Vinculus

I thought I'd give everyone an update on how all of this went: Giving up on getting a custom 40 mm. pulley made, since I was quoted €150 for it, I went another route. I ordered a 40 mm. 15 mm. straight bore pulley from College Sewing, thinking I could simply make a shim to make the fit around the motor shaft acceptable. Turns out the bore portion of the pulleys sold by CS are about twice as wide as the stock JK-510A motor pulley. This meant the motor pulley shaft was not long enough for the new pulley to fit. Solution: I took a hacksaw to the protruding end of the new 40 mm. pulley and simply sawed it off, leaving it narrow enough for the motor shaft to reach all the way through the pulley bore. I made sure to file it all level afterwards where the hacksaw left unevenness, so the pulley would not spin off-center because of surfaces not being flush with each other. Then a new problem arose. I couldn't simply attach the narrowed down 40 mm. pulley to the shaft because 1) it has a 15 mm. bore as opposed to the 13 mm. motor shaft, and as such it would only tighten all the way down to the motor body and simply get stuck flush with the motor casing; unable to rotate. Luckily, it appears the motor shaft has been turned down to 13 mm. from 15 mm., so there is a small portion of the shaft closest to the motor that still has a diameter of 15 mm. From here the solution was simple: I took a DIN125 round washer (14 mm. inner diameter) and slid it onto the motor shaft, so that it rested upon the 15 mm. innermost portion of the shaft, leaving the necessary space between the pulley and motor case for everything to spin freely. All that was left after this was making a beer can shim to get the 13 mm. motor shaft to accommodate to the 15 mm. pulley bore. The machine now sews at a very manageable slow speed and I am very happy with the final outcome of this project. In conclusion, however: I would not recommend getting a Jack JK-510 servo motor if you want slow speeds without an external speed reducer. Replacing the original pulley requires far more work than it should. Typically it would be a 10 minute job. In this case it took hours and a lot of improvisation for a result that is still not optimal; but rather works okay.

Haha, I was wondering where I would get the alu to make the shim. That's brilliant.

Yeah, but I didn't end up buying the motor in the first post. Instead I got a Jack JK-513A from College Sewing. Turns out it has a non-standard bore, as seen in the attached picture. I will probably try dikman's suggestion and buy a 15mm bore pulley and wrapping some sheet aluminium around the motor shaft; at least before investing in a custom made pulley.

Oh well, custom made it is, then. It'll work itself out eventually I guess.

Could you give me a link to where I can get a 12 or 14 mm. bore pulley?

Well, it wasn't easy, but I got the stock pulley off. It does indeed appear to be some kind of non-standard size and configuration. The shaft is 13 mm, bummer. What is really weird is how the key for the pulley bore is a separate piece of metal that was just jammed in there. I was under the assumption it would be part of the actual shaft. Is this normal? See attached pictures. Looks like I'll have to get a custom pulley made. Sucks!

College Sewing told me the same, and even added that the stock pulley is "fixed". This is obviously not true, since it's fastened with a regular nut and washer. Anyway, after searching this forum, I found that the Jack motors have a 13 mm. straight bore shaft. This is some kind of stupid non-standard size, so it looks like I'll have to have 40 mm. pulley custom made. I am wondering, however, if a 15 mm. straight bore could work. The pulley has a notch and the shaft should have the key for this notch, so it's not like a 15 mm. bore pulley will spin around freely. What do you guys think? The pulley might rotate 2 mm. off-center, but otherwise it should work, no? I'll probably have a 40 mm. pulley custom made anyway. At 200 rpm, which is the crawling speed of the motor, it's still too fast for the delicate and non-linear work shoes require. Should probably think about building a speed reducer as well.

Thought I'd give you guys an update on this. I received my Jack JK-513A servo motor from College Sewing today and installed it - and everything works, so thanks for all the help! It still sews a little fast at the lowest speed setting, so I will be getting a 40 mm. pulley for the motor. Probably won't bother with a speed reducer since it seems like a lot of work that I don't know how to do. Do any of you know what kind of bore the JK-513A pulley uses? I don't feel like removing the original one just to find out and put it all back together again

Thanks Tom! I switched to a lighter thread (Serafil 40/tex 70) and actually had to decrease the top thread tension by a lot, but it seems to be making nice stitches now. I also found it helped to hold on to the ends of both of the top and bobbin thread when starting a seam. Otherwise the threads would get "sucked" under the feed dogs and birds nest galore. Guess it's just a learning process.

Alright, so I picked up the machine yesterday. The stitch length lock lever is there, so it was probably just missing at the time the picture was taken, but the seller has installed a new one. As a side-note, it's a model 68-2. Since it doesn't have any motor at the moment, I've only been able to test the machine by rotating the handwheel manually. It sews nicely on the piece of folded chrome tanned leather that came with the machine. When I tried doing a few stitches on a piece of 6 oz. veg tan leather, however, it made a mess on the underside of the material and didn't properly tighten the bobbin thread. It was all just a cluster of thread and the bobbin thread laid in the middle of it. The top thread also got stuck where the bobbin thread comes up at the end of my row of stitches. I did a few rows of stitching, but they all ended up the same. When I put the chrome tanned piece back and did a few stitches on that, it worked fine again. This is probably just a simple tension issue, but where might the adjustment need to be made? Gotta say it's pretty confusing to be using an industrial sewing machine for the first time. Lots of growing pains!

Weird, the listing for the machine says it doesn't use air. Anyways, I ordered the JK511/513 motor for the machine and will pick up the machine itself on Thursday. Hopefully everything works out. Really, really looking forward to closing uppers with a roller foot machine.

Thanks again. What would I do without you guys...

I guess it's possible that it's broken, but picture googling other Adler 68s, it looks like some models just have a round knurled thumb nut and others have a lever knob. This one has the same configuration as the one that is soon to be mine, for instance. Also, it's impossible to find a manual for this machine that isn't only in German. Hope it's pretty self-explanatory, being a very bare-bones machine.

Phew, good to know. I'm actually very surprised that these motors are so affordable. When you think of the cost of industrial sewing machines in general, affordable is usually not a key word. Just hoping that the machine doesn't have a lot of parts near the end of their lifespan. Adler parts are definitely not affordable! The seller runs a shop dealing used shoemaking machines, so at least I know it's been serviced.

Also, how difficult is it assembling one of these new motors to an old stand? While I can be crafty, I would much prefer a simple job.

Thanks! I hadn't even thought of buying "local" since that's usually a lot more expensive, but those prices are good! Looks like I'll be getting the machine, as the seller would like to trade my Singer 29K72 for the Adler 68 with me paying €100 in-between. Original list price was 500, so I feel like that's a decent deal.

So I have the opportunity to buy this Adler 68 here in Finland, but it comes with the original clutch motor. That's no good for me really, since I make shoes and need the control and low speeds of a servo motor. The seller will knock off $100 of the listed price if I take the machine with no motor at all, so that I can buy my own servo motor for it. Post bed machines are rarer than hen's teeth here unfortunately, and I sorely need one to replace my Singer 29K72. Missed out on a Pfaff 471 with a servo motor already, the only one of its sort being sold here in like a year... Now, I'm on a very tight budged here, being a poor student. I've found some seemingly affordable brushless servo motors on eBay, like this TS550. I have absolutely no experience with industrial sewing machines, so my question to you more knowledgeable people is as follows: will this motor work? Will it even fit? Are these things "universal", so to speak? The only thing I know that I need is that the motor must be compatible with 220-240 voltage and be single phased. Alternatively, could I install a "suicide knob" to the sewing machine's wheel and hand crank it? I've become so accustomed to hand cranking machines throughout the years that I would almost prefer this. But the Adler 68's hand wheel looks mighty tiny and I wonder if it would even work. Sorry for all the stupid questions, I'm obviously new at this.

Hmm, might try the brake fluid. Anything to avoid mechanically removing the screw really. After making some more adjustments to the eccentric stud and needle clamp, I got the machine sewing relatively well. Here is a shoe I did yesterday. It's not perfect, but slowly getting there.

Alright, good to know - thanks! I think I'll try and minimize the slack anyway since it can't hurt, so I ordered basically all the rack box parts to rebuild it. Just gotta build up the courage to drill out that old set screw first. Will keep everyone updated once the rest of the parts arrive!

Is this amount of slack too much, or is it within acceptable amounts? Video here: http://gfycat.com/PointedSpryBoar I've never handled one of these before, so I have no idea how much is too much.

Blergh, I wish it would be possible to have the machine serviced easily here in Finland. I stopped by the only sewing machine shop in the city the other day, and the moment I mentioned "shoe patcher" they just went NOPE and wouldn't even talk to me.

Is there anything more to timing the hook and needle than to adjust the eccentric stud so that the hook reaches its correct leading position when the needle comes to a slight stop in its lowest position? Dang, that was a long sentence with no stops. I've followed the guidelines in the manual to make that adjustment, which seems to be holding.

I have already purchased the necessary parts from College Sewing, but thanks The problem is getting the old ones loose so I can replace them, haha.

Yeah, I knew that - I guess the previous owner did not. The needles that came with the machine were Groz-Beckert UY-113 GS. Those are a full 4 mm. shorter than 29X4/332L needles, so I'm amazed the machine would stitch with them at all. The machine still skips stitches here and there when sewing more than 3,5 mm thick veg tan, but I suppose that is around its limit anyway. Now if only I could get that pesky shuttle carrier set screw out and replace the part...

Well, the problem solved itself. I got new needles today, Schmetz 332LL. Turns out those are significantly longer than the hundreds of needles that came with the machine. No skipped stitches anymore! Guess the original owner used the wrong needles that sort of worked because it's impossible to get the right ones domestically.