Wizcrafts

It could be the thread having too much coil action off the spool. The twists and turns from twisty thread cause tension changes and possibly even skipped stitches. This is especially likely if the thread loop twists away from the hook on the upstroke. Sometimes it helps to wind the top thread once around the top post in the opposite direction to the natural twist of the thread.

There is an image on the lower left of the CB4500 page with a photo copy of their ad from Shop Talk magazine. Click on it to see a larger readable view. Turn off your ad blocker if you don't see it. Sometimes, just refreshing the page will get it to reload and display.

Joe; You asked about "stitch by stitch sewing" I can do that with any motor I have, including clutch motors. You have to treat the foot pedal like you are driving a Beetle or Fiat, or some other small clutch operated car. You slowly move the toe down until you feel the motor start to engage. There is an adjustment bolt on the right end of these motors that lets you adjust the free play before the clutch engages. All clutch motors accept a standard inside diameter (usually 20mm) type 3L, v-belt pulley. Type 3L v-belts are 3/8 inch, or 10mm across the top and are the standard for the industrial sewing machine industry. These pulleys are made in outside diameters ranging from about 40mm, up. I have found that I can feather one with a 70mm pulley as well as one with a 50mm, down to 1 stitch per second. The difference is in the top end. The 70mm lets you sew about 50% faster with the pedal down. If you buy a servo motor after the machine, it may need some special linkages or changes to where the linkage bracket is connected to the floor pedal, to line it up under the control arm. Most servo motors have the control arm facing forward, towards the operator. All clutch motors have the leever under the motor, facing sideways and connecting on the left end, via a ball joint, straight down to the pedal.

Joe; I would go with the Juki and learn to feather the clutch first. If you have trouble controlling it, change the motor pulley to one that is 50mm or 70mm in diameter. This will slow down the machine at all times and may not let you get long runs done as quickly as normal upholstery machines. If you charge by the hour, faster is better (in upholstery). The Juki is capable of sewing quite fast, when needed. If you find you have a hard time controlling the slower speeds on the clutch motor, look into getting a servo motor. Try to find one with your available voltage and connection, which is rated at 1/2 horse power or better and has a rotary knob to limit the top speed. I have three motors like that, two of which are the Family Sew model FS-550s. I don't know if that motor is available in 220 volts or not, but others probably are. It is even possible that the same company ships a different brand name of the same motor to European customers. The advantage of this type of motor is that you can just twist the knob to slow it down to about 2 stitches per second flat out. Twist the other way and it will drive the walking foot machine as fast as it can go. You get slow speed accuracy, plus high speed money making capabilities, all in one motor.

Thank you Uwe for that research.

I have a little side business refurbishing and selling old iron Singer sewing machines. The oldest one in the rack right now is a model 27, from 1902. I cleaned, oiled and lubed it, then adjusted the clearance of the bullet shuttle. That 114 year old machine sews 2 layers of 4-5 ounce leather, denim jeans and just about anything I can fit under the foot, with #69 bonded nylon thread. The Sphinx decals are in good condition. It amazes me that nobody has expressed the slightest interest in buying the machine. Quite frankly, I don't care. I know I can cart it into my shop (15 feet away) and sew with it in one minute or less. It does one thing and does it well. It sews tight, straight stitches, up to 5 to the inch. One hundred fourteen years and still going strong. It thrives on oil, clear grease and fair treatment. With more of the same, I expect that it will be capable of continuing on its timeless journey for another hundred years. Treat your Cowboy machine with the same respect and it will outlive you.

On Tuesday, Jan 19, I used my Cowboy CB4500 to sew two unusual jobs for this type of machine. The first one was sewing new Santa Claus type uppers into a leather shoe. The second was sewing a new leather liner into a felt Cowboy hat I am refurbishing for a customer. I used #138 Cowboy brand bonded nylon thread, with a Schmetz #23 leather point needle. In the first case, the length of the arm and positive triple feed made the job much more efficient than if I'd done it on a patcher. In the second case, there is enough clearance on the right inside of the head to clear a 4 inch hat brim. Using a left toe foot I was able to sew the liner into the hat directly over the original stitch line, which is where the crown bends into the brim. My drop down edge guide was adjusted to clear the folded out lamb skin liner and still keep the brim from moving too much as I rotated the hat. Normally, hats are sewn on roller foot post machines. But, I don't have a post machine at this time. That needs to be remedied real soon.

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.