Wizcrafts

Almost all modern industrial sewing machine motor pulleys, the machine pulleys, as well as speed reducers, all use 3/8 inch wide v-belts, which are known as type 3L.

The shaft goes through a hole in the frame. Can't recall if it is smooth or threaded. The nut on the back stops it from turning.

Loosen the hex nut on the back of the housing for the bottom disks, then turn the split shaft one way or the other to change the tension on the check spring. Lock the nut down when you are happy with the spring tension.

They are just straight stitch tailoring machines, capable of sewing chaps, pants, zippers and other light weight items. The presser foot typically lifts about 5/16 inch maximum, depending on how thick the foot is top to bottom. Thicker presser feet may only allow 1/4 inch under them to be sewn. The thread handling capacity may max out at either #69 or #92 bonded thread, depending on the condition and configuration of the bobbin case, shuttle race and shuttle driver. Mine maxes out with #69 thread. The machines are good for light density leather at the most. Forget horse tack!

Enough to follow the thread as the take-up lever descends and hold the thread taut in the eye of the needle as it reaches the top layer of the work. I should not overpower the top thread tension disks. I usually set my check springs to have enough spring action to snap back to the top when I pull them all the way to the lower stop position. Sometimes you have to increase the spring tension for heavy threads, then back them off a bit for thinner thread.

Try increasing the swing of the check spring. It holds the thread taut on the downstroke to prevent the thread from getting cut by the needle. If it is set for too little motion the thread can twist under the tip of the needle, just as yours is doing.

Best I can figure, by comparing rulers, is that your range of sewing, in numbers I understand, are from 3/16 to 5/8 inches. This is fully within the normal operating range of the 441 type machines. Examples include those from Cowboy (CB 3500 and 4500), Cobra (Class 3 and Class 4), and Techsew (4100 and 5100). An Adler 205-370 will also handle this range of leathers. All of the above are cylinder arm machines with triple feed, large cylindrical bobbins, massive cases, moving parts and bearings and the ability to sew with thread sizes 92 through 415 (USA designations). If those sizes aren't common in your country (you gave us measurements in metric), consult this thread and needle chart to find equivalents.

Never mix thread sizes on a holster that will be worn by anybody in law enforcement or security work, or on a webbing tow strap, or any horse tack, or heavy dog collar/harness.. Use the strongest thread that allows you to bury the knots inside the layers. Use whatever size needle it takes to get the job done. If absolute strength is not an issue, you can use 1 size smaller in the bobbin. Sometimes the thinner thread lays better on the bottom. It depends on the material. This may allow you to downsize the needle by one number.

Steve; I don't know about any connection between Puritan and Union Lockstitch, other than basic appearance of the casing. All Unions are lockstitch machines, while most Puritans are and have been chain stitchers. Maybe they shared foundry costs way back when... An owner of a ULS is like a horse owner. You must train each other to get along amicably. I have owned and mastered two ULS machines. They are unlike anything else, if you can get along with each other.

Steve. That little yellow book is all there is, aside from YouTube uploads from Campbell-Randall, or private users.

I recommend upgrading to the adjustable height pedestal table setup, as is used on the CB3500 and 4500.

I think I interpreted the two photos in reverse order when I commented. If the knots are indeed visible on the top, increase the bobbin tension.

You need to tighten the top and bottom tensions a bit and maybe increase the throw of the check spring.

The Juki LU-1508N and NH are about as high end as you can get in a standard walking foot class machine. Model N uses the common walking foot system 135x16 needles. The NH uses the longer Pfaff system 190 needles and can actually sew 7/16 inch of material. Normally, these machines top out at 3/8 inch. Both have the double capacity Juki LU bobbins that keep on going and going. Both use commonly available presser feet and bolt on accessories. Should Tom win this machine, he can expect to be happily sewing leather 3/8" thick, with #138 or even #207 on top and #138 in the bobbin (with #23 or #24 leather point needles). Unfortunately, pushing it beyond 3/8" will not yield a good result in most cases. If the machine is sub-model NH, caution will be needed to avoid any deflection of the needle as it enters the layers. In my experience, system 190 needles have very little tolerance to deflection and either bend or break tens times more often than the common system 135x16 needles. The NH class is really designed to sew thick, but soft leather items, webbing and denim garments.

Depending on your competition and the condition of the machine and if you are up against sewing machine dealers, the bidding could go up to $1200. These machines normally sell for about $2500, plus or minus.

I forgot to mention that with #69 thread I use #18 needles. They poke a hole very easily and it doesn't require very much foot pressure to hold the leather down as the needle ascends with the knots.

The 29-4 was an mid-early model in the development of the UF machines and an improvement over the first designs. 100 years ago they were state of the art for what they were built to sew: shoe and boot uppers and thin leather straps and patches on sleeves and knees. The cobblers and saddlers did not have any bonded nylon or polyester thread; just cotton and glazed or hand waxed linen. Over time the design was modified to make the machine more usable for a wider variety of work, eventually including handling of very strong bonded thread. This thread places more stress on the tensioning items, including the take-up lever and check spring. It also is rougher on the shuttle gear, with the increased top tension needed to pull knots up. Advancing the leather with tight bonded nylon stitches is harder than with cotton or linen thread, which has a softer lay. This causes the thread feeding cam and ring to wear down, leading to smaller stitches. Thus, patchers wear out faster when used with modern thread than if one stayed with glazed cotton or linen. The newer models, with replaceable gear boxes and thread slack adjusters on top can have bottom end parts replaced more easily than the old style, which has the rack gears hidden inside the arm. The original needle system for Singer patchers was Singer type 29x3 and 29x4. Those are going out of production now, so most of the working patchers are using system 135x16 instead. The shaft top end fits inside the needle hole and the length to the eye is about the same. But, the 135x16 has a cut-away scarf, where the 29x4 is straight all the way to the eye. A marginally timed 29 machine with system 135 needles may skip stitches more often than the same machine with system 29x4. As for the maximum needle size size the 29-4 can handle, that would be as large a needle as will fit into the needle mount and make it through the large hole in the throat plate. It would need to be moved to the left to avoid making hard contact with the hook. The thread is another matter. You can use any size thread you like, as long as it fits through the eye of the needle. But, will the mechanism be able to pull it up to form a knot inside your leather? In my personal experience, with 5 patchers I've owned, the practical limit is #138 bonded thread on top and #92 in the (tiny) bobbin. While you can use #138 in the bobbin, it won't go very far and requires more top tension and a bigger (#23) needle to get the job done. Bigger needles and heavier thread puts more stress on the presser foot spring, which must then be tightened up to hold the leather down. This adds more work for the feed cam, usually leading to shorter stitches. With the cost of replacement parts being higher through the years, I want my patcher to outlive me. So, I limit it to #92 thread, maximum. Most of the time I use #69, top and bottom. It is easier on the entire mechanism and can be used to sew very thin projects once around and thicker ones twice around. Then, it's time to load another bobbin!

They're polished on a buffer, not plated. Those feet and throat plates are cut from stainless steel. I have modified a couple of mine and buffed them up with green rouge on a medium cloth 6" wheel, on a grinder.

Yes. Go to the CB4500 page and click on the link in the right sidebar to see all available accessories in a pop-up window. There are links to photos in the pop-up window.

Another difference is that the ancient patchers had a torsion bar pressure spring running along the back side of the body, whereas the 29k models switched over some time ago to an internal coil spring, with a screw in adjuster for foot pressure. The old torsion bar had a sliding puck to adjust the amount of lift the foot got, while the newer style has a butterfly screw in a slot, directly on the back side of the head. Furthermore, the newer style has a screw adjuster inside the trapeze on top. That adjuster allows you to control the position of the knots, or to add/subtract slack in the top thread. It can add lift to the take-up lever as the needle ascends The old model 4 only has a thin spring to keep the thread under control as the needle bar moves down. It does not add lift as it ascends. The newer models have a removable gear box, where the -4 does not.

I can see one of those in my future!

As I suggested, contact Bob Kovar. He owns all kinds of sewing machine manuals and parts lists. He probably has one of the largest collection of parts for all model 29 machines in this hemisphere.

I used to have one of those spring foot machines. It was my second industrial sewing machine and I kept it for just two stressful weeks. If I recall correctly, it used the same needle system as the 96k40 I bought first: system DBx1, 16x257, 1738. That machine did very poorly on slick leather, with a limit of #138 thread top and bottom, using a #23 leather point needle. The stitches were all over the place, changing from long to short, as the foot slipped on the slick top grain. I think these machines would be best limited to #92 thread, which doesn't need as much thread tension as 138. The higher the thread tension, the harder it is to advance the work without compound feed.

Contact Bob Kovar, at Toledo Industrial Sewing Machines: 866-362-7397.

Find an upholstery or drapery shop and ask what they use and what they might let go of. Look for a compound (triple) feed walking foot machine made for upholstery work. Bring material and test anything you find. Upholsterers tend to stick to major brands that can be serviced by any industrial sewing machine shop. They avoid cheap Chinese knockoffs, favoring American, German and Japanese built machines.