nejcek74

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.

here is the old adjustment manual Pfaff 1245 Adjustment 89_09.pdf and parts list Pfaff 1245 Parts 85_07.pdf actually I gave you up the relevant information for the old 1245. If you are unsure which subclass you have please make a photo of the shield with class / subclass and share it here. It's kind of hard guessing things with so little information from your side :))))

Just for info, certain old casting Pfaff 1245 are using needle system 190. OP will have to check his machine, which subtype is and if it was maybe adapted for something else. My Pfaff 1245/48 that I bought used came with needles of the system 134. At that time the needle bar in the lowest position was pressing down on the presser foot if it was raised. I changed it to 134-35 as I had them at the time and it is just barely long enough that the parts are not touching.

If he is using Pfaff parts, maybe this is a copy of Pfaff 335? Which was often sold as a binding machine. Regarding 2-way (only horizontal) vs 4-way (horizontal and vertical) feed dog movement there was already written a lot about it on this forum. Conversion is possible but it's a mayor work because you need to connect the upper shaft with the lower one that moves the feed dog. You also need parts which are often more expensive than an used machine. My Pfaff 1245 has only 2-way feed dog and it works for me perfectly fine, but I am using it mostly for heavy fabric or combination of heavy fabric and leather. I guess certain, very fine surfaces could be scratched by a feed dog dragging back.

I learnt sewing with modern servo motor with needle positioner. I am buying them in Europe from a big reseller, Strima, they are around 300 euros. They start at 100 rpm minimumspeed I think, 750 we. Thanks to needle positioner I don't miss lower speeds. I do needle up, needle down and I can go step by step when I want. And the needle is always in the right position (locked stitch or open tensioner etc) so working is easy and precise. I don't need and don't want a speed reducer under the table. A jog dial would be useful to limit upper speed which I need to do on the controller. I also miss more robust needle positioner with better and easier fixing to different types of machines. For me a middle priced servos with good documentation and support would be interesting. Efkas prices are too steep, the cheapest Chinese imports are undocumented and have often strange quirks that are difficult to solve

Yes, it looks like there is no positioner. One of my similar low cost servos didn't operate without positioner, even when the function was switched off in the menu :))) I checked his video again and actually it looks that the white pin operates as intended. Or so I guess.

Plastic white pin is for back-pedal. for normal sewing you press the pedal down and the motor starts, the more you press the faster it spins for back pedal you press with the heel, pedal moves up. In my case it is used to put the needle in the up position (used togetehr with needle positioner). While starting / sewing the plastic pin should rest in the lower position. Only when you back-pedal the plastic pin is pushed up. I guess here could be your problem. Adjust your pedal and the rod.

Here is the adjusting manual: https://www.duerkopp-adler.com/fileadmin/dag/Media/Downloads/205/S_204_EN.pdf and a previous topic on the forum linking to Uwe's videos about the machine. I guess that was the video you were following for adjustment? If not, check it. My personal experience: I am still learning adjusting the machine, but I found always the best way to meticulously follow the adjustment manual. No shortcuts. Sometimes I need to repeat the adjusting process few times, maybe something slipped, I did something to tight or too loose or I misunderstood the description. But at the end is always fine and after few repetitions I am already efficient.