8mm Forum: ELMO ST-800 Questions

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Posted by Steve Klare (Member # 12) on December 29, 2003, 07:59 PM:

In the days since Christmas I've been making friends with the ELMO ST-800 I now have. I have a couple of minor issues:

1) I sense that there is a certain sequence of controls needed to get the auto-thread to work. Sometimes when I thread the film the guide over the sound head is closed and the film piles up instead of going in. Other times if I operate the selector switch and the thread control differently the guide is up and the film goes right in. I don't have the manual. Can anybody tell me the right way to thread this projector?

2) When I rewind I reach a certain point where the clutch on the front spindle slips. I think there is excessive drag on the rear spindle, any ideas?

It's a beautiful machine!

Posted by Jim Schrader (Member # 9) on December 30, 2003, 08:11 AM:

hi have you trimmed the ends of the film sometimes the film will do as you say pile up if it not trimmed with the trimmer on the machine, jim

Posted by Steve Klare (Member # 12) on December 30, 2003, 08:56 AM:

Yes, I used the machine's trimmer. It seems though that there is a specific sequence of turning the machine on and pushing down the threading control to get all the film guides to move into the right positions to thread. I'll figure it eventually, but hoped someone here knew for certain.

(Curses on those who sell used stuff without the manuals!!)

Also, any ideas where I can get an 800 foot take up reel designed for auto-threading?

Posted by Chris Quinn (Member # 129) on December 30, 2003, 12:55 PM:

Hi Steve,
I don't own a ST-800 i do have two ST-1200s and would thought they would work in the same way, The manual say's depress auto green lever until it locks, addvance the motor switch clock wise to the forward position, (this would be as projecting a film) insert film leader into the auto thread slot. Auto thread releases automatically when film reaches take up reel, or there is a button to depress near were the films comes out to be taken up by the take up reel. Hope this helps until some one with more knowledge come on. Chris.

Posted by Steve Klare (Member # 12) on December 30, 2003, 01:04 PM:

Hmmmm.....

This sounds worth trying!

Thanks!

Posted by Barry Johnson (Member # 84) on December 31, 2003, 04:12 AM:

Concur with Chris and his comments.Further to this though,if you actually switch the projector to 'show' it will disengage the mechanism-at least it did on the 800 I used to own,with my 1200 though,this is not the case.

Posted by Chris Quinn (Member # 129) on December 31, 2003, 04:47 AM:

Hi Steve,
Well, I suppose that the 1200 may have a different mechanism due to its separate switch for the lamp. Still I would say that if this does not work then try depressing the green auto button before setting the projector to its first position and not to the show position, if it is still causing problems there may be a problem mechanically.
Sounds strange, [Confused]

Happy New Year. Chris.

Posted by Steve Klare (Member # 12) on December 31, 2003, 06:51 AM:

I think I have the autothread figured out. When I set the switch to forward without the lamp the guides retract for threading. When I flip it again to forward with the lamp on they close. (Basically what Barry is saying.)

OK, one last thing. The rear spindle isn't turning freely during rewind. So much that it makes the front spindle slip on it's clutch. Any thoughts?

Posted by Kevin Faulkner (Member # 6) on December 31, 2003, 07:37 AM:

Hi Steve,
The slipping clutch could be down to a number of things. The rear take-up clutch could be out of adjustment or the slight grease that Elmo apply to the cork clutch pads could have dried out. The clutch for the rewind arm could also be in need of adjustment or someone has applied a lot of grease onto the cork pad. I would have a close look at these clutches to see if they look as if they have been tampered with.
If the rear take-up is working ok when running film then I would bet on it being the rewind clutch out of adjustment or even a worn cork pad. These cork pads do wear with age which means readjusting the clutch tension to compensate. Hope that helps, Kevin.

Posted by Steve Klare (Member # 12) on January 10, 2004, 03:33 PM:

Hi Kevin,

It seems to me that the front spindle is giving me plenty of tension. It is the rear being stiff during rewind that is the problem. The front spindle free-wheels much easier than the rear and if I disengage the film from the rear spindle during rewind it moves plenty fast.

The dealer I bought the projector from replaced all the belts. I wonder if the belt going over from the selector gear to the rear spindle drive is too tight, since during rewind the rear clutch is slipping.

Is this supposed to happen? I would imagine the spindle,it's gears and this belt are all supposed to move while rewinding.

BTW The rear cork did look a little dry, what is the proper lubricant?

Thanks!

Posted by Kevin Faulkner (Member # 6) on January 12, 2004, 06:05 PM:

Steve, Its difficcult to diagnose without seeing the machine. It is possible that the belts are too tight bot not so likely. I think the grease on the cork for the takeup arm clutch is probably dry or out of adjustment. I use "Castrol Heavy Grease" and only apply a very slight film to the cork surfaces, just enough to take the dryness away and then assemble and readjust to get the tension correct on takeup with a full 1200ft spool. Once this is done rewind should be ok. I know this is a silly question to ask but you are pushing the yellow lever down for rewinding. I know a guy who didnt and was complaining he couldnt rewind am 800ft spool let alone a 1200ft spool. Just a thought as you may not have an instruction manual and would possibly then not know about this lever.

Kev.

Posted by Steve Klare (Member # 12) on January 12, 2004, 10:42 PM:

Hi Kevin,

My machine doesn't have a yellow lever anywhere.

(remember, we're talking ST-800 not a GS-1200)

What would this lever do?

Thanks!

Posted by Kevin Faulkner (Member # 6) on January 13, 2004, 04:51 AM:

Your spot on Steve, I was thinking ST1200. Silly me it must be my age! [Wink]

I think it has to be down to that cork clutch which is too dry and not slipping as it should be. Try undoing the grub screw that is in the collar pushing against the spring on the clutch and then release the tension a little. If that works, strip down the whole assay and clean the cork and re assemble with a knats of grease on the cork surface. That should cure it. [Smile]

Kev.

Posted by Jason Clark (Member # 1064) on April 01, 2008, 08:21 AM:

Sorry to bring back such an old topic but I seem to be having the same problem and had a question. In the last reply you say to strip down the whole thing and clean the cork but im not sure how to get the cork out to clean it. Do you just loosen the grub screw all the way to get it to come apart?
Thanks for any help,
Jason

Posted by Steve Klare (Member # 12) on April 01, 2008, 09:38 AM:

Ah!, Memories!,

The solution to this one turned out to be really easy. It seems that the ST-800 is set up to use the ELMO 800 foot reel for take-up. The difference is this reel has a center core diameter of about 4 inches: pretty big compared to most other reels.

During rewind this means that a given linear film speed the rear spindle will be forced to rotate much faster with other reel sizes and its drag will be increased.

-bigger core=more leverage=less drag.

On large reels of film this means that as the film piles up on the supply reel, the torque required to drag that rear spindle goes up until the front spindle clutch slips, and the rewind grinds to a halt.

It's really not so much a factor of the rear clutch, since the drive for the rear spindle is disengaged during rewind and is supposed to freewheel, so all that the clutch is driving at that point is two gears and a belt between their pulleys. I don't think the rear clutch should be slipping at this point.

The Gepe 800 foot reel is basically identical to the ELMO one. Once I got one the problem went away.

The machine that started this thread is still in use and has been very little trouble. It will rewind full 800 foot reels with no complaints.

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