- Film jammed in gate, hole burned through frame. One or two feed rollers from platter out of position. This part is not so rare...however, consider that:

* The payout unit did not appear to be constricted in any way whatsoever. No film wrapped around, only one layer of film coming out, and feeding perfectly.

* The elevator had dropped (Speco LP-270) and there was about 80 feet of film piled up on the floor under the platter tree.

* The feature was about two minutes into reel 5 (of 7) when this occured.

* The next performance indicates no film damage whatsoever until a few minutes before the film actually jammed and stopped. The film remains perfect until suddenly, vertical green emulsion scratches appear a few moments prior to the end of reel 4.

* A patron who was watching the session that broke down commented about the green scratches just prior to the breakdown. These were not present beforehand to my knowledge, although they could have been (it was my first night there!)

* There is another feature in the complex which exhibits the same damage. Perfect, then halfway throught the feature, exactly the same scratch pattern. That print, according to management, had also been damaged whilst playing in that same auditorium.

That's about all I know. How is this possible? Of course, had I been lucky enough to have been there, the cause would have been apparent. As I was a little too late, I am totally stumped. Maybe I am just not thinking clearly and the answer is obvious to someone else. I am eliminating incorrect threading (I can't see how the film could have survived 4 spools without any trouble). Any theories or suggestions?

But that wouldn't explain 80 feet of film by the platter tree. To do that, the platter would have to feed out film faster than 90 feet per minute, until a jam at the projector shut things down. Maybe an occasional random platter malfunction?

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

Was your upper loop still OK? Was your reel 4/5 splice punched through OK?

Normally the microswitches on the Speco elevator will shut everything down if it drops, at our cinema this includes the zipper and dowser to prevent burn throughs.

Paul
 

Were the feed rollers way out of position or could they still be like that from a previous accident that was never fixed properly?

Paul
 

My first suspect would be as John P. pointed out: A splice somehow got stuck. Then it let go causing the film to "snap" like a rubber band.

I have had this happen when the splicer leaves "tabs" hanging over the edge of the film. You can do one of two things:

1) Inspect the entire print and use a knife or scissors to trim the edges.

2) Use a razor blade and "skin-off" any splices that stick up from the print as it sits on the plater. I don't think I need mention the pitfalls of doing this but be SURE you only cut the splicing tape and NOT cut into the film!

Finally, I have had a couple of occurances where some idiot who had the print before used masking tape to break down the film which left a patch of "Stick-Umm" on the film. If you are in a hurry to build up the film you don't always catch those kinds of things but it pays to double check, even if it takes you a few extra minutes.
 

Does the take up ride low on the platter tree? It probably does if it's a four tier LP-270. If it rides too low, the switch may have been activated which would cause the above scenario.

Get the kill switch working with the automation...

Let's get back to it:

Brad: Soundtrack down. The film was on the floor from the feed-out end now that I read what Daryl wrote, although I originally misattributed it as the take-up end. The elevator had dropped; or at least it was down by the time I arrived, with film piled up under it. To wit: if the take-up failed, wouldn't film pile up under the projector? That doesn't sit right with me either...

Paul C: The upper loop was pulled tight and the frame in the gate was burned through and feed rollers bent out of position: all the classic symptoms of a feed failure due to a wraparound or two layers of film being pulled through the payout unit. The strange thing is that no constricture was evident whatsoever and the feed unit was happy. The source of the lack of feed was not apparent. The reel 4/5 splice may be suspect; unfortunately there wasn't time for me to examine it personally. The film damage (aka green scratches) start well before the join from reel 4 to 5, however. It still could have been something sticky, however.

Paul C again(!): To address your second post. It wasn't a 'pile-up' (film collected in projector at upper feed sprocket). It was all single file, just pulled tight. The rollers were way out of position, yes.

Daryl: Correct: As you point out, the pile of film should be under the projector, not under the tree in the case of a take-up failure. The bottom payout roller is fixed (not on a rail and is located quite close to the floor. I have never experienced nor could I have previously imagined a 'static payout' but your theory answers all the variables and makes perfect sense. Could you tell me more about how it works...does the static accumulate between the bottom feed roller and the floor itself, thereby drawing film to it? This would of course cause the projector to 'fight' the feed for a while, dragging the film through everything until it finally gets snagged, and game over.

Daryl, John and others: Being my first night back at that theatre since it was automated I am not sure if there is a safety cutout on the elevator or feed rollers at all. I haven't had a chance to test it to see just what was done. I will have to check to see what's fitted. No payout failsafes as far as I can tell thus far.

Has anyone else experienced what Daryl describes? I probably would never have thought of this, but it all adds up now. Daryl, can you tell me more about this phenomenon. When you say that the lower the roller is the worse the problem, I take it you're referring to the charge that builds up to the floor - is this how it occurs? Sorry if this seems obvious but I'm just trying to see if I understand this correctly.

Thanks for all the responses and once again, I apologise for not responding sooner.

What I was referring to involves the payout roller. We use three deck systems that have been retrofitted with payout failsafes. A way to shut the projector down before it damagege the film and causes a burn thru. This roller is located about a foot from the floor. What can happen is the film can loop it's self at that roller if it jerks just right or you are pulling it quickly when threading. Static from the floor can pull the film downward and the speed of the payout platter can push the film thru the rollers faster than the projector is pulling the film thru. I have only had this happen a couple of times. If not caught the film will pile under the platters and the film will become dirty and scratched. Since the film is piling in the floor the weight from it could force the film to snag in a roller causing the projector to jam. I never had this problem until I installed the new payout failsafes. If possable can you take some quick pictures the next time this happens and have brad post them here. Hopefully it will not happen again.
 

Thanks very much for that - I think you've got it! The wonderful thing about Film-Tech - and the internet in general - is that someone, somewhere will have experiened the same kind of phenomenon, no matter how obscure.

Over-tension payout failsafes in that theatre are well overdue. I think that eliminating static from the film (using FilmGuard) would also go a long way towards preventing this again (if the film bears no static, it cannot be attracted to the floor other than through gravity).

I feel that over-tension devices should be standard equipment on platters. So much damage could have been avoided if this was the case. Kinoton platters seem to come equipped that way. They also have no 'down' rollers on payout either, which helps: after the payout unit, the film exits upwards as normal, then continues going up and across to the projector without going all the way down then back up again. That design principle alone would make 'static payout' inherently impossible on a Kinoton!
 

------------------
John Eickhof President, Chief Slave
Northwest Theatre Equipment Co., Inc.
P.O.Box 258
Wendell, ID. 83355-0258
208-536-5489
email: jeickhof@nteequip.com
 

------------------
John Eickhof President, Chief Slave
Northwest Theatre Equipment Co., Inc.
P.O.Box 258
Wendell, ID. 83355-0258
208-536-5489
email: jeickhof@nteequip.com