Singer 111w155 feed lift eccentric - balance wheel?'s

[Wyowally]

I got a lot of help here with my original list of questions. I'm down to trying to understand this eccentric and it's design, parts, and operation. I've seen the picture of the grooved interior on Superior's catalog. I've fiddled with mine, and not knowing anything have been able to change lift somewhat for both feet. Read the manuals and looked at the illustrations. On mine, it appears there is a blank hole, then a threaded hole with no screw, a smaller headed screw just below the larger headed worm screw. Thinking I need a set screw in that empty threaded hole. When I loosen the smaller screw the whole eccentric spins on the shaft. I can change lift (unpredictably) by turning the large screw. Somewhat. The large screw will also turn with the set screw tight but not sure it changes anything. A description of how this works mechanically would be great! I'm thinking one screw should hold it on the shaft and stay tight, the other screw loosens the two pieces of the eccentric so the one with the worm threading can move or act as a stop for adjusting. I might be over-thinking.

I'm loving this and thinking about a total restore. The paint on the inside of the balance wheel is flaky, but no luck so far with those set screws. Done overnight PB Blaster and some heat so far, custom ground a long reach screwdriver tip. Don't have to do it, just want to. Help appreciated!

[Uwe]

You’ll have to show us some pictures of the parts you’re talking about. Your words don’t really match what I’m picturing in my head.

[Wyowally]

Pictures tomorrow Uwe. This thread: Presser Lift Eccentric Assembly/Disassembly help need Singer 211G165 - Leather Sewing Machines - Leatherworker.net is about a similar problem on a 211G165. That eccentric has a collar and spring which the 111w155 does not - a feature evidently borrowed from the stitch length eccentric. I'm not desperate - my feet are lifting equally almost 1/4" now.

[Wyowally]

Singer part number 240744 as in this illustration from the Singer parts book:

[Uwe]

Which parts book is that page taken from? Do you have a link to the whole parts book? I don’t remember ever seeing that mechanism on a Singer 111W155. I’ve seen it on other machines.

The position of the slider on that eccentric determines the eccentric offset - the distance between the center of the driving shaft and the center of the collar bushing. That offset determines the amplitude of the eccentric motion, meaning how much or how little the connecting rod moves (wobbles) as the mechanism spins. 

The worm gear is used to change the position of the slider. As with most worm gear designs, the purpose usually is that the worm gear can move the slider, but the slider cannot move the worm gear. Rotating the worm gear moves the slider, but pushing on the slider does not rotate the worm gear. This prevents the slider position from changing on its own as you sew. There’s probably a locking screw that fixes the slider in position and takes slack out of the mechanism to minimize noise.

I’m curious to know if your Singer 111W155 is a special version of some sort to employ this eccentric mechanism for walking foot lift. The standard 111W155 foot lift eccentric has a fixed-offset eccentric and the motion amplitude is then changed by changing the position of the connecting rod on the “banana slot” in the driving lever.

I’m looking forward to seeing some photos of your machine and that eccentric detail.

 

Edited May 7, 2021 by Uwe

[Wyowally]

Uwe - the old parts book copy from Superior SM Co.. I'll try to attach it here. One of the military manuals also explains that models for a number of years are like mine and the adjustable eccentric was standard. The eccentrics are still sold and available. Then later Singer changed to the banana slot. Mine isn't a special version, just older than what what you've seen. The parts book illustration shows the unit pretty well. I'm still researching. Parts book is too big, won't attach.https://www.supsew.com/download/Singer/Singer 111W155.pdf

[DonInReno]

On 5/6/2021 at 6:34 AM, Wyowally said:

no luck so far with those set screws

It’s quite impressive how tight some screws are.    The small slot on those set screws makes a properly fitting screwdriver important.  I keep two Klein electrician screwdrivers handy for those set screws - the tips are quite hard and fit the slot well.   One is just a normal screwdriver.  The second is essentially just the metal shank of the same screwdriver and it gets struck with a hammer, metal-on-metal, to help jar the set screw.   
 

On very tight screws I normally smack the set screw sharply a few times, which is probably only increasing the indent in the shaft a few ten-thousands, but it does release some tension.  Then the area is heated up to at least 175 degrees, which frees up any resistance caused by dried oil or other substances acting as a thread locker.   The handwheel bore will also increase in size slightly - the bore of a steel hub expands about .0007” per inch per 100 degrees.   Since it’s only a 1/2” bore, it only grows a few ten-thousands, but it still helps.

Hopefully nobody has tried to turn those screws with a poorly fitting screwdriver and buggered up the slot.  In those cases you might try one of those impact-actuated screwdrivers....finding a hex drive screwdriver bit of the correct size would take a bit of looking around.

Edited May 8, 2021 by DonInReno

[Wyowally]

Don - the screws came out using my custom ground screwdriver tip - after soaking with my mixture of chemicals. The wheel also came off easily, tapping near the hub with a plastic body hammer. All I wanted to do was paint the inside of the wheel!  I have used all the methods you outlined except the impact jack hammer you illustrated. One thing I use not mentioned is called an embossing heat gun.  They are just a miniature heat gun, sort of like the hot air version of a mini torch and handy for small places.

Thanks for following up. I'm getting ready to paint it. Trying to decide whether to go shiny black with decals or industrial wrinkley.

[DonInReno]

I’d love to have one of those embossing heat guns!   Maybe Santa will put one under the tree!
 

There is something extra nice about a super high gloss black machine with bright fresh decals, but that can be a lot of work to detail.  I made the mistake of stripping the paint and filler off a 111w and it will take 20 hours of filling and hand sanding to get it as straight and smooth as it was - it may go back to a hammered finish.   
 

I’ve always been impressed with those who have been able to make money stripping and refinishing sewing machines.   I’d make more money per hour working for minimum wage.   Lol

Uwe turned me on to these silicon plugs used in powder coating to keep holes clean.   They work great to keep paint out of the various holes and whatnot. 

Edited May 8, 2021 by DonInReno

[Wyowally]

Don,

I've been priming, painting, and decal setting. I didn't have the plugs, but have lot's of foam in different densities. That's what I used and it was easy to stuff in the holes. Almost done, a few things to go.

[DonInReno]

Looks good!

[Wyowally]

Decals on....

[Wizcrafts]

4 hours ago, Wyowally said:

Decals on....

Oooooooo!