Wizcrafts

I feed the thread down, through the steel loop guide over the bottom disks, then around the disks twice, then back up through the guide, then to the thread check spring, etc.

I guess a 1/8 inch left or right side edge guide foot set would be nice.

Absolutely! Right now, it is converted into a roller foot machine. But, with a few minutes of screwdriver turning, it reverts to a normal presser foot/feed dog machine.

I'm currently using two turns around the bottom disks.

Those spring guide feet are available in right side, left side and varying distances from the needle. They are very useful for times when a swing-away edge guide won't work. There is also a foot with a spring or piece of steel guide on the front center. It is used to install blind zippers. As far as I know, they are only available for straight stitch machines, not walking foot.

Less bottom tension, more top tension, or a larger needle size.

I wonder how a Hiroshe hook and a Juki take-up lever would hold up with Kevlar thread.

What make and model is the machine?

I am pretty certain that your Landis sole stitcher requires right twist thread. This is the opposite of what modern leather sewing machines use. I would use either 6 or 7 cord, Barbour's Irish Linen thread, which you can buy from the Campbell-Bosworth company. The ancient Singer 29-4 can sew with up to 3 cord linen, or #69 to #92 bonded nylon or polyester thread. I use #69 nylon for motorcycle vest patches and #92 for zippers.

Have a new outer presser foot made with the design on the bottom outside edge. It should emboss that pattern as you sew. You would need a lot of foot pressure and probably wet leather edges to do this.

My CB4500 came with the accessories package that includes a flat slotted throat plate. I removed the feed dog and installed the flat plate. I have to compensate for the changes in stitch length, using the stitch length lever. I find that it is more difficult to get the reverse stitches to hit the same holes as before, so I feather the stitch lever a bit to compensate. I also found that the higher the pressure on the feet, the smaller the stitches tend to become. Reducing the bobbin thread tension helps a bit, by reducing the bottom drag. I think it would be really nice if somebody could make and market a Teflon throat plate with a narrow slot. I must confirm that the bottom looks much nicer without the humongous feed dog that shipped with the machine and all other 441 clones I have seen. The results are very close to my Union Lockstitch machine, which has needle feed, a jumping foot and a narrow slotted throat plate. Unfortunately, I am not aware of any sewing machine dealer who has a narrow feed dog and matching throat plate, or Teflon slotted throat plate available for a Juki 441 or clone. I think that if a dealer on this forum was able to get these parts made, he could sell a shit load of them here.

Make sure you are using the best size needle for the thread on top and bottom. This would be a #25 leather point for #277 thread, or a #24 with 277 on top and 207 in the bobbin. Make sure the thread pulls without binding, especially in the bobbin. Next, back off the pressure on the foot until the adjuster pops out. Test the presser bar to ensure that it moves up and down freely. Then screw the adjuster back on just enough to stay in its threaded hole. Try sewing a stitch or two. If the leather lifts with the needle, add more pressure. Do this until the leather no longer lifts with the needle. Make sure there is no corrosion, dye or oil on the bottom of the presser feet. The feed dog should only protrude about 1mm above the top of the slot in the throat plate. If there are still deep marks on top, check for sharp edges on the outer foot. If you have to screw the adjuster all the way down, you may be sewing into rawhide inside the leather.

I believe I once had a Singer post machine just like yours and I think it used system DBx1 (1738) needles.

Before anybody buys a sewing machine thinking it will sew up to 1/2 inch, see what needle system and thickness of presser feet it uses. If it uses system 190 (Pfaff needles, the (inside) foot would probably have to be less than 1/8 inch thick, with the alternating foot lift set to minimum. Or else, you would have to remove the thread guide from the bottom of the needle bar. A machine equipped with the regular system 135x16 needles will not sew 1/2 inch, unless you remove the feet. You don't really get into a 1/2 inch capable machine unless it uses systems 214 (328) or 794 (7x3) needles, or longer. The 45k/GA1 type machines use system 214/328 and the 441 clones and Adler 204 and 205 use system 7x3/794.

As JJ mentioned, the stitch length changes when you sew without the feed dog. What many don't expect is that the reverse stitches no longer match the forward stitches, at the old settings of the feet. I find that it is possible to dink with the point in rotation where the needle and inside foot makes contact with the leather, to almost balance out the differences. This is iffy at best, so I usually just watch where the needle is about to hit in reverse and pull down a little on the stitch lever to compensate if too long (reverse is usually longer w/o feeders).

The "patchers" are able to sew into places that no other machine will fit into. They sew in any direction, including up the arm. You can sew patches onto vests, or onto the arms of jackets. You can resew shoes and boots and even sew zippers into pockets with a patcher. As for the 441 machine, all of the dealers on this forum sell very good machines of equal caliber. You will get a good machine and the best after-sale service, at a reasonable price that was unheard of when I started sewing leather.

Back off the pressure spring until the material moves with the needle. Make sure you have just enough pressure to keep the leather from lifting with the needle. Also, use one size smaller thread in the bobbin. If you have 277 on top use 207 in the bobbin. Examine the slot in the throat plate for burrs or sharp edges and Emory them smooth.

Buy the CB4500. Then buy a patcher.

If the needle is hitting to the right of center, something is out of alignment, or you have the wrong "needle system." If the needle bar needle channel was cut for a wider shank needle than you have installed, the point will hit to the right of center. Installing the correct width and length needle will cure that. Assuming you are using the correct needle system, the direction of the cutout above the eye is critically important. Most (but not all) sewing machines must have this scarf cutout facing to the right. You should thread the needle from left to right. The manual should show the correct alignment of the needle.

The only holsters you can sew on a Juki, Consew, Chandler, or Singer walking foot flat bed upholstery grade machine are pancake holsters. You will be limited to a maximum size 207 thread. The large M or DNU/LU bobbin machines can hold enough #207 thread to do plenty of holsters. You machine will be pounding hard with #207 thread, a #24 needle and lots of foot pressure. For leather standard upholstery, use #138 thread, with a #22 or #23 leather point needle. If this is too large, go down to #92 thread, with a #19 or #20 needle.

Where is there anything mentioned about wanting to use it to sew holsters?

These machines are bottom fed, period. If you do anything to the feed dogs you might cause them to gouge the bottom, rather than move it for sewing. Sharp teeth ensure positive feed. These machines are meant for sewing items where the bottom is not normally seen, or which are not markable.

A Consew 206RB(-5), or Juki DNU-1541, or LU-1508 (for heavier materials) are all top of the line upholstery machines. All are able to sew leather, up to a maximum of 3/8 inch, with #138 to #207 thread. They use the commonly available system 135x16 leather point, and 135x17 round point needles. These needles are available in sizes up to a #25. The Consew has a large M style bobbin, while the Jukis have a larger double capacity hook and bobbin.

For those prices you can get a new walking foot machine, not a used one.

The 3650 is not a light weight sewing machine. It is designed for medium-heavy tack work, with heavy thread, which can be bottom fed without concern for the tooth marks.