Uwe

Here's a ruffling foot demo video. Whether this approach will work on your type of leather, I'm not sure. But it's the closest thing I've seen so far. And here's a slightly more elaborate ruffling/pleating contraption made by Kwok Hing: http://www.kwokhing.com/ru/

I knew my ears were ringing for a reason. I posted my wired floor pedal mod/hack in the other, duplicate topic:

Some Efka motors have pedal options for standing workstations. If you don't have a grand or two to spend on a high-end Efka motor, you can buy a cheap three-part servo motor like a Consew CSM1000 for around $125 and hack/make your own wired floor pedal. I once built something like that for a table-top portable setup for a Durkopp Adler 69.

The machine looks a lot like a Durkopp Adler 67 type machine (Pfaff 145 also uses similar throat plates). That foot in the picture looks a lot like a plain top roller foot riding on a normal bottom feed dog. How they get the material to ruffle, I don't really know. You can't really see the material going into the machine in this picture, or whether it really gets ruffled in this step. If the leather is thin enough you can perhaps ruffle it by purposely unbalancing the thread tensions so that the bobbin thread always gets pulled all the way to the top. Then the taught top thread holds the stitch line back while the bottom feed pushes the leather backward, thereby ruffling it. But that concept only works with a single layer and with bottom-only feed, and it may only work in my head, not in real life. But I've seen a similar ruffle effect happening while sewing fabric on a bottom feed machine when my top thread accidentally got caught on something. Your leather ruffling sample looks much too thick for that approach and you're stitching the ruffled top part to a straight bottom layer to lock in the ruffle.

I think that diagram shows the exact same parts, just assembled and separately, from a slightly different angle. 91046 is the complete hook assembly, 91044 is the frame that is part of the 91046 assembly. The page from the 45K68/69/71 parts book shows hook assembly 91774, which consists of individual parts 91772, 91771, 91043, 91795

I had been wondering about the same thing some time ago. I have a dozen or so aftermarket 91774 open frame 45K shuttle hooks. I suppose there's bit of tight spot on the corner of a closed frame hook ( similar to my Adler 205 video.) There's probably a smoother ride for the thread to drag along the smooth edge of a closed frame hook as opposed to bouncing down a few steps on a open frame hook. The closed frame hook likely is more rigid and dimensionally stable, less likely to twist or bend. I'm wondering if open and closed frame versions are interchangeable in Singer 45K models. If anybody recognizes the manufacturer's mark on my aftermarket hooks (looks like an H inside a G) please let me know - I've not been able to find a reference.

Your thread should be somewhat taught after the first thread guide pin (use both holes in the first pin as Bob suggested.) When your thread take-up lever pulls more thread, it should not pull a whole bunch of thread from the spool and make it go slack/loose, thus allowing it to curl up like that. Experiment with wrapping the thread in a spiral fashion (rather than straight up-and-down) through the guide holes to see if it helps. As for teeth mark on the bottom, you're somewhat limited with your options, since your machine is a bottom-only feed machine. If the feed dog had no teeth, it would not be able to move the material reliably, causing uneven stitch length. There are special feed dogs with a sticky rubber coating available for some machines, but I doubt yours is one of them. You can try easing up on the top foot pressure until it is light enough to hopefully lessen the marks from the feed dog, but still strong enough to help feed the material evenly. Other sewing machine designs use needle feed and/or top feed in addition to bottom feed, allowing the machine to move the material reliably with fewer/lighter marks on the leather.

The Pfaff 145 H3 uses 134-35 needles (My Pfaff 545 H4 uses the System 190 needles), according to the Pfaff 145 manual. I bookmarked Constabulary's link to that needle vendor - nice comparison charts for the systems in question! The 135x16 or 135x17 system is only 0.8mm longer in needle's butt-to-eye distance compared to the 134-35 system. That tiny difference might be compensated for via needle bar adjustment without any trouble, as Constabulary suggested.

Hook assemblies for both Pfaff 145 and Pfaff 545 are readily available for around $80 on Ebay. I'm not sure if the 545 hook's bobbin is that much bigger to justify the effort of a retrofit. I took a few basic measurements off the hook from my Pfaff 545. You can compare them to your 145 dimensions and see if it's worth bothering.

Wow, nice work! It's clearly a labor of love and it shows.

The cheap and perfectly functional way to do it is with a little magnetic, battery powered laser guide attachment. I think I got mine at Harbor Freight for less than $15. These are also available on Ebay for $12.50 . I also installed a fixed laser guide with a wired power connection on my Pfaff 335 once (the white LED spot light is from IKEA) . You can do a similar thing on a Cowboy 4500. Available on Ebay for around $15.

I'm under the impression that all Cowboy machines enter the country through Ryan O. Neel of Neel's Saddlery in Ohio (sad looking website but big YouTube presence with Cowboy demos) If a particular dealer doesn't carry a certain Cowboy machine, Ryan should have access to all Cowboy machines and he sells them directly, too. I personally favour the Juki-LS 341 design over the Pfaff 335, mainly because of the vertical axis hook, comparatively huge bobbin, and descending feed dog. That slim 335 arm comes with a few compromises, I think. Each machine design has its own advantages and shortcomings, you just have to decide which ones are important to you.

I got my Consew 104 set up in a test stand and did some stitching earlier today. I made a demo video for somebody who's interested in buying the machine and wanted to see it work. I thought I might share the video here for general entertainment. The machine is quite a different animal from what I've worked on before. I really don't see how a lockstitch machine like a Singer 20U can produce a stitch like that. I also think this Consew 104 would be quite capable of putting embroidery designs like monograms and swirly designs on garment weight leather. I'll try that out on Sunday.

Check out this thread on Singer 29K60 info including threading. Make sure can pull the thread manually and that it's not caught anywhere.

A nice, thorough tutorial on that machine, with threading details and all.

Perhaps something in your tension release mechanism is stuck and keeps the tension discs apart. You should be able to feel a distinct difference in tension when you pull the thread manually and change the tension setting. If the thread tension doesn't change as you dial the tension knob, you have to figure out why.

Post a picture of how you have your machine threaded at the top. Are you sure your thread is even between the tension disks? Sometimes it takes a little effort to snap the thread between the disk, don't just loop it around them.

Are those watch straps machine stitched? Even if you manage to sew parts of the stitch line on a machine, some details will have to be done by hand. Most regular machines will have throat plates and feed dogs much too big for those tiny stitches that close to the edge. You may want to consider using a cylinder arm machine that has optional throat plates designed for "small operation". I think your watch straps qualify for small operation (with surgical precision.) I've not personally used the feet and throat plates shown below, but they seem like reasonable candidates to consider. The came from the Kwok Hing page for Pfaff 335 accessories. The 335 S3 Needle/Throat plate and the 335 S4 feed dog seems about the right size for those tiny stitches on your watch straps, and without leaving too much of a hole in the plate for things to get caught up in. For matching feet, it seems to me the KP335LB could be modified similar to what I did in the video (grind off areas inside dashed boxes) to sew extremely close to the edge and staying clear of the raised part of those straps. Alas, you won't know for sure until you try it out.

I first saw this concept on 441 style presser feet (photo from Toledo Bob's website):

Here's one approach that might work, using a modified outer presser foot and a suitable throat plate:

Technically yes, but it's not easy and involves a couple of other parts, not just the hook.

In defense of Consew servo motors, I recently put together a $110 Consew Premier CSM550 motor with a 50mm pulley and a 3:1 speed reducer to power my Consew 225. Below is a video of this combo sewing 6.2mm (15oz) veg tan leather using size 138 thread and a size 23 needle (I misspoke in the video). To me, this cheapest of servo motors plus a speed reducer (that cost more than the motor) leaves little to be desired in terms of consistent low speed control and punching power. I'd love to see somebody do this with a clutch motor.

I think you mean Cechaflo on Youtube. He's a master of the manual step backwards. It seems he only uses his machine's reverse lever when he doesn't care where the stitches go.

I had a similar problem when I was working on my Juki LU-563 clone. In that particular case the issue was resolved by shifting the timing belt by one notch. It seems your problem is similar, except the Pfaff does not have a timing belt to synchronize upper and lower drive shafts. Perhaps there are marks on the drive gears that need to be aligned. Here's how the machine worked after the timing belt adjustment (and re-timing the hook):

The reverse lever should not be bouncing up and down as you sew. It's often an indication that something involved in the feed mechanism is hitting a limit and something else compensates for it. I'd recommend spending some quality time with the Singer 211G Service Manual and comparing the suggested adjustments to your machine's. Sometimes a less-than-max stitch length is due to the feed dog starting to move backwards before the needle pierces the material (or starts to move forward before the needle exits the material.) Removing the material and turning the machine over by hand will allow you to see what's going on/wrong and make corrections.