8mm Forum: Elmo St 1200 Takeup Arm Prob=SOLVED

This is topic Elmo St 1200 Takeup Arm Prob=SOLVED in forum 8mm equipment for sale/trade at 8mm Forum.

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Posted by Richard Bock (Member # 1926) on October 04, 2012, 10:03 AM:

I bought an almost pristine Elmo 1200 ST except for one thing. The take up arm is not turning. I opened the back and noticed that the white gears are turning but the spindle for the film reel on the arm is not moving. when I try and turn the spindle where the film takeup is it turns the gears with resistance. There is no free play. I also noticed on the rearmost gear pictured that the gear turns but not the spring mechanism. Is that normal? Any help appreciated, can post more pics or movie on request.

PS I put this in the wrong thread. Please refer to the proper thread-8mm Film Equipment for resolution. Sorry for double post.

[ October 06, 2012, 09:35 AM: Message edited by: Richard Bock ]

Posted by Paul Browning (Member # 2715) on October 04, 2012, 03:02 PM:

Hi Richard , have you tried the belt within the arm that the reel fits to on the outside, perhaps that belt has perished or come off ? just a thought .

Posted by Andrew Woodcock (Member # 3260) on October 04, 2012, 04:24 PM:

Hi Richard, I have two of these machines currently and have had several others in the past and have worked on them quite a bit over the years. They are a relatively easy machine to work on which to me, only adds to their appeal. It would appear that the spur gear or gears are not adjoined to the brass shaft that the mount on correctly. If you dismantle the assembly with the gears and spring on it, you will see that the inner part of the gear is specially shaped to fit onto the drive section of the shaft. Once this has been done assuming there is no damage to the shaped inner gear, then you will need to set the spring tension up by adjusting the collar sufficiently forward onto the spring so as to gain sufficient tension to be able to rewind a 1200ft full spool of film. In accordance with the service manual this should be done using a pull force guage from the centre of the take up spool mounting hub, however I have found that in reality on a well used machine you will need to excert a little more tension from the spring than the figures suggest so trial and error generally proves to be the only way of guaranteeing success on this. Once all this work is complete try it and if problems persist take the front coverplate off the reel arm and inspect the chain of gears and teeth within for damage, wear and lubrication levels. Hope this helps Andrew.

Posted by Richard Bock (Member # 1926) on October 04, 2012, 10:11 PM:

Thanks Andrew for the details you've outlined. It will save me much time and effort.

Posted by Roy Neil (Member # 913) on October 05, 2012, 05:03 AM:

I think the problem might be due to the way the gears are designed to disengage when the spindle is rotating in reverse - so when rewinding the takeup belt does not engage.

You may need to ensure the gear is free enough to slide back into the engaged position.

Posted by Richard Bock (Member # 1926) on October 07, 2012, 11:51 AM:

The gent who sold me the projector can also fix these and gave me these directions via email to fix the Elmo St1200 to like new operating condition. I thought I'd post the fix for this particular problem for the record:

"I see lubricant on the gear that may have gotten into this (clutch) assembly which may be resolved by loosening the allen key and removing the gear and metal collar for cleaning and adjustment. If this is the clutch assembly then there should be a compression washer or material between the teflon gear and the metal collar that should be cleaned and then recompressed (the stronger the compression, the stronger the takeup torque). Just not too tight.. the takeup reel/spindle needs to slip or it can break the film at a splice or a brittle area."

again sorry for double ;post

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