Uwe

Good tip, DC! I actually have a Mitsubishi CU-865 project machine, but the hook cover is missing (as it turns out all three of my small cylinder arm project machines are missing the hook cover - argh!) CU-865 parts appear to be totally unavailable these days - my supplier just shows *NLA* for the last few CU-865 parts I tried to order. But at least I can use it to take some measurements to make my own hook covers.

The question is, can you put a closed Adler 69 cap on a Pfaff 335 to avoid things getting tangled up in the open hook area? I'm hoping somebody has both machines sitting next to each other for a quick trial. The Pfaff 335 uses open caps: and The Adler 69 uses closed caps:

Tennessee Attachment Co. sells all manner of binding related things. The website hasn't quite made it into the current century, but they do have a Flyer for Binder Setups that includes the kit shown below :

I have a like-new TechSew 2900 patcher that I got along with a few other machines from Recaro, the child safety seat people. I don't think they used it much, if at all. It was sitting shrink wrapped on a palette with a big "Storage" sign on it. The head is $1,150, on a table with servo motor it's $1,350. It's a very nice machine, still available new from TechSew for $1,895. I can ship the head within the U.S. for around $100-$130. If you want/need the table and servo motor you'll have to pick it up in the Detroit area. Here's a video that hopefully shows the condition and functionality of the machine well enough:

Establishing sewing machine lineage and pedigree is a messy affair. The Juki DNU-241 started life as a Yakumo 280L manufactured by Nakajima and later also sold as a Nakajima 280L. Juki eventually bought Nakajima and incorporated some of the Nakajima machines into the Juki lineup under new names. An adopted original, if you will. Consew 206RB1/2/3/4/5 machines were manufactured by Seiko until a few years ago. Consew was a brand/entity created by Seiko to sell their machines in the U.S. back when "made in Japan" evoked the same emotions that "made in China" does now. Consew and Seiko separated/divorced at some point and Consew changed sourcing of 206RB5 from the re-badged Seiko originals to a Chinese clone manufacturer somewhere in the middle of the 206RB5 model run.

The motor part of the modular Efka Variostop system would be fine with a VFD or a Static phase converter, but the electronics inside controller box would likely not be happy. On my modular Efka Variostop system here in the U.S., the main power connection box has four wire connectors, one for each of the three power wires, plus ground. All three power wires continue on to drive the 3-phase motor. Only two power wires continue on to the control box to supply single phase power. The motor itself does not care how "clean" the incoming power is (perfect sine wave, choppy steps, or wobbly waves). The controller box DOES care and needs the clean, perfect sine wave power for its electronics. With a static phase converter only one of the three phases is truly "clean" (the other two phases are wobbly weaklings mainly there to help start a motor from a standstill). You'd have to make sure that the two wires carrying the original, single phase, perfect sine wave carry on to the controller box. Many VFD units output stair-stepping sine wave approximations on all three phases which are not suitable for powering electronics. Rotary phase converters do output perfectly synchronized pure sine waves on all three phases, which is why they are used on systems that integrate both motors and electronics ( e.g. CNC mills) You could, theoretically, power the two modular parts of the Efka Variostop system with separate power supply lines, which is what DC was suggesting above, I think. You could power just the motor with whatever phase converter you like. Then wire up the controller box separately, with a clean single phase power supply line. Some of the statements above vary depending on which country you live in and what type of power supply you have coming out of the wall. Personally, just writing this up gives me a headache and "don't bother" vibes. A nice new servo motor sounds like a GREAT option to me right now.

I'm curious if the manual states that or if a sales person made that claim. Very few machines in that size and weight class handle 207 thread well, if at all, or for a long time. A lot of things have to come together to operate machines at or beyond their design limits. I once got a Consew 225 to sew 207 thread ( https://youtu.be/zwVGkT0e5BU ) , but who knows if it would do it for long. Is your machine a plain DNU-241 or a DNU-241H? That little extra "H" sticker may be prone to falling off I suppose. I've not been able to find any info or specs on a non-"H" DNU-241 machine. If you're going to switch machines, I'd make the seller demo that it handles 207 thread on YOUR materials. Otherwise you're just swapping machines and inherit a different set of potential problems. The RB4 and RB5 machines are very nice, but really more of the same just like your Juki, with subtle differences at best. SInce you're making bags and other non-flat pieces, you should really consider getting (or adding) a cylinder arm machine with a barrel shuttle. Those hook designs are a totally different animal and handle thick thread MUCH better. The usual suspects include 441 class machines (e.g. original Juki TSC-441, copies like Cowboy 3200, 4500) or an Adler 205 class machine. Those will definitely sew 207 thread (up to 415) all day long with grace and without complaining.

Page 6 of the Efka Variostop base manual (EN_BA_FKV_5(5)_090595.pdf) does talk about using single-phase and three-phase motors with the Variostop systems, so it is technically possible. Whether you'll be able to find a suitable single-phase motor is another questions.

I have a strong feeling (but no proof as of yet) that the Efka Variostop systems can operate with both 3-Phase and single-phase motors. The controller box itself actually runs on normal single phase power and it only controls the clutch/brake mounted on the motor, not the motor itself. The motor simply runs at full speed all the time. A call to Efka in Germany may a really good option before you start to dismantle things. They will be able to tell you which, if any, single phase electric motors are available for the Variostop systems.

As for running 3-phase equipment on single phase power, you really need a rotary phase converter that look something like this: Those rotary phase converter are big and heavy - it's essentially yet another 3-phase electric motor that's even bigger than the one you're actually trying to run. That 3-phase motor is tricked into running on single phase power and then acts like a 3-phase generator. The rotary phase converters cost considerably more than a nice, modern servo motor that does not require 3-phase power. You can build your own rotary 3-phase converter, but that's not everybody's cup of tea. There are all-digital state-of-the-art phase converters, but they cost even more. To me it does not sound like it's a viable or even desirable option to make your current Efka Variostop setup work in your home setting. You may indeed be better off removing all the automation bits and air cylinders and convert the machine back to a simple manual setup, with a nice servo motor. Those Efka Variostop setups are actually awesome when used in the right setting. I just got done refurbishing a full-function Adler 467 that also has a 3-Phase Efka Variostop motor and controller. It's rather amazing to observe the choreographed dance of air cylinders and electric solenoids during the automated functions. While intimidating at first, it was also a little addictive to use while testing it. Alas I have no use for it in my home setting either. I hope to sell it to somebody in an industrial setting to do real production work.

I've never even heard of this machine until just now, but it looks like a very nice - and very complex - machine. You'll need to spend some quality time with the service manual for Durkopp Adler 8967 (8967_instructions_for_service.pdf) I'm not an expert on thread cutting mechanisms, but I was just working on the thread cutting mechanism on my Adler 467 yesterday. It also did not want to cut the thread reliably - I had to advance the hand wheel a quarter turn to complete the cut. On my machine the fix ended up being an adjustment inside the needle position sensor. My NP sensor has one disc that is used for positioning during thread cutting operation. I had to rotate this disc a little to change how far the knife moves during the cutting cycle.

The Cowboy CB227R seems like a fine machine and would probably do most of what you want to. I think you should also pay a visit to your local industrial sewing machine vendor South West Sewing Machines in Houston. See if you get good vibes talking to them. Having a local resource for machines, parts, and service is a big deal. Shipping these little monsters across the country is not cheap.

As for screws, there is a mix of imperial, metric, and specialty xx/64 screws in many machines. Most Juki parts manuals, including the Juki TSC-441 Parts manual (Juki 441 parts List.pdf) list screw sizes, which is super useful. You don't want the screw material to be too strong. If you're going to cross thread or strip some threads, you want the screw to die, not the threaded hole. It's MUCH cheaper and MUCH easier to replace a screw than it is to re-drill and re-tap a threaded hole.

For the 441 class machines, the original Juki TSC-441 Engineer's Manual (Juki 441 Engineers Manual.pdf) manual is your best option. I see two references to alignment marks in the manual, both refer to the same area: Unfortunately, my Cowboy 4500 (a Juki TSC-441 clone manufactured by HighTex and sold in the USA under the Cowboy brand) ) does not have these timing marks:

Actually (and somewhat surprising to me,) currently neither Android nor Apple iOS have built-in image resize functionality (they both have cropping, but that's not the same.) I'm guessing both platforms do this on purpose to encourage app developers a to improve app store revenue streams. A simple, free Android app like Photo & Picture Resizer may be your best bet.

Let's also take a moment to appreciate that beautiful paint job on the Cobra Class 26 in Al Bane's video above.

Nice one, DC! I like the simplicity and the brassy steam punk look of it. A tight screw beats a magnet most of the time.

There is a video by Al Bane about the Cobra Class 26. Al Bane has some good videos but this isn't one of them. He make so many wrong statements that it's obvious he didn't do his homework before talking about this machine. But at least you can see what the machine looks like. Just don't believe most of what he says in this video.

On most machines the knee lift does not have a hold function. The hand-lift lever's first detent is the one you use during normal sewing. This first detent can usually be released again with the knee-lift. The hand lever will fall back down if knee lift raises the feet above first detent level, allowing you to have both hands on the material and lower the feet with your knee to start sewing again. On some machines the second detent does NOT automatically release when the knee lever is pressed. There's probably a good reason for that, but I can't think of it right now. Perhaps it's just for extra clearance when changing feet etc.

Good choice! The Cobra Class 26 appears to be a copy of the Juki LS-341 design, one of my favorite sewing machine designs. You should be in good hands with local support and expertise. I posted some image resizing instructions recently in this topic: I do wish the administrators would create a pinned topic or send new members some instructions on how to deal with image uploads in a welcome message. We have several instances every week with new members facing the image upload gauntlet. I found exactly one image of a Cobra Class 26 online. Cobra Class 26 Juki LS-341

Since this topic is sorta-kinda morphing into a show&tell of DIY magnetic edge guides, I started tinkering. I live near an IKEA and IKEA hacks are one of my favorite things. I made a magnetic edge guide based on an IKEA $9 GRUNDTAL magnetic knife rack bar and a small $4 BLANKETT handle (longer ones cost more). Each knife rack has twelve rare earth magnet bars glued to the back. The magnets can be removed carefully (the magnets are brittle, I broke one out of the twelve.) The BLANKETT handle comes in different lengths, has a low and a high guide edge and a nice, smooth anodized brush finish. The small version of the handle is just the right size for a set of three of the magnet bars and fits on the slide plate. I cut a longer handle to size to fit nine magnet bars for a stronger hold and longer guide edge. Simple double sided adhesive tape a or a few drops of glue will hold the magnets to the handles. The handles are big enough to grab with your fingers when pulling the guide off and the holding force can be adjusted by adding/removing magnets. I didn't spend quite enough time to scrape the glue residue off the magnets to make it look super pretty, but it's functional and can be made to look nice. I'm attaching a few pictures.

Yes, that is one example of the kind of machine you need. Those Juki LU-562 or 563 machine are great machines and this particular one looks to be in very nice condition.

If that's a criteria, you're better off skipping this particular machine. It's a cool sewing machine, actually, mainly because it's ancient and it says "Modern Age" right on it - how cool is that! But for sewing "pretty thick stuff" you really do need a proper industrial machine, not a sturdy domestic machine. Being a newbie is actually a really good reason to drop $1,500 on a very good new machine that does exactly what you want to do, from a reputable vendor (check the banner ads). Once you get get the hang of it, you can start gambling on vintage machines on Ebay or Craigslist for your second, third,etc. .... machine. Resistance is futile. As for that particular Ebay seller, I ordered one machine from them about two years ago and it wasn't really a good experience - missing parts, lots of grief and very poor packaging.

You can embed/link Youtube videos by copy/pasting the full Youtube URL into a post (the link you paste should look something like this https://www.youtube.com/watch?v=Z1QX4nL65L0 , not the abbreviated versions)

One way to get back to a reasonable starting pojnt is to turn the wheel towards you until the needle reaches the top of the material. Then loosen screw "A" to make both feet rest on top of the material. Then tighten screw '"A" again. That should bring things back into a normal state. The outer foot will start to lift up the moment the inner foot presses against something (material or feed dog). You need both feet and feed dog installed and ideally some material under the foot to check/adjust this. My Juki LU-563 adjustment video below shows this particular step at the 4-minute mark. The lever "B" gets actuated by an excenter that sits on the upper shaft inside the head. That excenter can (but very rarely needs to) be rotated on the shaft to change the timing of when arm "B" is being pushed out and pulled back in to create the up/down walking motion of the feet. I have yet to encounter a machine where that excenter needed adjustment. Keep in mind one of the main rules of sewing machine maintenance: Don't loosen a screw unless you know what it does. Here's the video I mentioned above (the equalizing of the walking foot lift shown at the 4-minute mark is one of the few things in the video that applies directly to the Singer 153W103):