8mm Forum: Repairing Elf ST/M Cam Tank issue - Sluggish? Lubrication? Or Worse? (with videos)

This is topic Repairing Elf ST/M Cam Tank issue - Sluggish? Lubrication? Or Worse? (with videos) in forum 16mm Forum at 8mm Forum.

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Posted by Can Sanalan (Member # 5988) on January 29, 2018, 08:20 AM:

Hello there,

I've recently acquired an Elf ST/M which had been kept in storage for 20+ years.
The previous owner said it belonged to a school and he saved it from the skip but hasn't used it since.
Anyway, as a side project I decided to take it and nurse it back to health.
I spent a few hours cleaning and dusting the machine. Changing the four belts, both arms, reverse and motor to cam tank. Cleaning off marks and stains. Need to buy some missing screws here and there.

The lamp, surprisingly, still works and the lens is in excellent condition without any scratches, dust or fungus.
The belts in the arms were disgusting. Looked like soft candy chews with spores on them. I've attached photos.

Now I'm no expert or professional when it comes servicing projectors so I didn't want to go in and take the whole thing apart down to the nuts and bolts cause I know from past experiences on other machines it can be a nightmare to put back.

Anyway my main issue with the project is the cam tank/shaft doesn't or sometimes sluggishly rotates.
In "rewind" it turns but sluggishly. In "forward" nothing.
The motor runs fine, in both directions.
I've taken videos and put them up on Youtube so you guys can see what I mean.
Here's the links:

Reverse:
https://www.youtube.com/watch?v=rpGO_IcYq8w

Forward:
https://www.youtube.com/watch?v=2Qw6UcjSB_M

Forward and reverse:
https://www.youtube.com/watch?v=bhTcWpWvmr4

As you can see the motor runs perfectly fine.
I've swapped the belts around just to make sure there's no slippage and they're both grease free.

Could the symptoms be old, sticky grease that's clogged up the gears/mechanism in the cam tank or is it something more worse?

I've also ordered some Super Lube which I'm waiting for.

I've seen Tom Photiou's NT1 clean up here which was helpful but I've hit a hurdle and I'd like to be able to repair this ST/M and get it up an running properly.

Any help much appreciated.
Thanks

Posted by Tom Photiou (Member # 130) on January 29, 2018, 11:26 AM:

More than likely everything grease wise has turned to sticky gluey stuff and needs to be all cleaned out and re done.

Posted by Phil Clarke (Member # 4299) on February 03, 2018, 01:53 PM:

I have a ST/M, they are excellent machines and well worth restoring IMO. The decomposed nitrile rubber belts are normal in a machine of this age; new belts are available online. You might also want to replace the cork clutch in the takeup spindle - it's a fairly easy job - 2.5mm cork gasket (available at auto spares shops) should give a good fit.

As for the cam tank assembly then you'll need the service manual which I can send you as a PDF if needed.

cheers ... phil

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