The manual was sold on eBay in Germany and is long expired. Your only hope is to post in our MarketPlace Items Wanted ads for the manual. Or, maybe somebody who is currently on the form has a manual they can photocopy and digitize or mail to you. If anybody has an e-manual for a Singer 133k4, please contact new member Raymond Okini.

That machine is a very good garment sewing machine. It can sew very fast, as long as the oil wicks haven't hardened up. You should be able to run it at about 4000 stitches per minute, or 66 per second. It will definitely get the job done is a short time. It uses the standard straight stitch system 16x257 needles. According to the old Consew info page, it is: "Suitable for stitching such products as blouses, shirts, men's, ladies, and children's apparel, lingerie, dresses, sportswear, work uniforms, jackets and coats"

Hmmm. Let's see. I've sewn lots of leather projects that are 8 or 9 mm thick, with multiple layers and gotten great stitches. I'm curious if you are referring to the top, bottom, or both sides? If top, the geometry of the needle has a lot to do with the appearance of the top stitches. Some leather point needles produce a straight line of stitches. Others produce slants to the left or right. Simply changing to a different type of leather point can change that stitch line's appearance or lay. Using a regular round/sharp point needle in leather can have disastrous effects. Too large of a needle make a hole that is too loose to secure the knots inside the layers. Too small and the knots are hard to pull up and will be visible on the bottom. If the correct size and shape of needle is being used, but the knots are visible on the top or bottom, there is a fault either in the top or bottom tension adjustments, the thread itself, the top thread path to the needle, or the way the bobbin is wound. Knots that are consistently on the top indicate that either the needle is much too big, or the overall top tension is much too tight, or that the bobbin thread is not feeding under the bobbin tension spring, or that is under the spring but the tension screw has backed off to zero bobbin tension. If the knots lay on the bottom, either the needle is too small, the top tension is too loose, or the bobbin spring is too tight, or a combination of the above. Knots that move up and down indicate an intermittent change in tension. This can be caused by top thread that was over-dyed, or double dyed and comes off the spool like a coil spring. Try wrapping it around a post on top of the machine in the opposite direction of its natural coil. It can also be caused by foreign material caught inside the tension disks or thread guides, or even a bad needle that is gummed up or nicked. Sometimes, when you finish winding a bobbin and cutting off the starting thread, you may have a thread stub sticking out of the starting hole. That thread stub can drag once per cycle on an anti-backlash spring, or on the inside of the shuttle. Make sure you snip the bobbin thread stubs clean off right at the metal hole it comes out of. Another often overlooked cause of bad knot placement is the check spring. Its job is to maintain tension on the top thread as the take-up lever moves down. It's supposed to hold it taut until the tip of the needle meets the top of the material. The purpose it to prevent the needle from splitting loose top thread as it hits the material. If the throw of the check spring is too long or short, the stitch placement can be affected. If it has too little tension it won't do a good job of following the thread. It it's too tight, the thread may go into the material with too much tension on top. This could cause little puckers on top, or drag the knots higher up that you expect. Finally, machines that can't produce a decent and consistent stitch and knot placement may be operating beyond their current capabilities. It could be a misadjustment, wear in the take-up or bobbin area, or the thread is too tough or wide to be tensioned smoothly. So, what size needle and thread have you or your dealers tried to use that failed in those machines? A light duty walking foot machine may have been originally setup to be optimized for #69 bonded nylon, using a #18 needle. It may not work well with #138 thread and a #23 needle. In fact, it may hit the needle head on or deflect it into the feed dog block instead of passing close to it in the scarf above the eye. You may need a heavier duty class of machine if the standard upholstery machines can't sew your leather to your satisfaction. There are flat bed machines made to sew with heavier thread sizes and bigger needles than upholstery machines. Everything is beefed up on these beasts. They are to standard walking foot machines what those machines are to domestic sewing machines. Maybe you need to look into a Juki LU-1508NH. Or, check out the extra heavy duty flatbed machines based on the Juki 441 or Adler 205 mechanisms. Better yet, read the specs on the Cowboy CB3200 that is set up and sold by Toledo Industrial Sewing Machines. It might be your huckleberry.

Any triple feed walking foot machine will sew leather up to 9 or 10 millimeters. There will be differences in the thread handling capacities of the different styles and sizes of hooks and shuttles. But, almost every one of these upholstery grade machines will sew up to #138 bonded nylon/polyester thread. Some have bigger bobbins than others. Some may have extra clearance in the hook to pass #207 thread, but most can't. If the machines you are looking at are used, make sure you check them out in person and see them sewing your sample pieces of leather. If you're buying new, get a parts warranty on the machine and a guarantee of technical phone or email support from the seller. There is another matter to consider and that is the cost of parts for the respective brands. Adler and Pfaff replacement parts, if needed, can be very expensive. Juki and Consew parts are less costly, in the overall scheme of things.

Anybody contemplating purchasing a new Consew or Juki, or any other brand of industrial sewing machine for leather, should strongly consider buying it from one of our member/contributing dealers who have a vested interest in this forum. These guys will support you after the sale and assist with timing and operational problems you may experience. I count Gregg at Keystone as one of these contributing members. He, along with "Cowboy" Bob Kovar, "Cobra" Steve Tayrien, "Techsew" Ron and "Able" Darren Brosowski stand behind what they sell. Sure, you may find slightly better prices on eBay, but not the pre-sale advice and after-sale support many first time industrial sewing machines owners often need. If anybody is curious where the money comes from to keep this forum's server up and running, look no further than the banner ads on the top of every page.

I think you would be better off starting with the SPK3 add-on foot. All you have to do is unscrew the foot that's on now and screw that one on instead. The roller foot conversion involves removing and replacing three items and adjusting the height of the presser bar. As for wheel diameters, each user has to determine that for themselves, based on previous experience.

Here you go: Roller foot conversion kit on eBay Presser foot with rollers on eBay

I have a roller foot conversion kit for my 31-15. It works extremely well as long as any seams are not too much higher than the other layers. The roller lets the leather flow, rather than drag. I also have a 1/2" wide roller equipped screw-on foot that works okay. It pivots at the back to let it climb and roll over seams. My take is that if you need maximum visibility of where the needle is going, get a roller foot conversion kit. If you can follow a stitch line by looking down the middle of a 1/2 inch wide presser foot, get one with rollers on the bottom.

The length can be adjusted by lowering or raising the presser bar. The width being off means you need to either file down a replacement foot that is too narrow, or add a shim if it is too wide.

Holy Mackerel! I have never seen that type of stitch length changer before.

I was finally able to see a picture of a 236G124. It is a roller foot post machine. Singer made these machines to sew patterns onto shoe and boot uppers. They have preset gear ratios that set the stitch length at somewhere between 12 and 32 stitches per inch. The needle system is quite short and is best used with very thin thread. The thread size the bobbin and shuttle can deal with might max out at #69 bonded thread and that requires at least a #16 needle. Depending on the preset stitch length, this needle and thread may or may not filigree the leather. A more likely safe combination would be #46 thread with a #10 needle. This would lay down a nice dash pattern on boots when sewn at about 16 to 20 stitches per inch. Are you looking for such a machine? If so, the price is good, as long as it is in good working condition. There is one for sale in my town for $350. I was interested until I learned about the fixed stitch length situation.

Ken; Can you post a close up photo of your presser bar, showing how the presser foot mounts to it? Hold a small ruler or tape measure along side it. It might help us determine if a harness foot for the cowboy and cobra machines will fit it.

Alex; Did you set the timing at the zero motion position? Doing so will time the needle and hook in both directions. Also, make sure the hook is about 2mm or so above the eye on the upstroke.

I also prefer lubricated thread. Cowboy makes lubed thread. Weaver Leather sells a heavily lubricated bonded thread that has so much lube that it drips all over the machine guides and tension disks. You can buy a magnetic lube jar from various industrial sewing machine dealers. It sits on top of your machine and the thread passes down and back up, through whatever you fill it with. Liquid sewing machine silicon works best and won't discolor fabrics. I get mine from Toledo Industrial, in quarts. I think they may also sell the magnetic lube jars.

My sewing machines in the shop prefer to listen to KWKZ FM on the Internet. They play classic country and new traditional country music that doesn't get national airplay by the bubblegum networks, like Cumulus. A few drops of oil, plus bright lights and country music has those machines singing their own song!

Curved needle Landis machines often prefer soft rock, or soft Country Music. Speak softly when you talk to her. She is a good dancer, so don't try to lead. Just hold the shoe sole bottom side up and say words. Everything you need to know can be learned here, on this video.

I owned a Juki LU-563 and it was only good up to 3/8 inch. It fought me when I tried running #207 thread in it. The LU-1508NH is much more modern and better for higher lift work. I should warn you that those system 190 needles are very easy to bend and break if they get deflected. I found it best to use larger sizes, like 20 through 24, rather than #16 through #19. Of course, if deflection isn't happening, the thinner needles will work fine with #69 and #92 thread. As for clones, I believe that Toledo Industrial now has a 1508 clone. You'll have to ask them which sub-class it clones. I can tell you from experience that the crank shaft opening on the back of the head needs to be altered to allow for higher foot lift with those longer needles. I modified a walking foot machine I had to do that and had to file away quite a bit of metal. Without that alteration, the cranks hit the head and stopped cold. I would ask for a demonstration of a machine sewing at 1/2 inch with system 190 needles before buying it sight unseen. Truth be told, I think that 7/16" is more realistic for both the 1508NH and its clones. If you want to sew with #207 thread, at 1/2 inch, there are better machines that are built with this in mind. My CB4500 sews from about 6 ounces up to 7/8 inch, using thread sizes 92 through 415. I find that #207 is the sweet spot for medium thickness work and webbing. There is even a flat table attachment I got with the machine for times when a table surface is better than a free arm. The Cobra Class 4 is a similar machine and in the same State. If it is too much money, the Cowboy CB3200 sews up to 1/2 inch and is built for heavy thread. The CB3500 sews all the way up to 7/8 inch, as does the Cobra Class 3. All these are less expensive that the longer arm big brothers. You should consider the 441 class from the get-go if you intend to use #207 thread at 1/2 inch. Yes, a 1508NH can sew that high, with that thread, but you will be at its upper limit.

Jeff; The Juki LU-1508N uses the standard system 135x16 (leather) needles and can sew about 3/8 of an inch of compressed material with #138 thread. The LU-1508NH uses a longer Pfaff needle system: 190. These needles are about 3/16 inch longer than standard walking foot needles. Since the shuttle hook is still in the same vertical plane, the needle bar is raised up the 3/16" to keep the needle's eye in time. This also allows the presser feet to raise and alternate higher before they contact the bottom of the needle bar. The difference is that the class NH can sew between 7/16 and 1/2 inch of material. Also, changes to the shuttle allow it to carry #207 thread in the bobbin as well as on top. The list price is somewhere in the mid 3k range. As for heavy duty cylinder arm walking foot machines, I use the Cowboy CB4500, which has a 16 1/2 inch arm, uses up to #415 bonded thread and sews up to 7/8 inch of leather. It comes on a pedestal table with a powerful servo motor and a 3:1 speed reducer. It can sew extremely slowly (well under 1 per second), up to maybe 5 stitches per second, flat out.

The #18/110 needle must make a hole with just a little too much clearance for the lockstitch knots to settle into a happy place. The smaller hole made by a #16 needle makes for tighter knots that are easier to place. What causes this variance? The entire upper thread path affects the repeat-ability of knot placement in leather (or any material). If the thread uncoils differently every other turn, the upper tension changes. If the thread moves up inside the tension disks, there is a variation. If the speed changes in a jerky fashion, the knots will move. The bobbin can also affect the position of the knots. A stub of thread left sticking out the hole in the bobbin might rub against something once per revolution, or the thread may unwind unevenly, throwing off your knots. Try to figure out what is changing most often and see if it can be remedied.

I hear the train a comin', it's comin' around the bend....

I get all that with my Cowboy CB4500, which I bought from Toledo Industrial Sewing Machines. This machine can sew over 3/4 inches of hard leather, with up to #415 thread. I don't normally use anything bigger than #277, or, once in a while, #346 thread, as 44 or 66 pounds tensile strength per stitch seems to be enough for my projects. Similar machines are the Cobra Class 4 and Techsew 5100. If the CB4500 is too dear, look into its little brother, the Cowboy CB3200, also sold and serviced by Toledo Industrial Sewing Machines. It costs much less and only sews 1/2 inch. But, it uses the same bobbins, needles and thread as the bigger machine. These machines are part of a special class we call the 441 clones. They are based on a Juki TSC-441, which was first introduced in the late 1980s. That machine is still in production and sells for about $6,000 US. In contrast, you can buy two brand new Cowboy, Cobra, or Techsew 441 clones for less money than that one Juki.