- ESC4P3
- Platen Punisher
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Re: New Drive Belt source for Smith Corona Electra 120??
Let us know how they work and how similar to the originals they seem.
- Kalani
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Re: New Drive Belt source for Smith Corona Electra 120??
Kalani wrote:
Yes. Definitely a difference between $10 for a belt and the SCM electrics need 2 belts, plus $10 shipping = $30, VS $15 plus shipping for a bag of 50 "O" rings from McMaster.
Thanks for the link. I'll try a pair.
k
I noticed that the rubber "O" ring type of "belt substitutions" are leaving a black residue on the pulleys. And, wondering if there's any slippage that causes the power roller to not speed up or torque as well as with the OEM "V" belts.
I just ordered 3 pairs of these "V" belt close to OEM types. I'll try them out on a SCM 120, and a few others and see if there's a noticeable performance difference that would make the higher price worth paying.
Will keep you posted when I install them and try them out.
k
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Thread Starter- Kalani
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Re: New Drive Belt source for Smith Corona Electra 120??
Jim, I finally got the order in for the Gates Polyflex belts per the link you gave. They were too tight for an Smith Corona Electra 120. The "O" rings were a bit more stretchy and forgiving for small size differences between machines.
I found a good fit for the Polyflex Belts on this 60's Series 6 Smith Corona Coronet Electric. They were a little on the tight side but still fit. You can see the large gap between the back motor belt and the carriage trim body plate. But, ran well, no vibration, and pretty quiet. Should last a lot longer than the O rings I think.
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Thread Starter- OregonJim
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Re: New Drive Belt source for Smith Corona Electra 120??
Two ideas come to mind:
1.) Loosen the motor mounting bolts and see if you can nudge the motor a couple of millimeters forward. I suspect that this is how the factory adjusted for variance in tolerances.
-or-
2.) Try a 3M320 belt (3mm x 320mm) instead of the 3M315 (3mm x 315mm).
Either way, thanks for taking the time to share your experimentation!
- Pete E.
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Re: New Drive Belt source for Smith Corona Electra 120??
Is that usual for a v-belt to have "teeth" along its outer surface ?
- M. Höhne
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Re: New Drive Belt source for Smith Corona Electra 120??
It's pretty clearly mounted inside out.
- Pete E.
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Re: New Drive Belt source for Smith Corona Electra 120??
Hi iMichael,
I was thinking that as well...but a zoom-in on one of the photos seems to show the traditional v-shape with a flat bottom to the v in the photo blow up...
.
- skywatcher
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Re: New Drive Belt source for Smith Corona Electra 120??
Hi Pete and Michael
Externally cogged V-belts are quite common in the lawn and garden equipment industry, especially where a small belt has to carry a heavier load. An externally cogged belt has better flexibility for conforming to smaller radius pulleys. I see these externally cogged belts quite often in my line of work. I've also heard it said that the increased surface area of the back of the belt helps to dissipate heat better, although I don't think that overheating of these belts would be much of an issue. All the best
Sky
We humans go through many computers in our lives, but in their lives, typewriters go through many of us.
In that way, they’re like violins, like ancestral swords. So I use mine with honor and treat them with respect.
I try to leave them in better condition than I met them. I am not their first user, nor will I be their last.
Frederic S. Durbin. (Typewriter mania and the modern writer)
- OregonJim
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Re: New Drive Belt source for Smith Corona Electra 120??
What Sky said - the average thickness of the belt is increased while still allowing it to bend around a tight radius without cracking (and it also dissipates more heat). I've seen them used in industrial-grade printers which run at high speed/torque with relatively small pulleys.
- Pete E.
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Re: New Drive Belt source for Smith Corona Electra 120??
William and Jim,
Thanks for your additional info.
I have a new-to-me S-C 250 electric machine on my work bench this week. Will try some of these externally cogged v-belts.
This 250 has that 2-speed motor set up...yet the power return is not quite the battering-ram I was expecting. Surprisingly on the more tame-side.
.
