Constabulary

I would try some turns on some scrap leather to figure this because different machines may act differently due to sightly different settings, needle thread combination and so forth. BTW If it was me I would use a shorter stitch length on a project like yours. But that's just me.

The 29K51 has a lot in common with the later 29K71 but the gear box is completely different and the pinions are no longer available. The 29K51 has a "drop out" gear box. The 29K71 manual and parts list is very helpful but as said it has a different gear box. I also have a German language Manual if you want it let me know

The old Singer parts are of better quality than new generic parts from China IMO. I repaired some tension units (making one out of two) a while ago. I hammered out the stud from the rear. I think you can get replacement studs from College Sewing. Just check the parts list of your machine and check the number on the College sewing website. I would also order some spare screws for the feed dog, Needle bar, needle plate... Maybe some bobbins lint brush... they have everything.

Check the below attached parts list and note the sentence "THIS MACHINE IS THE SAME AS 29K1 WITH THE FOLLOWING EXCEPTIONS:" The 29K1 is the basic machine and the other subclasses just have some small differences. 29 and and 29K are the same machine. The 29 are US made and the 29K UK made and the parts are interchangeable. The ancient 29 / 29K just differ in the accessories but the basic machines are the same. F.I. front wheel or side wheel, presence of a wax pot or not, different needle plates... I once restored a 29K1 https://leatherworker.net/forum/topic/60554-29k1-pre-christmas-barn-find/ You can modify the modern Singer 29 / 29K bell crank levers. Most parts are no longer available for the old 29K models and do not expect that modern 29K parts (as for 29K51 or 29K71) will work for the ancient 29 / 29K machines, some do but most don`t. 29K1 TO K4,K10 TO K18,K12 TO K23,K30 TO K33.pdf

Here is a free English language Junker & Ruh SD28 Manual. The Pedersen 308 is the same machine. SD 28 Junker & Ruh Outsole stitcher Parts list and manual.pdf

Are you talking about triple feed machines? If yes, then Adler, Pfaff and Singer have their own foot system but a lot of modern clones are using the Singer foot system. So depending on the machine model it is very likely that Consew, Seiko, Juki, Mitsubishi, Brother are using the "Singer 111! foot system. But again - it depends on the machine model.

When the needle - hook timing was right at your machine and it worked properly with this setting and when your new needle bar is in you have to adjust the needle bar height. The procedure is mentioned in the manual on Page 14. Does not matter what needle system you are using, the procedure is the same. 51W51,W52,W53-Inst.pdf

This video by LW member UWE may be helpful for you:

You are welcome BTW - toothed V-belts are better when you go around small size pulleys.

Back then I had no proper size V belt for the test setup. But yes, it actually works.

I forgot this picture:

Not sure what he used but cheap pillow blocks for 15mm shafts can be found on Ebay F.I. Pillow Block Type KP002 https://www.ebay.com/itm/144782907792 a 40mm and 120mm pulley (for 1:3 reduction) with 15mm bore can be found here: https://www.ebay.com/itm/264553616997 15mm shaft: https://www.ebay.com/itm/163869249505?var=463451784748 Just some suggestions I have used these bits for some speed reducers and I´m running one with the above components on my Singer 51w post bed machine. I just have the reducer in a different position. Depends on your stand where you mount it. This is just how I did it. EDIT: You may find the bits cheaper if you dig deeper but smallest pulley here is 45mm https://www.ebay.com/itm/272680918308

If it was my machine I would replace the entire clutch. I think that will prevent you from headaches. The safety clutch AFAIK is the same as on the Singer 111 machines and they are still made today: https://www.ebay.com/itm/142979170694

Looks like the 650W motors are gone already but here is one for less that 80€ (if they do not change the price). https://www.ebay.de/itm/285271068358 Not too bad I think.

Please post pictures of your machine. Assuming you have the 2nd (later) model of the Singer 51w. This may be helpful for you: I once converted the needle bar at an early 51w model. May be interesting for you as well - or maybe not

Just another option: https://www.ebay.de/itm/404312815806

@Landersohn I would check the Singer Class 7 Manuals cause the upper head section looks very similar. Hope that helps.

I once owned a 105MO but that was quite some years ago. MO means it was meant for sewing Moccasins. IIRC it has an independent top and bottom feed and IIRC (again) it was tricky to match up top and bottom feed. EDIT: Some technical data form a leaflet but the complete file is too big to upload here. Send me your email address by a PM so I can send some more files.

There for sure there is a way. You have to change out certain parts (compare the parts lists of the H3 & H4) BUT I´m not sure if all the parts are still available and Pfaff OEM parts are super expensive. But most likely it will not be worth the money / trouble (my opinion). Maybe it is just the foot lifting lever and two or three other bits but I do not know for sure. You have to compare the parts lists.

Basically ALL 145 can sew leather it just depends on what leather thickness you want to sew and with what thread size. Keep in mind, the tag on the machine just says in what setup the machine once left the factory. It is well possible that it was been technically modified (up or downgraded for certain applications...) over the years maybe once, twice...

29K´s are not all the same - they may look quite similar but there are several technical differences. Which 29K do you have - the number after the K is quite important. F.I. - I have restored a 29K1: and a 29K71

you can try parts of a Seiko TF-6. They are "clones" of the Singer 18 but I´m not sure if the race is the same on wheel feed machines.

Kwokhing / KH Sew is a top quality manufacturer from HongKong (China). Not sure who offers their products in the US but you can buy either directly from them or f.i. College Sewing in the UK sell their products too. Sometimes you even find them on Ebay. The parts are usually marked with their distinctive KH logo. But their presser feet are more expensive that the no name feet from Ebay / Amazon but less expensive than Pfaff OEM.

It´s overall not too bad it was just stored under bad conditions for a long time. The underside is very nice - just old dried oil and some dust. I´m a little between the chairs but I think I will repaint it IF it will sew properly. Maybe hammer tone silver and black flat bed.

Found one in my part bins that works. Not sure what the Singer part number is but this one with # 52394 on Ebay looks quite close (just in case some one is looking for one): https://www.ebay.co.uk/itm/385661563974