Uwe

Start cheap and learn until you know what you're doing and really need/want. If the Juki makes a nice stitch on what you want to sew, go for it - buy a nice servo motor with the money you save. Later, if you decide you need a walking foot after all, just buy a head. You already have a nice table and servo motor. The Juki head by itself is worth perhaps $100-$200. You can swap heads in and out of a suitable industry standard table in just a few minutes. I bought a Sunstar machine similar to your Juki just for the table, actually. That nice table now holds my Chandler/Adler 67. I put the Sunstar head in the crappy table with clutch motor the Adler originally came in and sold it cheap. I now have a nice table/motor/adler setup.

Some leather types are tanned to hold impressions and wet-molded shapes for making relief designs using stamps etc. (veg tan leather is usually in this category.) Other leather types are tanned more spongy/springy to resist impressions and bounce right back to the original surface shape (e.g. for sofas and car interiors). Some leathers fall between these extremes. The problem arises when folks use leather designed to hold impressions with machines that make unwanted impressions. Likewise, trying to make a relief design on a leather that doesn't hold an impression is a futile effort.

You can also watch my timing video for the Adler 67 to get a rough idea of what's involved. Despite the 67 being a flatbed machine with a small bobbin, you'll recognize many details on your Adler 169. The hook design (and timing adjustment) is nearly identical to your Adler 169. Your hook timing spec calls for a needle rise of 2mm (instead of the 1.75mm in the video). Between the video and manual, you should get there most of the way.

The Adler 169 Service manual would be a good starting point. I'd compare the machine to the target settings to see which ones are off the mark and need adjustment. Then you follow the manual to make those adjustments.

I made this little platform to allow using the Durkopp Adler 205-370 in Needle+Upper feed mode rather than compound feed. Turning off (removing) the bottom feed dog can help minimize marks on the bottom of the workpiece for certain sewing operations. The idea popped into my head while contemplating a topic in another thread about working with veg tan and prefinished leather. Here are some pictures of the platform:

Nice machine! If I were you, I'd explore the magnetic guide and edge guide feet option first. That nice flat bed really lends itself to a magnetic guide solution. A swing-down guide would be a minor pain to install.

If you click on the little link thingy it'll take you right there.

I hesitate a little to post this rare earth magnet option, since these magnets are so freaking strong (65 lbs of pull force) they'll probably turn off a pacemaker and can be dangerous with kids around. But they certainly won't move once they've latched onto your sewing machine. $3.72 plus shipping. These have mounting holes to attach a little knob to grab and move the thing:

Can you post a close-up picture of your machine bed near the needle are and one of the back of the arm near the foot lift lever? It'll help a great deal trying to figure out what options might work for you. Without pictures, we're all just guessing as to what you might have. You can either have a bed-mounted guide, or a swing-down guide that mount to the back of the arm. Deciding which is the better option (if at all) really depends on whether you have threaded mounting holes in a suitable place, either on the bed or on the back of the arm. There are some magnetic guides around too that don't require any mounting holes, just a good magnetic flat surface near the needle.

I'm experimenting with throat plates and video setups for my Durkopp Adler 205-370. I decided to make a transparent throat plate from a piece of plexiglas so I can film what's going on underneath. I removed some non-essential bits and pieces from the hook area, too. You don't want to actually sew with this setup, but it's great for documentary purposes:

Most of these industrial sewing machine have some kind of thumb screw at the top that allows you to adjust how hard the presser feet push down. Many people never adjust that foot pressure because it works fine as it is for most tasks and some don't l know they even can adjust the foot pressure. The owner's manual for your machine probably talks about it. On the Adler 205, it's the screw that I'm removing at the beginning and then tighten again at the end of this video:

So within days of deciding that I really should sell my flatbed machines (since I own two amazing cylinder arm machines with beautiful flatbed table attachments), I did what any self-respecting leather worker would do - I bought ANOTHER flatbed sewing machine! This new-to-me Tacsew T1563 was a curb rescue of sorts by way of Craigslist. The Tacsew T1563 appears to be a near perfect clone of a Juki 563 down to little details like oil drip guards, etc. I really like the large bobbin and reverse lever mechanism. It's actually in better shape (after a little cleaning & TLC) than my Consew 225 was when I got it. The mechanics are otherwise very similar to my Consew 225. So now I'm looking for a Juki 563 manual just to have proper documentation, but the ones I've found online are either just okay or really bad quality, especially the pictures. If anybody knows of the whereabouts of good, clean Juki 563 manual in PDF or printed form (buy or borrow), I'd love to hear about it. I'm also striking out finding much (any, really) information on Tacsew itself. Is this a rebadge outfit like Chandler or a standalone clone manufacturer/distributor? Where are/were they made? Any industry insider info would be appreciated.

According to the parts diagram it's the "thread releasing finger". It pulls back the bobbin case a little to let the thread slip through. Leif labs talks about this part in his blog

The only thing that makes sense based on those pictures is that the whole system uses single phase 220V. They just used a different plug to match whatever they had in the wall at the factory. Green is (should) always be Ground and there needs to be 220V between the blue and brown wires. There is no neutral wire (normally white). That's really all there is to it. So one of those transformers should work fine I think. Just change the plug from the four-pronged one to a three pronged one to fit the transformer outlet. A plug like this would be the right one, it's designed for 220V and 15A. The official name is NEMA 6-15P:

In general, to minimize marks on your leather, you want the surfaces touching the leather be as smooth as possible with no sharp edges, have the surfaces be as big as possible to distribute the pressure over a larger area, and have the pressing force be as low as possible while still holding on to the leather and letting the machine make good stitches. No matter what kind of sewing machine you have, it'll take some experimenting with various feet, needle/throat plates and pressure settings. Report back if you find a combination that works well!

I don't want to make your decision any harder, but your issue prompted me to make yet another alternative, a needle feed throat plate. Sometimes the bottom feed dog mechanism is causing more trouble than helping. Some folks use the 205 as a needle feed machine for certain tasks by "turning off" (i.e. removing) the feed dog. This throat plate enables needle feed mode and provides a small flat work surface which is handy for belts, wallets, and other flat work pieces. You remove the feed dog entirely and the material is moved only by the needle and inner presser foot by dragging it across the very smooth surface. It doesn't entirely eliminate marks, but it's a big improvement for certain tasks on my machine. If you need to get hat SUV up the mountain without leaving ANY tire tracks, you need to hire fifty barefoot sherpas to carry it up there. This may be a good option if you have just one or two layers to deal with. Here are two screenshots from my CAD program and a quick snapshot of my prototype:

So when people say "soak it in kerosene" they mean "spray this kind of stuff all over it", and not "fill a big vat/tub with kerosene and submerge your sewing machine in it"? Maybe my imagination just got a little carried away.

You should seriously consider using it as an unrestored historic decorative piece. It would look great as it is in the right setting and your friend would admire your sense of decorating. The problem with gifts often is that the people giving them expect to then see them when they come visit. I personally would not soak it in kerosene (sounds like a very smelly fire hazard,) I'd leave it outside all winter and spray salt water on it occasionally to really get some patina going. Turning it into a shiny AND functional machine may neither be feasible nor in it's best interest.

I often visit Miami Sewing for a nice alphabetized sampling of upholstery/leather machines with a brief description and a ballpark figure to go with it. At least you can tell if something is in the hundreds or thousands value wise.That big white one stands out to me but I'm not sure how practical these monsters really are for our kind of leather work. For leather work, a proper walking foot and cylinder arm is desirable, a chain stitch machine not so much (unless it's a precious Puritan, haha!). At theses kind of auctions, it may be good to get three identical machines and then frankenstein one good one. The other two you can put on Craigslist and say "Sews Everything!" and "Works!", just like all the others do.

The pictures from inside the switch box want to tell the story about incoming power, except I can't quite make out the incoming wires. It's definitely expecting single phase 220V incoming power - that little transformer diagram seems to want ONE power line that carries 220V against a neutral white. What I can't tell is if the incoming 220V is ONE power wire against a neutral white, or between TWO power wires. This is important. A voltage transformer like the one mentioned earlier may actually provide exactly what the machine is expecting, one power line carrying 220V against a neutral white. A few more pictures would help: show more details of the incoming wires inside the box (is the green/blue/brown the incoming one and are there really only three incoming wires?), open the plug at the end of the power wire and show us which wire is connected to which pole inside that plug.

There's a separate adjustment for the manual lifting lever - it's supposed to have just a tiny bit of play when not engaged. The clamping block just above the one I loosened in the video adjusts the manual lift lever. The manual lift lever should be able to rotate to the 11 o'clock position to hold the foot in the lifted position and release the upper thread tensioner. If you can't rotate the manual lift lever easily past the 12 o'clock position it's binding - don't force it! You're supposed to be able to engage manual foot lift lever and then release it again by pressing the foot operated lift above the manual lifting position. If you loosen both clamps at the same time and remove the presser foot, you can pull out the presser bar/shaft/rod out the top (watch out for the little spring between the two clamping blocks.) I did just that last week when I replaced the lifting bracket/strip/blade that hooks between the two clamping blocks - it was broken on my machine. I'm guessing the previous owner forced the manual lift when it wasn't properly adjusted. My spring is 120mm (4-3/4") long. It just peeks out the top a few millimeters (tension screw removed) when I have the manual lift lever engaged. If your total spring length is longer, leave the extra piece out. The presser foot is supposed to push down on the material with just enough force to keep it from moving while the needle is above, not clamp down with a ton of force. Excessive force just makes everything work much harder, and leaves marks on your leather. Fabric generally doesn't care how hard you clamp it down, but leather does care. It also matters how thick the material is, but the proportional increase in pressure for thicker material is usually just right. Take the needle out and lower the presser foot on your finger. If it hurts, it's too much force. If you feel it holds your finger in place without hurting, I'd say you're good for a starting point. Adjust as needed.

Technical documentation that originated in english isn't a whole lot better at times. Good technical writing is a lost art. The exact same thing (a cylindrical piece of metal) may be called a rod, bar, or shaft, depending on who's looking at it and where it is. I've translated automotive technical manuals in the 90's and it's hard work. You really need to be an engineer in addition to knowing both languages to do it even remotely justice. If you just look up words in a technical dictionary, you end up with documents that read like the translated sewing machine manuals.

Not sure what you mean by upper foot. The inner feeding foot and outer presser foot perform the same lift relative to each other due to the design of the linking arm. By adjusting lift for one as in the video, you automatically adjust the other. They should always be lifting equal height.

I made a little video about my interpretation of that section in the service manual. It's not a literal interpretation and I took some liberties involving a stack of quarters instead of a proper gauge. The German version of the service manual is a little opaque even to native Germans, haha. It sounds like your clamp that ties the articulating arm to the presser foot shaft might be loose. In any case, here's the video - I hope it helps:

Yup, my magnetized magnets work way better than the ones that are not magnetized, haha. I agree with you. I updated my youtube videos by adding a note about the hook removal not being necessary. I just wish I'd known six months ago. On the plus side, removing the hook no longer scares me.