nejcek74

Aren't that those the parts?

yes, that's right, both machines were only fixed/sitting on those rubber feet.

I have few old US machines, like 52900 and 53100. They are not in use at the time, as of lack of space :)))) Here is a pictures of the original table. At least for those two machines the tables are the same. They are very finely engineered, with pre-made holes for rubber fits, hinged access for the machine etc, lower board that can be fine tuned into the position etc. For sure made with a rig in a factory. For a single use I would do it much simpler. Ok, I would have to do it much simpler, as I don't have necessary machines :))))

I think the machine was produced till late fifties. Similar knob was also used in 238 but not in later 438. Such parts are not available any more, if you are lucky you can find sometimes something on ebay. Otherwise, just glue it together. I did this with the one I stupidly broke when cleaning the machine.

On my machine (Pfaff) you set the needle into the centre of needle hole in the feed dog by moving the needle bar frame. This is the upper assembly that includes needle bar and upper feed mechanism. By my machines is always annoying to get some movements. How is this solved by Juki I rerally don't know. check on which axe the needle bar is hanging, is there and screw that you can loose, and than by rocking the wheel you push the whole assembly slightly to the left.

In my opinion 1000$ for a machine that is so old is way too much. I own old pfaffs and Adlers, but I am using them as hobbiest and with a lot of love for old iron. It's great machine with some limitations (small bobbin), but with limited documentation and limited access to parts which are often very expensive. The worth of the head is max 300$, 500 if you really want this machine. Tables and old motors are practically not worth much.

Google for parts diagram of the pfaff 545. Find the other post here for pfaff 545 and also 1245. Others, including me we already wrote and linked a lot of info how to time it. Feet will be the same as for 1245. Same is for hook and bobbin case, but you need to choose the right one according to your subclass (H3). 0) check this forum, 99% is already here 1) get parts diagram and find missing parts 2) compare it to 1245 to find some equivalents. 3) go to ebay/amazon /Aliexpress and get what you can 4) if something is still missing you will have to do more research 5) use pfaff 1245 engineering manual for timing it 6) ask here for what is missing

Your timing is a little bit off (hook should be at the needle scarf when already on the way up, distance is defined in the manual) and probably the needle is too far from the hook (it should almost touch the needle, but not exactly, ca 0.1mm). I suggest you to find the engineering manual and follow it to time your machine.

I bought it here, it's both needle bar clamp and gauge: https://www.diamondneedle.com/timing-gauge-set-p:11618.html

I have few pfaffs in the range of 142 to 1245 and I always adjust needle bar height regarding to the hook. - get the needle bar into the lowest position - advance so the needle bar rises to the necessary height regarding the model (between 1.6 - 2.5 mm)* * first I was doing this with making a black mark on the needle bar, later I bough the clamps for that - in this position the top of the needle hole must be 1 mm bellow the hook point see pages 9-10 here in the attached manual. Whenever I had serious problems I followed the manual from the beginning to the end and it always helped. p.s. manuals sold on the internet are usual exactly the same as the free one. Pfaff 1245 Adjustment 89_09.pdf

To me there are a lot of visual similarities with Pfaff 461 (or 463, 467, or 483 etc) or something from that era and source. But they were all fast straight stitch sewing machines for light to medium fabric.

At extremely low speeds the power of the motor is extremely low, so there is no point to engineer a motor that would be extremely powerful to overcome that. It's better to use a different gear ratio. In the production operators are skilled, and speeds are high. With a combination of needle positioner and other automatic controls low speeds are even less needed. Outside of repairing stuff and hobby users there is not much need for such motors, we should be lucky for that what we have :))))

My moderately priced servo has 100 rpm minimum speed has some shaping on the case, but not exactly cooling fans. Efka DC 1600 that I had to remove because of dead control box is completely different beast, 2 the size and weight, cooling fan etc.

I guess the problem is with the minimum speed to start. Which is I guess an engineering characteristic of the motor, but this is beyond my limited knowledge of electric motors Regarding torque of different types of motor I found this:

of course they have, this is from Efka site: which shows that torque is more or less flat in the lower part of the rpm. It also shows that they have two different servos, one built for speed and the other built for torque. The power is function of speed and torque: P [kW] = (T [Nm] · ω [rad/s]) / 1000 in lower speeds where torque curve is flat the power is increasing constantly with speed. Later it can decrease slightly (depends on the turning curve of torque). Of course when the speed is 0, power is also 0. And because of engineering reasons the motors have minimum speed at which they work.