Uwe

The folks Leather Machine Co. should be able to tell you if the screw in the handwheel has Loctite or other glue on it. With or without Loctite, make sure you use the largest screw driver you can securely fit into the slot of the screw to get maximum torque without slipping. The concepts of setting the positions for needle positing are not really brand or model specific. There’s no really hard rule and your preference may play a role. Exactly how you set the position depends on the specific position sensor and motor controller you use. On my Juki LS- 341 (which the Cobra Class 26 is a clone of,) I set the needle-down position to be after the hook catches the thread loop and the tip of the hook is at 12 o’clock (a quarter of a hook turn past the needle). In this position the loop is securely caught and the needle is still in the material to pivot the material around when making turns. For needle-up position, you can either set it to when the needle is a top dead center (for maximum foot lift and needle clearance) or when the thread take-up lever is a the very top (knot is pulled tight, good position to remove material, but needle is already on its way down again.) I use the take-up lever at very top position. Whether or not you can set each needle stop position independently depends on the needle positioner hardware and motor controller software. On my needle positioner (which has just one physical sensor) you set one needle position manually via the indicator light for the sensor. The other needle position is offset my 180˚ by default and can be fine-tuned via settings on the controller to advance or retard the second needle position. Some needle positioners have two physical sensors and you set each position by adjusting the position of the sensor discs inside. Please post a link to video you referenced, and then post some photos of your particular setup for the needle positioner installation. I’m not sure how you were able to install the position sensor without removing the center handwheel screw. If the positioner is not securely attached to the hand-wheel and slips, all bets are off. Here’s what the hand wheel of my Juki LS-341 looks like: My installation required the use of the adapter that is held in place by a center screw that replaced the original one in the hand wheel. The green light comers on when the sensor is triggered, for manual adjustment of the first needle position. I rotated the handwheel into the precise position I wanted, then I loosened the sensor collar and rotated it until the light came on, then tightened the collar again.

Here are the Durkopp Adler 268 manuals and leaflets I have in my archive, just to actually attach them to this topic in one place (since search engines are going to be pulling up this topic for Adler 268 manual searches in the future). Durkopp Adler 268 Service Manual: DA-268-Service-Manual.pdf Durkopp Adler 268 Parts List: 268 Parts List.pdf Durkopp Adler 268 Owners Manual: 268_gb.pdf Durkopp Adler 268 Leaflets Part 1:Leaflets_Adler_class_268_part1.pdf Durkopp Adler 268 Leaflets Part 2: Leaflets_Adler_class_268_part2.pdf

Looking at the Adler 768 parts list (durkopp_adler_768.pdf), the part numbers for the feed dogs begin with 0768. This indicates that the feed dogs are a newly designed part for the 768 generation and unlikely to be compatible with earlier models. Parts that are carried over from earlier models will retain the same part number. The parts list has a bunch of parts with numbers that start with 0268, 0367, etc. Those parts are carryover parts and thus interchangeable with earlier model generations indicated by the first four digits of the part number.

It takes only a small piece of metal in the wrong place to lock up a machine. Are you sure you retrieved all the bits of the broken needle from the hook area? Did something else break besides the needle? If the needle breaking incident was hard enough and at high speed, something may have slipped out of position and is now touching something it shouldn’t. You may have to do a careful investigation of all the parts that could slip. I’d recommend disconnecting the motor (remove the belt) until you get the issue resolved and the machine to turn over smoothly by hand.

The Adler 268 Brochures/leaflets (Leaflets_Adler_class_268_part1.pdf and Leaflets_Adler_class_268_part2.pdf ) should help you narrow down the possibilities. I would guess it’s an Adler 268-262, or something close to it. It’s hard to tell if it has or had a thread cutter, without seeing more detailed pics. I’d say you can rule out most of the subclasses that have letters in them. It looks like you already found some of the other manuals. Here’s the page at Durkopp Adler that shows what they have available for download in their archives. I had to switch the toggle button from “Exlusive Archive” to “All Data” to see vintage 268 documentation. https://www.duerkopp-adler.com/service/documents-download-center/catalogs-and-brochures/ I’m not sure you absolutely must know the precise subclass. Many of the basic adjustments for hook timing etc. will be very similar among the basic subclasses. Post some more pictures when you get a chance (rear, underside, close-up of needle area, hook covers open, etc.)

Please post some pictures of the whole machine (Front& back) and a close-up of the actual feet you have. It’s very likely you have the standard gauge with Singer style feet. In that case you may simply have the screw inserted from the wrong side. The forked presser bar is threaded only on one side. You need to insert the screw from the non-threaded side in order to squeeze the forks together and hold the foot very tightly. If the screw is inserted from the threaded side, it will screw in just fine, but it will not squeeze the forks together and thus not hold the foot tight - the foot will just dangle loosely from the screw no matter how much you tighten it. And that adjustment wheel on top should indeed change the walking height of the feet. Look at the original Juki LU-1508NH manuals for general instructions … BUT that walking height adjustment wheel was actually not on the original LU-1508NH machines, so you won’t find it in that manual linked above. That adjustment wheel is a feature of a slightly different model. Clone manufacture often mix and match features from closely related OEM variations. Juki may have a dozen variations on the basic LU-1508, but the clone manufacturer makes just one model and puts all the useful features from the variations into that one model. I’d also say don’t worry too much about the “true” NH or not thing, although chances are good it actually has NH specs. If the machine sews nicely with the needle system that’s installed, just use that and enjoy it. If you run out of other useful things to do, you can investigate and verify precise specs, or maybe change needle systems. But don’t let it interfere with enjoying your absolute steal of a machine.

Depending on your expertise in electronics and programming, you can also build your own motor and controller that does exactly what you want. I did that once using a stepper motor and Arduino controller, just as a demo project for a thumb controller retrofit. The stepper motor I had on hand for testing was not suitable for actual sewing, it was super noisy. Here’s the demo video I made of that experiment. Aside from the thumb controller, you can also see the super slow ramp-up speed I got with the foot pedal. Using a modern servo motor like the Clearpath line made by Teknic you could build a usable system that truly ramps up as slowly as you want with no jump from zero to some minimum starting speed. Cost would be around $700-$900 for the parts, I imagine.

EFKA is one of the high-end motor and controller options for sewing machines, for a price (roughly $1,500+ range for motor+controller+control panel). These are designed for industrial production applications and are not targeted at the home/hobby market. The spec sheet for DC1550/DA321 combo states a minimum starting speed of 70rpm. I have a feeling this is the state of the art in motor controls. For speeds slower than 70rpm, you have the option of using an electronic thumb controller, that you can twirl as slowly as you want with your thumb.

Just trying to embed the video in the post … https://www.youtube.com/watch?v=4Uc7uEdmcK4 Hmmm, not sure why I can’t do this right now.

I made a short demo video showing the 100rpm startup speed on my Adler 30-1 and Juki LS-341 using the 1500 watt servo motors I source on Alibaba.com. They cost around $150 each shipped to the US (minimum order quantity is 4). I’m not trying to sell these motors, just giving a demo of the motor that works for my needs. https://youtu.be/4Uc7uEdmcK4

Maybe I’m missing something, but why are motor mounting options a secret to be discussed in private?

The short answers is NO, none of the brushless sewing machine servo motors you can buy today can do 1rpm, which is what you’re implying by starting from 0rpm. 1rpm means you’ll wait a minute for the motor to make a full rotation, three minutes or so for the machine to make a stitch. Not really practical. The spec on most servo motors should really read: 0rpm, then 300rpm-2000rpm. There is generally nothing between 0rpm and 300rpm. Most servo motors I have worked with have a starting speed of 300rpm, some can start at 200rpm, very few can start at 100RPM (including the 1,500 Watt motors I’ve been buying.) None of the motors I’ve seen can start slower than 100rpm. With a small pulley, that 100rpm starting speed translates to a stitch every two seconds or so on the big 441 style machines. That’s all I want, personally. The minimum starting speed is kind of a design feature inherent in servo motors, and the controllers that drive them. While it’s technically possible to make a servo motor start veeeery slowly (or one tiny step at a time), the sewing machine motors on the market here in the US are not designed that way.

Great manual find @kgg ! A new needle may be all that’s need to fix the problem. The snag you hit may be an actual snag or a deformed needle tip. “If in doubt, change the needle” is generally good advice for sewing problems. P.S.: For those unfamiliar with the layout of Juki Engineering manuals, they’re intended to be read in side-by-side page mode to see two pages next to each other, like in an open binder or printed booklet. The standard adjustment info will be on the left, the how-to-adjust info on the right. That way the corresponding information lines up horizontally from left to right, especially if there are multiple adjustment topics on the same page. Depending on your PDF reader, that’s either easy or nearly impossible to do. Example:

I think it’s a bargain. A well-made copy of the Dürkopp Adler 204-370. Very good design and one of the best heavy duty flatbed stitchers you can find.

This hooks and awls business would surely benefit from a proper naming convention, like needle system numbering. I’ve never worked with a Champion stitcher, so know little about them, sorry!

I have a bunch of Champion awls, but no hooks. Send me a PM if you’re interested in the whole lot ($100, 30ish packs of 12 awls ea.) Not interested in selling individual awls or packets, sorry!

That’s a copy of a Seiko CW-8B (Consew 227 in the USA) Here’s the manual: Seiko CW, LCW, NCW Operator’s Guide.pdf

I have a feeling the design of that class of machines may not be capable of doing what you want, namely to perfectly match forward and reverse across the full range of all stitch lengths. You can fairly easily perfectly match forward and reverse for a particular stitch length using the various limiting devices. The design of that feed mechanism in those machines is about a century old and they didn’t invent reverse until a few decades later. I’m guessing it was not a priority for the target customer, i.e. factories where the operators were generally not allowed to change settings. If anything, the design focus was on preventing the operator from making changes, while allowing the resident mechanic to easily dial in one perfect, matching stitch length for a specific operation. If an operation required a different stitch length, they would set up a separate machine just for that. The hobby/craft user who frequently needs to change stitch length was not a major factor in the design of the machines. Modern designs are a different story. They often have fundamentally different feed mechanisms, many of which do allow to match forward/reverse through the entire range of stitch lengths, or easily switch between two stitch lengths via a simple switch. If you look at anything in the current production lineup for upholstery class machines from Pfaff/Adler/Juki etc., they will very likely be able to do what you desire. A vintage Juki LU-562 is very cheap in comparison to the new designs, but it does have some limitations. See if you can live with the limitation, and if not, start saving up for a modern machine..

Your best bet might be asking the folks at Global (https://globalsew.com). They’re based in the Netherlands. Global’s Model descriptions indicate that only the LP9971 R-LH has reverse. LP 9971 – Single needle postbed machine with top driven roller, wheel and needle feed with standard hook. LP 9971 C – Same as LP 9971, but with Chinese hook. LP 9971 R-LH – Same as LP 9971, but with manual back tack and large hook. LP 9974 – Double needle postbed machine with wheel feed and top driven roller presser ( no needle feed) and equipped with standard hooks. Standard needle gauge 2,4 mm. LP 9974 C – Same as LP 9974, but with Chinese hook. Their manual for the 9971 machines shows an old Singer 111W style feed motion eccentric. I doubt that you can upgrade this to add reverse. https://globalsew.com/wp-content/uploads/2017/03/LP-9971-TD-Manual.pdf

With an “8B” in the name, chances are good it’s a clone of a Seiko STW-8B, sold in the USA as the Consew 226r, and cloned many times over. https://issuu.com/davidmannock/docs/seiko_stw-8b_226r_owners

As for hand knobs I really like the one I used to replace the missing one on my Adler 30. It works great, looks kinda pretty and was easy to adapt for my installation. I got mine on Amazon for $15 (https://www.amazon.com/gp/product/B07P6ZRVY2)

In my book the proper way to solve this issue would be installing a servo motor with needle position sensor. You may never have to touch the hand wheel again. Aside from that option, the hand wheel on this DA 669 is designed a little different than standard balance wheels on many vintage machine. The hand wheel is separate from the pulley and it’s just a piece of plastic that’s attached to the pulley via the three screws you see. You can probably make your own, larger version with simple tools like a reciprocating saw and a hand drill. Or ask a friend who has wood lathe skills or a 3D printer, or something along those lines. A plain round piece of wood with a hole in the middle and three mounting holes would probably work just fine. Use longer screws to attach it if need be.

Yes, that’s a suitable motor, I think. You’ll have lots of flexibility mounting the speed input, motor, and control box wherever you need them to be. You don’t need to use the mounting brackets that come with the kit. You can create custom mounting solutions like I did in my setup shown in the pictures I posted earlier. Your table is not designed to accept the standard 3-hole mounts, so you’ll have to get creative. These motors, controller, and speed input also lend themselves to simple clamping installation, for testing or permanent use.

Great, she’s a beauty! The decals are gorgeous and in great shape. You might be able to mount/clamp a servo motor under the top surface at the rear to drive the big, currently unused pulley. That would act as a HUGE speed reducer (perhaps too big to use with a position sensor) Disconnecting the linkage between the pedal and the big wheel would allow you to connect the existing pedal to the speed input. You’d loose the ability to pedal-drive the machine, but the front hand wheel is a great option for slow manual stitching.

This feels more like a smart phone support forum at times. A simple “Samsung photo resize” search reveals these instructions: https://www.samsung.com/sg/support/mobile-devices/how-to-resize-photos-in-the-gallery-app-on-your-galaxy-phone/