Wizcrafts

@Agent319Contact Bob Kovar, at Toledo Industrial Sewing Machines, in Ohio, or Ralph's Industrial Sewing Machines in Denver. Both are long time Singer dealers. I believe that Ralph's bought all of the remaining parts when Singer went out of the industrial sewing machines business. Finally, there's Hoffman Brothers in Des Plains, Il. They were also Singer sales and service going waaaaaaay back.

This is very good advice. It might not be obvious to some people who haven't worked on disassembling sewing machines before.

That's a first for me. I have never had a machine that threaded the bobbin retainer tab like that.

First of all, I see thread that is bound onto the bobbin hold down tab. Free that thread before you do anything else! There should never be thread trapped like that! After freeing the thread from the tab, check the hook timing vs the eye of the needle on the upstroke. A properly timed hook will intersect the needle about 1/8 inch above the eye and sill be within the scarf cutout. Many times, a late hook will cause that snapping sound. Advance the hook a bit the loosen the thread loop. The check spring comes into play here. If the travel is too long, the top thread stays taut longer than necessary. Before you change the bottom stopper, try moving the screw in the curved slot to the right end of its travel. If that doesn't help, loosen the screw under the bottom stopper bracket and move it so the spring only moves a little past when the needle makes contact with the top of the leather. This adds slack thread and reduces the tension as the thread goes around the bobbin case.

I agree with your assessment. I got my Cowboy cb4500 in 2011 or 12 and haven't had any mechanical problems or failures yet. It has more than paid for itself over these years. I will mention that it is necessary to keep it well oiled to ensure a long life. This involves removing the left faceplate occasionally to oil all the little holes in the crankshafts.

What kind of motor is it? Can you take a small resolution picture of the machine and the motor under the table and upload it here? Use the lowest setting on the camera, like 1x1 or 3x4. If you need a new motor, consider this type, which I use.

@Lostranger When I have problems with patchers, and the timing is as close as it can be set and the bobbin thread is not getting picked up, I look at the following things. The top threading. Make sure you've gone around the top tension disks and that they apply sufficient tension when the foot is down. Make sure you are feeding it through the hole in the check lever on top, then down the snout. The needle system. Make sure you are using either System 29x3, 29x4, 135x16, or 135x17. Make sure that there isn't a broken needle shaft stuck inside the needle clamp and that the needle is all the way up in it. The needle orientation. Make sure that the rib side is facing left and the scarf cutout is facing due right. The needle position. You can move the needle clamp to the left or right to get as close to the hook as possible. The paddle spring. This often overlooked spring is inside the needle bar, just above the needle clamp. It's job is to hold onto the top thread as the loop is formed when the needle makes a down>up job. If this spring is bent, gouged, or missing the thread loop will dissolve before the hook can pick it off the scarf of the needle. Check the driving gear inside the gear box to see if it has come loose. This gear is directly under the shuttle. There is a small screw inside the gear that secures it to its shaft. There is a hole on the back of the arm, inline with the gear. Rotate the wheel to bring the screw into view in that hole.You'll need a narrow blade precision screwdriver with a flat blade and good side handle to tighten it if it's loose. A loose drive gear throws off the timing. Finally, adjust the spring tension and travel of the check lever on top. It's possible that the spring is pulling it up too much and overpowering the paddle spring as it tries to secure the loop at pick-off time. If all of this fails, get rid of it. I fought with a blue body Singer long arm patcher for years and it never sewed reliably. I got rid of it and bought an Adler 30-7 and haven't looked back.

Good find! Now, have you figured out how to keep this from happening again?

There is a screw going into the housing that holds the check spring shaft in place. You should see it on the right side behind your arrow. Loosen it and wiggle the shaft out. The screw's job is not just to hold the assembly in place. It also is used to adjust the spring force. You would loosen that set screw, then rotate, then use a screwdriver blade to rotate the shaft to the left or right for more or less force. Once you are happy with the spring setting, lock the shaft down with the set screw.

I'd start feeling and looking at the thread guides for burrs. You didn't mention whether or not the thread is bonded. If it isn't, you're supposed to run it through the wax pot to bond the strands. If you don't have Sellari's stitching wax, order some online.

It is not difficult to add a speed reducer later. However, you will need to buy two new V belts: one from the motor the the large pulley on the reducer, and the other from the reducer's small pulley to the machine's pulley.

@JWfur If you intend to use a 441 clone to sew thin or soft materials using thin needles and thread, you'll probably need to upgrade the stock feed dog and throat plate to a narrower set that resists the tendency of some materials to get shoved down into the cutout in the throat plate and the oval hole in the feed dog. These aftermarket feet and throat plates are made by one of our members. His website is here. I use some of his items.

I use the servo motor and speed reducers listed on this web page.

Sailrite does offer smooth and a knurled foot set for their leather sewing machine variant. The pebble grain pattern is a little friendlier to veg-tan ;leather than the stock feet, which have angled teeth. The totally smooth set will have less pull on the top layer and could slip instead of feeding slick material.

The 5100 can sew fur items if you install the blanket foot set made for it. This set has teeth on the feet and feed dog that help grab slippery material.

The O.P. hasn't responded since he posted this, on April 14, 2024. I suggest that you start your own topic. If you upload photos, keep them as small as possible and in .jpg format.

@Pinto, sometimes the only way to obtain replacement parts that aren't available from dealers is to buy another machine of the same make and model and salvage parts from it. In your case, you could hunt for another Singer 15-91 in antiques shops, or Craigslist. Or, buy one from Ebay and pay through the nose.

I have used Barge TF with good success. But, lately I've been using Master Cement and it is a permanent bond. Master is usually sold to shoe repair shops, which is how I learned about it.

I've seen these fake Techsew 5100 machines advertised on Facebook and reported them as fraudulent.

Man, that machine must be a dragster with 16 cylinders! This is a scam post, hosted on an uncaring Alibaba store. Chinese resellers have been ripping off the Techsew brand name tags in photos they steal from the Techsew website for a couple of years now. They especially like to pretend to sell the model 5100 for beer money. Some unsuspecting schmuck actually gets fooled in to sending them the $600, only to start getting shipping, customs, export fees, and warehousing bills that quintuple the price in no time. One of our Australian members went through that a couple of years ago.

Yes, absolutely! Patchers are totally top driven by the teeth on the bottom of the presser foot. You must apply enough foot pressure to move the material and not let it lift as the needle ascends. The teeth will leave tracks in veg-tan leather, Latigo, bridle leather and some other retanned leathers. It doesn't usually leave marks in chrome-tan leathers. If you grind down the teeth, the foot may just glide over the leather. Some have had success shrinking carburetor air tubing over the legs of the foot.But, with the reduced top drive, you may need to push or pull the work to get acceptable stitch lengths.

I hate to have to tell you this, but Guest accounts cannot use our messenger or email systems. You will have to join LW.N to use them. Otherwise, you'll have to leave some other method of contacting you. Do you have a website with a contact form? How about a throwaway email address created for this occasion? Recent Firefox browsers let you create use and lose free email accounts. The details about Firefox email Relay accounts are outlined on this page.

@LomaeArts If it's a real Singer twin needle machine, it will have two hooks; one on each side under the cover plates. I believe that it would then be a model 112 or 212 (G or W) - (number). See this post for pictures and details about the Singer 112/212 twin needle machine.

@waynebergman When buying your first leather machine, buy a complete working machine that has everything intact. If you have trouble finding information about a particular make and model, move along until something well known comes up.

The difference is I WANT that 360 post machine! LOL Actually, the big difference would be that the post machine "bed" moves as you turn the work, thus, not fighting the operator. A patcher is fine if you have a defined entry point and can sew circles without running out of room for the arm. With a rotating bed, if the work fits over the little post, it gets sewn without a fight. As for the feed, the post machine appears to have a roller foot. We don't know if it has a driven foot, or feed dog, or if they are passive. If the rollers are driven and in sync, the feed would be very positive. The patchers are all top driven only via the teeth on the presser foot. No teeth, no feed. Patchers tend to get hung up on bulges or new layers on the bottom. Roller foot and walking foot machines usually have no trouble with new layers and small wrinkles on the bottom.