8mm Forum: GS-1200 motor belt

This is topic GS-1200 motor belt in forum 8mm Forum at 8mm Forum.

To visit this topic, use this URL:
https://8mmforum.film-tech.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=009338

Posted by Vidar Olavesen (Member # 3354) on August 02, 2014, 11:36 AM:

Is this belt elastic at all or stiff as hell? I have troubles getting it fitted and was told to unsrew the motor to attach it. If I screw them on again, it runs slow. I have now a motor that's not exactly screwed in place, but it's working. Anyone can tell me if I got the wrong belt? If so, where to find the proper one?

The one that was on the machine was elastic and looked just like the ST-1200 belt, so I tried that. It lasted a couple of months

All help appreciated

Posted by Adrian Winchester (Member # 248) on August 02, 2014, 01:09 PM:

It's very stiff - I'm glad I haven't needed to change one.

Posted by Lars-Goran Ahlm (Member # 1908) on August 02, 2014, 03:48 PM:

I have recently changed the belt in my machine, and was afraid it would be a difficult operation, but it wasn't. Removing the old belt and placing the new took only one minute, whitout unscrewing anything. And it was a original, very stiff, Elmo belt, that was supplied as an extra when I bought the machine some years back.

Here is one place where you can buy belts:
http://shop.van-eck.net/BT-0492-M.html
Unfortunately you have bad timing as they just today started their summer vacation.

Posted by Paul Adsett (Member # 25) on August 02, 2014, 03:48 PM:

Never had understood that belt - what's the purpose of having teeth on the outside of the belt?

Posted by Vidar Olavesen (Member # 3354) on August 02, 2014, 04:32 PM:

I have three belt sets from Van Eck, so that's the same belt I have. There was no way in any hell at all I could get that on without loosening anything. Van Eck told me I had to also, just don't get why I can't screw it back on, if I do, it runs very slow.

Posted by Graham Ritchie (Member # 559) on August 02, 2014, 05:26 PM:

If you have the proper GS1200 belt, then you need to slacken the motor attachment screws to fit it. Also be sure you adjust the belt so you have "5mm of slack" ....that's very important, its just like adjusting your fan belt on a car.

You will certainly have problems if its adjusted way to tight.

Graham.

Posted by Vidar Olavesen (Member # 3354) on August 03, 2014, 02:44 AM:

There's no way of getting 5mm slack on these belts ... So, I assume I've done it wrong.

It's on, but the screws need to be very loose and now it at least runs at 24fps

Posted by Graham Ritchie (Member # 559) on August 03, 2014, 03:43 AM:

I can only think that you must have the wrong belt, as there is usually plenty of adjustment to get that 5mm side ways slack. I would recommend, not to run the motor as it is.

1...with loose screws
2...with a belt being that tight its not good for the motor and projector main shaft bearings.

Posted by Josef Grassmann (Member # 378) on August 04, 2014, 12:58 PM:

@ Paul
theeth on outside are cutouts to enable v-belt to keep good contact with small hubs. Belt can better follow small radius as it is not so stiff.

@ Vidar

V-belt is 3mm wide and outer circumference is approx. 281mm.
Mark belt on outside and roll it on table and measure length.

UBB.classic^TM 6.3.1.2