8mm Forum: Elmo: v-shaped belts vs round belts

This is topic Elmo: v-shaped belts vs round belts in forum 8mm Forum at 8mm Forum.

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Posted by Adrian Winchester (Member # 248) on January 31, 2015, 11:37 AM:

I while back I bought an Elmo ST-180 on eBay, to give my GS a rest when I didn't need more light on a large screen. It was a good buy for £100 because it was genuinely like new in the original box and had been bought in relation to a film-making project that had never happened. It's also a relatively 'young' early 1990s projector, when this was probably the only non-telecine Super 8 projector that Elmo were still making.

So, the projector has no wear whatsoever but I bought new belts as the motor belt was stretched and loose. The projector now works fine except the take up spool stops now and again (especially if you stop it briefly by hand) although it then seems OK when you next start the projector. I wondered if the reason might be that the replacement belt I bought, although sold "for" the ST-180, is a normal round type unlike the original v-shaped type, which I'd imagine provides better grip? If anyone thinks that might be the problem, I don't suppose the original type is still made by anyone? If we have to settle for round belts, I expect some of the ones sold are somewhat approximate in terms of the tension, so I'd appreciate any recommendations in terms of ones that people consider good.

I've cleaned the belt to ensure that it isn't at all greasy and I might try applying some 'belt grip' that I have in an aerosol.

[ January 31, 2015, 10:57 PM: Message edited by: Adrian Winchester ]

Posted by Mark Todd (Member # 96) on January 31, 2015, 03:01 PM:

Hi Adrian the round belts tend to work better on the motor though you may need to adjust the 24fps pot in the back. The origional motorbelt is a sort of V shape but they tend to oscillate around and can catch the shutter getting quite noisey as well.

Take up wise the round ones are usually OK, but you can get the sqaure ones still here and there.

Best Mark.

Posted by Adrian Winchester (Member # 248) on January 31, 2015, 11:13 PM:

Mark - thanks for the reply, which caused me to edit my message as I'd forgotten the belt was V-shaped rather than square. It's interesting that you say these belts can "oscillate around" and be noisy as I had that problem with a ST-600 I used to own, which I expect takes the same belts. At the time, I wondered if something wasn't lined up quite right, but if this is a common problem, perhaps those belts were a bad design idea, even if they sometimes worked OK.

Regarding "you may need to adjust the 24fps pot", are you saying that using a round belt might cause the projector to run at slightly different speed?

Posted by Mark Todd (Member # 96) on February 01, 2015, 02:35 PM:

Hi Adrian, yes the round main motor belt you may need to adjust the 2 potemeters with the little slots in the back, I forget which is 18 and which 24, but someone will know.

The main motor V belts are very prone to twanging about a bit and a bit more noisey too when they hit the fan so a round one is far better. Sometimes they can only just just catch the shutter blades and have you scratching your head wondering what the noise is etc.

All the 600 range of machines the film drags after about 200 feet in the channel after the 2nd sprocket so worth doing something to stop it touching down in the film path there.

Best Mark.

Posted by Tom Photiou (Member # 130) on February 01, 2015, 02:57 PM:

Many of the Elmo ranges were made with v section pulleys to take the V or square sectioned belts so they fit into all the pulleys properly, if they jump about or vibrate then they are worn and should be replaced, they become stretched & will also cause drag on the take up or wow and flutter The round ones do the job just fine but wont sit all the way in, any speed variation would be so minor most people wouldn't notice. [Wink]

Posted by Adrian Winchester (Member # 248) on February 01, 2015, 05:17 PM:

Tom - I must say that when I had the problem with V shaped belts, they were two new ones so it wasn't down to wear. Possibly new old stock but they looked fine. If I could get a genuine Elmo belt for the projector, I might try it, but I don't suppose these are available now?

Posted by Mark Todd (Member # 96) on February 01, 2015, 05:42 PM:

New ones for me caused issues as well oddly.

Decent round ones are just the Job.

The ES Photgraphic round 2 belt set for the ST180 seems very good.£11.99.

Best Mark.

Posted by Tom Photiou (Member # 130) on February 02, 2015, 06:32 AM:

I must admit that I have only used genuine Elmo belts so perhaps the after market v ones aren't up to it, but as Mark says the round ones do the job just fine. [Wink]

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