Wizcrafts

I agree with your thread size choices. Always use a thread size (or combination) that allows you to bury the lockstitch knots well inside the layers. Needle size can affect the position of the knots considerably. If the needle is the minimum size for the top thread, the knots will be harder to pull into the bottom. Go too big and the knots may appear on top. So, what kind of sewing machine are you using for these bags?

Chuck; I'll try to give you a better understanding by describing typical uses of the various sizes of thread (in leather work). First of all, the thread uses in leather sewing machines is usually bonded nylon or polyester. Harness stitchers can also use linen thread that is run through a wax pot. The bonded threads are referred to as numbers, or a letter-number, such as #69 or T70 (equivalents). Linen thread is rated by the number of cords that are twisted together and glazed in place (e.g. 4 cord). The sewing thread used for leather increases in diameter and strength as its number increases. If we use #69 = 1 (11 pounds test) as the baseline, #92 = 1.5x, #138 = 2x, #207 = 3x, #277 = 4x and #346 = 5x. The threads uses for hand sewing leather are normally rated by the number of cords that are twisted and waxed together. They seem to average a range of between 4 and 7 cords. Four cords would be about the same diameter as a #207 or 277 bonded thread, but would have much less breaking strength. Linen, cotton, or hemp cord is not typically as strong as nylon or polyester of the same diameter. A holster that one would hand sew with 6 cord waxed linen thread could be sewn with #277 bonded nylon and be just as strongly secured, per stitch. However, the 6 cord thread would actually be thicker and look more impressive to the eye. If you are at all familiar with the thread that is used to sew a normal dress shirt, think of it as about the equivalent of a bonded #33 or even a #46. Think about the thread that is used to top stitch your jeans and it will fall around the same thickness as our bonded #69 or bonded #92. Leather garments are usually sewn with thread sizes ranging from #69 to #138. The #138 is used to hold thicker seams together. It has 22 pounds of test per stitch. Zippers are usually sewn with #69 or #92, so look at the outside zippers on a leather jacket for a reference. Upholstery shops normally use a lot of #69 bonded nylon, unless extra strength (or extra thickness) is needed. Then, they'll switch to a machine loaded with #138 bonded nylon. Marine upholstery sewers avoid nylon where the material is exposed to the Sun and outside elements. Instead, they sew with bonded polyester thread, which is a lot more expensive, but isn't as affected by UV rays or wild temperature swings. Might I ask what you want to sew? I can recommend the best range of thread sizes and types based on your expectations and type/model of your sewing machine. Some sewing machines cannot handle anything larger than #69 bonded thread. Others can go up to #138, or even #207. The big machines that we refer to as 441 clones are able to sew with very heavy bonded thread, all the way up to #415. That is about the same size as the linen thread used to sew leather soles onto boots.

Here is a thread size vs needle size chart. The diameter of each size thread is listed in the right-most column.

The Singer 153 uses a standard industrial G bobbin. It holds a modicum of thread, as long as it is not too thick. I used to own that model and found that it was best used with #69 or #92 thread. Sometimes I would use #138 as a top stitch thread, with #92 in the bobbin. This is a very old machine.

Yes, it is true.

Fair to Midland, depending on how straight the edge is and how thick it is. The spring guides work best when the edge is dead-straight and at least 1/8 inch thick. If the leather is much thinner, or the top is rounded, the guide can slip over the edge.

Unless my eyes deceived me, I did not see you hold back the threads as you started to sew the test strip of leather. You must hold back at least the top thread, if not both. Failure to hold back the thread causes too much top thread to get pulled underneath and it bunches up under the leather and sometimes around the shuttle race. When the thread bunches up under the leather, the teeth can't move it against the tension of the bunched up threads.

The only hope that you will have with a machine like that is to change the foot to a full roller equipped foot. You will lose about 1/8 inch of the available clearance because of the thickness of these feet, compared to a standard flat foot. You will also need to purchase #18 leather point needles and #69 bonded nylon, or bonded polyester thread. That is as thick a thread as these machines can handle. The foot pressure will probably need to be cranked most of the way down, to keep the leather from lifting with the needle. The density, slipperiness, and combined thickness of your leather will determine what changes will be required to sew it properly.

Don't bother trying to sew 2 ounces on a 441 (Juki TSC 441) or clone (Cobra, Cowboy, Bogel, Techsew, etc). Get a separate machine for your wallets and zippers. Any flat bed walking foot machine will do. They will also sew up to 3/8 inch of leather, with #138 thread and sometimes #207. The 441 type harness stitchers have a practical lower limit of about 6 ounces, with #92 or 138 bonded thread. Most are made for very heavy thread and will have trouble sewing with #92 and under. You might get it to sew forward, but it may skip in reverse. Sometimes thin top thread gets jammed inside the shuttle race. These machines are best suited for use with size 207 and larger thread and leather thicknesses of 1/8 to 3/4 inches, However, if you are careful and make the required adjustments, they will sew from 6 ounces to 7/8 inches. If you sew a lot of items that have vertical shapes or curves, a cylinder arm is the best machine.

Edge guides are devices that mount onto a sewing machine, either on the bed (screw on and slide to use), over the front side (clamps between front side of machine and cutout in table. Swings away or inline with needle.), or on the back of the head (drop down style). No matter how they are installed, all of them have a means of moving a roller or flat plate towards or away from the plane of the needle. You loosen an adjuster to set the desired distance between the left side of the guide and the needle, then lock it in place. As you sew, keep the material pressed against the guide and you will get a perfectly straight stitch line. Any industrial sewing machine dealer has edge guides. You can buy them in various configurations for whatever your machine requires. Toledo Industrial Sewing Machines, a supporter of this forum, sells them. I strongly suspect that all of our contributing and supporting dealers have any type of guide you may need. Some dealers will even create a custom edge guide for your requirements.

Send me your Puritan OSXL Darren!

I always use an edge guide when sewing anything along an outside edge.

Cheryl; I bought a so-called walking foot attachment for my 15-91. All it does is allow the top layer to move at the same rate of speed as the bottom feed. There is no drive on top. They are spring loaded to snap forward when the feeder drops below the throat plate. In reality, these devices are even-feed attachments. You will lose about 1/8 inch of available thickness that can be sewn, to allow for the height of the alternating feet. So, if you were able to sew 1/4 inch, you will end up at about 1/8 inch, or so, with the attachment.

I used to braze new bronze points onto the hooks for my first Union Lockstitch machine, then file them into custom shapes. I finished them with a couple grades of Emory cloth, then buffed on a buffing wheel with brown or green compound (I forget which).

Your photo is blurry, so I can't see the details on your needle. Make sure that the ribbed side faces due-left and the cut-out scarf faces due-right. Watch the needle as it goes down and ascends. After rising between 1/8 and 3/16 inch, the hook should meet the scarf, about 1/8" above the eye, with the direction/feed lever in the zero position (Trox has posted the exact dimensions in metric. Search this forum). Then check in the full reverse position to see if the hook is still above the eye. Marginally timed machines may sew fine in forward, but allow the hook to clip the thread at the top of the eye in reverse. It happens to me sometimes and I reset the timing on the needle bar. Even solidly secured needle bars can move up due to the extreme shock they endure when sewing hard leather. This throws the timing off. Another thing to check for is the lateral clearance between the hook and the needle. Some big Adler machines use a little numbered spacer with two screw holes to place the needle the best distance from the needle, for a given size needle (default is #200). If your needle is a #200, but the spacer is the wrong number, say a #180 or #160, contact will be made between the hook and needle. GottaKnow Eric has given good advice in his replies to remove the throat plate and watch the loop form and see what actually happens when the hook meets it. If the loop disappears, reduce the travel of the check spring. If it twists forward or backward, consider using a different spool of thread. If the loop is way too small to be picked up, try going down one needle size. Another thing is the type of thread you are using. Poly-cotton is really made to be used in heavy duty domestic or quilting machines, as a top stitch thread. It is very soft, compared to bonded nylon or bonded polyester that leather workers normally use. These machines are capable of treating cotton thread with kid gloves. Your big Adler is not built to pussy foot around with soft thread. Also, your thread may have been wound with a right hand twist, which is the opposite of what your machine requires. Harness shops often use needle and awl stitchers that sew with glazed, left twist, linen thread, run through a liquid wax of some kind. The wax adds body and lubrication to the thread as you are sewing, then hardens to secure the stitches in place. Linen and cotton thread are related!

It depends on what size thread you want to use to secure your 1/4 inch thick belts. If you don't need to exceed #138 thread, a normal industrial walking foot machine, like a Consew 206RB-5 will do. Slow it down with a 2.25" motor pulley, or get a servo motor. You'll want to get some #23 leather point needles for the job.

Is the needle bent? Is it inserted correctly in the needle bar mounting hole? Bunched up thread under the cloth usually results from either too much bobbin tension, or too little top tension, maybe caused by incorrectly threading the machine on top. Are you feeding the thread through the check spring, then up and down from the take-up lever? If I recall, these machines may be belt driven. If the belt has stretched, your timing will be out. Are you trying to sew cloth, or leather? This is not a leather sewing machine.

Does Ceroxylon gum up the tensioners, guides, or needle's eye? Is it water soluble if it thickens in the pot?

Maybe this Adler burned at Fahrenheit 451, the temperature at which insurance claim paper ignites. Montag!

Which machines do you use Ceroxylon with?

Try using liquid silicon lube, which is sold in quart bottles by most industrial sewing machine dealers.

Nope

No. Only the zipper and edge tape feet normally have teeth on the bottom. The rest are usually smooth. Walking foot machines we use in leather work usually have triple feed, where the needle, inside foot and feed dog move in synchronization, as the outside foot raises and lowers to allow feeding motion or stop it. There is no need for rollers on w.f. machines.

Look at some of the type 227 cylinder arm machines. They are usually medium duty walking foot machines with about a 3" diameter arm. They take the same presser feet as most standard walking foot machines made by Singer, Juki, Consew, Chandler, etc. Capacity is typically 3/8 inch, using #138 thread.

Precisely! I have two of them with different useful spacings. Roller feet are for straight stitch, single foot machines only, not walking foot machines. They allow the top layer to feed smoothly, without dragging on the bottom of the presser foot.