Making a Cleated Belt

[francist]

I Believe that they use the same type of belt, not sure that they would fit.

You are correct, the Supermatic (I have three) does use a cleated cord belt as well although they employ the more common wire style of cleat. Here’s a picture of one hiding just behind the cam…



I don’t know about the spacing and it may be quite close although there’s also the problem of hitting exactly the right belt length too — there is no adjustment room. I have seen wire cleated belts that use two and sometimes three wire cleats side-by-side (my Singer 306, for example) to obtain a wider cleat and that option did cross my mind as well. I just ended up showing more promise with the flat aluminum material over my wire experiments so I went with it. This is double-cleat cord belt for a Pfaff…



The original Turissa belts were very contemporary in appearance — they look just like a synchronous belt you’d buy today — just that the pitch seems to not be common anymore. As for the material they were made from though, that’s an interesting question given how they seem to self-destruct after 60 years or so. That said, I have seen an original Turissa belt of the cord style too, so it looks like there were a couple variations possibly depending on the year. Here’s a couple photos of original Turissa belts still in place as well as another NOS replacement one that is supposedly available for purchase in Finland. It’s worth noting that one of the co-founders behind the Turissa was Fritz Gegauf of Bernina reputation. You can see a lot of similarities to Bernina as well as Elna in the Turissa.





One last photo — this is the belt from the 1950’s IBM typewriter I scrapped a while ago. It fit the Turissa pulley perfectly but was about an inch too small in diameter. Dang!



-frank

 

[C-Bag]

One last photo — this is the belt from the 1950’s IBM typewriter I scrapped a while ago. It fit the Turissa pulley perfectly but was about an inch too small in diameter. Dang!

I HATE when that happens.

 

[great white]

Singer, pfaff and many other older machines use the cleated belts. They’re actually fairly common on (older) industrial machines. The Singer 111w comes to mind.

my Singer 319 uses a cleated timing belt. They also now make rubber cleated timing belts for the old cloth and metal cleat belts.

The timing belt on my 319 was fine, but I ordered a new rubber belt and it works wonderfully. I wanted to save the fibre belt, so switched to the rubber. You usually can order the belts bu width and cleat count. Not cheap though, count on dropping around a hundred bucks if you go down that route….

 

[francist]

Part 3 — Closing the Loop

Thought I’d close the loop on this venture and let you know how it all worked out.

I had anticipated more work yet to be done on the motor drive pulleys but I figured I’d see how bad they were before thinking about how to make new ones. For those familiar with the drive system in the old Elnas, the Turissa system is much the same albeit with a less complicated shape. The motor shaft is fitted with a small rubber wheel which in turn presses against the face of a larger metal wheel on the machine shaft. The small wheel on the motor drives the larger wheel on the machine shaft purely through friction.

This works fine but the small drive pulleys are notorious for getting less grippy with time or developing a flat side from long periods of of inactivity. The result is usually spinning and screaming tires or rough and rumbly operation. So when I mounted the motor back in to test the new belt I was surprised that the wheels still drive quite nicely. The upper one is a bit worn (it supplies the main shaft power) but the bottom wheel (only used for the bobbin winder) is still in really good shape.






I have to say I like this system better than the Elna — the rubber tires are simpler; there are two instead of just one for both functions; and you can position the motor at rest with neither wheel contacting their driving mate so they’re much less likely to develop flat sides. Plus they’re held on with a simple set screw instead of a dinky little split pin that needs a special extractor tool to remove. I think I will probably go ahead and plan to make a couple new ones just because they’re a pretty simple design.

Anyway, enough wind-bagging, here’s a short clip of the Turissa running…

View attachment IMG_1905.MOV


…and I also put one here with a few more pieces back on the machine…

https://www.hobby-machinist.com/gallery/turissa-ultramatic-2nd-run-test.98218/

But of course the real question — does it stitch? Yup, it would appear so…





Thanks for looking!

-frank

Oh, if you want to check back on the Elna drive wheels I did a short blurb on them here…
Post in thread '2021 POTD Thread Archive'
https://www.hobby-machinist.com/threads/2021-potd-thread-archive.103242/post-900795

 

[silence dogood]

Frank, that machine purrs like a kitten. About a year ago, my wife got a Pfaff 130 with an added embroidery unit. That thing is built like a tiger tank and runs like it was brand new. Need to make a table to mount it in.

 

[francist]

Ooh nice, I’d love a 130. It’s high on my list but they’re not easy to come by around here. Fingers crossed…

-f