Quade

I have a 211A I took apart and got back together. I might be able to help. I'll wait till you get the reverse lever thing straightened out. It took a bunch of adjusting to get the timing right. Mostly because the manuals are garbage.

I'd check ebay.

My 211 doesn't use a spring like that. Instead the spring hangs down from the top cover (near where the belt goes down) and hooks the reverse lever directly. If you absolutely can't find the correct spring, you could probably implement something like that.

There's a pin the goes from one side of the machine to the other. When the foot is lifted, a wedge pushes against the pin which presses on a lever on the back of the tension unit to release the tension. If you look on the back of the machine. To the left of the foot lift lever you should see a large diameter screw head. The pin is behind this head.

On that one, the top thread got cut on the first cycle or two then the rest of them finished the stitch. I just don't know what "right" is supposed to be. Comparing the cycles, the newer machine seems to turn a larger angle than the older machine. The old machine the hook seems to stop around 4 oclock, releasing the thread. On the new machine, the hook goes farther to 7 or 8.

It is supposed to cut the top thread every cycle? I have no idea how this is supposed to work but, it looks like the top thread is bring hooked, then cut at about 7 oclock.

I can confirm, at least in my 211A, when I pulled the hand wheel off the bearing came with it. It was quite a hassle pulling the wheel off too.

The video showed be a bunch. My theory about the linkage being wrong is wrong. That linkage is too simple to be wrong. I wonder if the eccentric, the thing on the main shaft that pushes the feed dogs has been rotated out of it's true position. If it's 180 degrees out, the feed dogs and needle bar will probably go backwards. It'll pull when it's supposed to push. I don't believe the timing belt being off will make it go backwards. It'll just mess up the "needle through the cloth" timing.

You should still look under it at the linkage I'm talking about. You still have the eccentric to set the stitch length. Without reverse, you'd be missing the middle shaft but, something is wrong between the eccentric and the shaft that moves the feed dogs/needle bar. Something about the linkage is making the feed dog and needle bar go backwards. I'd suggest posting a pic or movie of that lower linkage while you manually turn the hand wheel.

Does it have a reverse lever on the right? Is it up or down? I'd flip it up so you can look at the bottom. Turn the hand wheel in the correct direction and watch the eccentric which is about 1/2 way from the pulley to the hook on the main shaft. The eccentric drives the feed dogs and the movement of the needle bar through a relatively complex linkage. There's a shortish shaft between the main shaft (with the pulley) and the feed dog shaft (the top shaft if your machine is flipped up). This shaft is rotated by the reverse lever. I'd check to see if that shaft can rotate back and forth with the reverse lever. When the reverse lever is all the way up, it should move forward. With it all the way down, it'll move in reverse. You ought to be able to flip the linkage over by hand too. The eccentric is keyed to the main shaft. This eccentric is how the stitch length is set. If the presser foot lever is up, the outer foot won't go up and down. When the presser foot is down, it's the pushing down of the inner foot that lifts the outer foot.

Does this type work with thinner thread too? I wondered what the fiber washers were for. I guess they're like brake pads? For this to work, I'd think tensioner #2 would have to be pretty tight to keep the thread tightly in contact with the tensioner #3? Something about this system where the thread isn't squeezed but controlled by the rotation of the tensioner interests me.

Worker-B was close to $300. A decent servo motor with more power than the worker-B is about $150-200. It's hard to beat the Chinese. I'm thinking by the time you finish, it would be cheaper to just buy a Chinese servo. I have a Cutex branded one on one of my machines. It's been flawless.

Pics: I mounted the existing worker-B bracket to some aluminum extrusions which allowed me to adjust the position of the pulley pretty easily. The pulley can drive a belt if I was going to take it further, I'd machine off the plastic belt pulley part and install a larger aluminum one. This one is too small to grip the belt properly.

I'm working on a tangential project right now. I've acquired some Husqvarna early mostly metal sewing machines. Their first gen with stepper motors for needle position and stitch length. I'm using a raspberry Pi4 to drive the steppers and the main motor. So it's kind of what you're talking about. Using a 13 amp brushed motor driver and a PWM output from the PI I can control the speed of the main motor by pedal position. I might end up going pure stepper motor for the drive motor. In that way I can use the same driver for all 3 motors. These machines all have "Crank position" senors so it'll be possible to build in needle position without adding an additional sensor. Ultimately I want to be able to program my own stitches into the PI including bar tacks. It'll probably never be as compact as the purpose built Worker B controller. Once you see the pictures, you'll see 99% of the work behind the adapter. Getting it mounted to the machine was most of the effort. I took the pics, I just haven't offloaded them from my phone.

I installed a "worker B" on my singer 211. I used the singer pulley. I modified the stock worker B pulley to take a belt that would work on the singer pulley. It was successful, I could sew with it but, the motor and brackets were bulky enough they got in the way of tilting the machine back on the table. I'll try to post some pics when I get a chance. The worker-B motors runs on 90 volts DC. The controller controls the speed probably through PWM. It's only got two wires going to it so it's clearly not a stepper motor. The pedal is just a conventional 3 wire hookup to a 1/4" phono type jack. I'm using the pedal on another project now. I supply 3.3 volts to one leg, ground the other and I read the wiper with an ADC The magic happens in the controller. It converts line current to 90 volts DC, reads the pedal and sends the proper signal to the motor.