trash treasure

Looks like it's missing the presser foot leaf spring - One from a Singer 7 would probably work.

If you're using a decent bonded thread, then a #22 should normally be OK with V92, but maybe on that heavy of a stack, I might try a 23 - Can't hurt to try. But I'm also thinking you have a burr somewhere - Maybe in the foot needle hole, or the plate, or the hook. I grind them out with a dremel tool and diamond burrs, and finish polish with one of those little rubberized abrasive points. We use mostly Organ Titanium needles for sail work - They seem to have a little less of a problem with seam-stick tape, but that's a different subject :~)

Is the belt between the top and bottom shafts intact ? No feed, if that belt's broken or stripped ....

Thank you, Wiz - Sailrite is all about marketing to amateur DIY's - That has always been their main thrust, and most professional sailmakers shop elsewhere for their supplies. Although they DO offer some professional services, those are in the background, and you don't see them advertised. This forum, on the other hand, is all about knowledge, and the information needed to use this heavy duty sewing equipment, new or used. I think most vendors here assume that, as a customer, you're already on a level where you know what you want to do, and don't need to be "marketed" to. That doesn't mean they won't help if you need info - They're just not expecting to need to spoon feed it, as Sailrite does.

It looks like a Singer 188 of some variety - They came in a couple variations, some with a built in bobbin winder. Light / med duty, straight stitch, tailoring machine, I believe.

Singer 7 class? Interesting stand - Looks like something for some kind of machine tool ....

Auto parts stores might not have a belt of that small a cross section, but any industrial supplier will have one - I use McMaster Carr. The belt size you need is called a "3L" - Just measure the length of the old one, or around the outside of the pulleys.

What's been said before - A rotary phase converter large enough run both machines, or change over to individual single phase servo motors. A VFD won't work here. Just changing over to single phase motors probably makes the most sense economically.

As it's a used machine, check to make sure the timing stays the same in reverse - There's an adjustment for it, but check to be sure. It's visually obvious, if it's out, by watching the needle / hook relationship in forward and reverse - It drove me crazy on my 167, before I figured out how to fix it.

Someone sawed off your toe : https://www.cutexsewingsupplies.com/search?variant=32221836935221

I don't know if I can help, as I'm not familiar with that model - Does your machine have a differential feed, and if so, have you tried adjusting it to see if it changes the issue? Are the knives sharp and set right (Lower one even with the needle plate)? Feed dogs tight & level with needle plate? Presser foot down all the way and set correctly? Are the loopers clear, and not jammed up with trimmings ? One or more tensions way out of whack ? A lot of things to cause problems with a serger - Start with fresh sharp knives, first, and a different color thread in every spool.

I just checked an Adler 167, a Singer 111, a Singer 153, and a Singer 211, and the outer foot contacts the feed dog on all of them - When you look at the feeding action, the outer foot is lifting as the inner foot and feed dog are moving, so it's all good :~)

Cheap 20U zig zag copy......

Success ! I followed Michiel's suggestion to adjust the upper arm eccentric, and it worked 100% - The timing now stays exactly the same, forward and reverse. I did find that I also had to adjust the feed dog lift eccentric under the bed, to bring the feed dog back up to proper level, after the stitch timing was correct, but now the machine sews PERFECTLY, forward, reverse, at any speed, with any material thickness - Thanks again !

Thank you, Michiel ! I have the same problem with a 167 (Timing changes in reverse) , and it's been driving me nuts - Now maybe I have the answer :~)

That's very interesting - What kind of lathe? Do you use it in the bearings (and if so, are they plain or ball / roller?), or just on the ways? I use tractor type hydraulic oil for my lathes, for the same reasons - I hate the smell of the Mobil Vactra way oil, that you're "supposed' to use. Tom, apologizing, for going off topic......

A most colorful shop, Garyak :~)

HA ! Just goes to show - You can't believe everything you read ;~)

One other thing about the 20U - They were never really factory machines, being sold mainly for tailoring use, so you usually find them in pretty nice shape, and not worn out from 3 shift, 24 / 7 type use and abuse.

As Wiz said, the 20U is an all purpose machine - The one we have has proved excellent for many years.

I see Singer 20U's pop up for sale on FB Marketplace pretty often, and often pretty cheap - A decent machine, if you don't need something really heavy duty. Better to look for a BLUE one, though, as those are made in Japan - The Gold ones are Chinese manufacture, I believe.

I like the brushless servos so much, that I even use a 750w one to power a small metal lathe - It'll take a .030" cut in mild steel without slowing down. Probably voided the warranty, though

Whatever it is, it looks like it would have been very useful for a job or two we've had

Most excellent! That's a fine machine - You'll have many years of use from it.

Here's the parts list: https://www.universalsewing.com/images2/parts_lists/all/aokko5oe.pdf If you mean the little hooks that pin into the rear of the bed, the part number is 91-029 450-15 . They're all the way down on pg. 22