Constabulary

Jack servo shafts are straight.

Yes

Pulleys from Jack Servos are removable (I have two of em). The point is they do not supply smaller pulleys for this motor, so you have to modify a pulley with15mm straight bore. I guess thats why they say it is not removable. BTW why should it not be removable - some one assembled the motor and installed the pulley... so...

I made a sleeve for the shaft from 13mm aluminum tube with 1mm wall - easy task.

What kind / brand of motor do you have? A JACK servo from CS? They are removable but some have 13mm and some have 15mm shafts - guess how I know.

Its indeed a Class 17 but here are several subclasses.

Do you have a manual? Maybe this one gives you some answers. SD 28 Junker & Ruh Outsole stitcher Parts list and manual.pdf

Well, I´m on Ebay since... for ever... and never had really serious problems. A few smaller problems yes but nothing that really hurt me. They take money, yes, but that's business, right? So I´m not bashing Ebay here. I just wanted to give a hint regarding personal data settings which were unknown to me. I would guess Amazon is even worse - I almost never buy anything on amazon but that's another story.

Just found this site randomly (you have to log in of course): https://www.ebay.com/gdpr Site speaks for it self. But it´s of course up to you what you want to share or not. I opted out all of them now.

Cowboy / Hightex machines are sold by Frank Brunnet in Germany. You still can import them from Germany w/o paying Custom fees - this "may" end by the end of 2020 (but no one knows). https://hightex-germany.de/ https://naehmaschine-shop.com/naehmaschinen/

You did not say what needle size, needle tip and thread size you are using. Just from looking at the pictures and since almost all knots are flat on the bottom side I would suggest you try a needle 1 size larger or the bottom thread 1 size smaller. Or maybe reduce the bottom tension. Maybe you need a heavier beehive spring in your tension unit.

I had to google what an MBT thread #5 is - seems it is about 138 thread https://districtleathersupply.com/products/vinymo-mbt-size-5-0-6mm-polyester-thread-full-spool So for 138 thread you should use a needle size #22 or maybe #23 if the thread is thicker than 138 (see link)

The tone seems to be ROSEMARY, right? I cannot find it on my side of the pond - maybe DanishMan has more luck.

I haven´t seen any paint that is close to the brownish original Pfaff hammertone - at east on "our side" of the pond. If you want to use Hammerite (as a brand) I would probably choose gold. But you never know how good (how golden) it turns out at the end. So my preference is silver hammertone, that always looks good.

Where do you live? Helgoland, Uzbekistan, USA, Kamchatka, Australia, Falklands, Nowaja Semlja, Europe? Its easier to support you when you add your location to your profile. The Forum is very international.

I know that Adler 30 patcher are sometimes equipped with smaller 90Watt right angle gear motors and they er controlled by foot pedals as you find them on domestic machines. But they cost a lot more than a simple servo motor but they really work well but they have no brake. If you want to use a servo motor remove the accelerator unit from the bracket put a plain foot pedal on a wooden board and make a bracket for the accelerator unit and mount it onto the wooden board... ya know what I mean?

its a "quick change" slide plate for all kind of sewing devices / sewing guides. You find them more often on double needle machines than on single needle machine. You have no manual - look for a Singer 112w139 manual - should be a quite similar machine. Or maybe JUKI LUH-521.

As I said, I know JB weld very well and I´m using it A LOT (just as you do) - but keep in mind that you are threading the needle bar with a metal wire and the edges of the threading wire will wear off the epoxy sooner or later because it is "rubbing" exactly where the thread is running. So the groves in spring and needle bar are the result of the thread but also a result of the rubbing threading wire. I don´t think this tiny amount of epoxy will last for a long time. Just my 2 cents.

I know JB weld very well but I would not use epoxy on such a small "blemish". Not sure if it really would "stick" in place for a long time or how fast it will wear off again. How deep is it 0.2 mm? File it down - done. Really not a big deal.

I´m using heavy cast iron pedals too. My accelerator lever (JACK SERVO) has 2 notches for the spring, I simply set it to the grove further away from the pivot point - problem solved. If there is no 2nd grove just make one.

I do not know the output numbers. I´m "a bit" Singer crazy but I´m not really a historian. I know some facts but not really all details. I hope I can do the guided tour again one day. The tour guide said there are still old tunnels they have used for moving parts / machines between the different sections of the plant and they want to make them public one day - if possible (and safe). I have used an external picture host (https://postimages.org) and have linked the pictures here. That was the fastest and easiest way to post a large number of pictures and that way I could put them all in 1 post. BTW - found this picture on Wikipedia - seems it is pre 1928 because I cannot see the clock tower. Pic give a good impression of the size of the plant: https://de.wikipedia.org/wiki/Nähmaschinenwerk_Wittenberge#/media/Datei:Wittenberge_Singer-Nähmaschinenfabrik.jpg

It does but I think a skilled seamstress is faster. And you still need someone in front of the machine (whom you have to pay) who "feeds" the machine. Maybe you have less output rejects with this machine - maybe not... However - still a very impressive machine.

How about bookbinding board / grey board / pulp board / cardboard. You know what I mean? The material beer coasters are made of. I think its available in different densities but I´m not sure. If you have old books use the book covers. Thats a lot more environmentally friendly than foam sheets - I mean if you trash it anyway... just a random source: http://www.bmpaper.com/sale-10023646-chemical-pulp-raw-material-grey-board-sheets-1-5mm-cardboard-wrapping-paper.html

Patchers - they can be a lot of fun but even more a pain - sometimes. Ouuuuh yes, this little annoying thingy can be a pain and is the last thing you would think of. Not sure if it is mentioned in the manual but you can also move the needle holder a bit sideways (by loosening the upper screw) when the hook will not grab the thread. As Wiz said - you can also use 135x17 (or 135x16 for leather) they have the same length as the 29 needles but have a scarf above the needle eye. I´m using 135x16 / 135x17 needle only in my 29K71.

Imagine your opportunities.... smart home sewing machines.... ALEXA - sew that fxcking holster! I need it done when I´m back home. and there will be a day when you no longer can get updates (an parts) - hope there will be an XP mode then... ah well, maybe you can hot wire em. Will Ctrl-Alt-Delete work?