8mm Forum: Film clatter.

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Posted by Nick Field (Member # 2132) on June 21, 2011, 03:42 PM:

Hi all just wondering if any of you ever had intermittent clatter from certain prints? I seem to get it on one particular film as the clatter happens the picture becomes unsteady like as if it's passing a splice. I was kinda wondering if it's the claw catching now and again against the film sprockets, could a good film lube cure the problem? The film is in quite good condition no warping,splices curling etc. [Confused]

Posted by Lee Mannering (Member # 728) on June 21, 2011, 04:51 PM:

Hi Nick. You will probably find this is due from older Acetate prints which have shrunken thus causing the sprocket holes to be closer together. The projectors claw struggles to register and causes the clatter. Try some good quality film cleaner or lube as they call it in the US. Older prints need much loving when projecting..

Posted by Nick Field (Member # 2132) on June 22, 2011, 12:10 AM:

Hi this is on an LPP polyester stock dated around 1983.

Posted by Lee Mannering (Member # 728) on June 22, 2011, 03:54 AM:

Poly should be OK nick. Does it make the noise in the exact same place of the film each time?

Posted by Nick Field (Member # 2132) on June 22, 2011, 02:09 PM:

It's quite hard to tell really, the clatter seems to be quite random no specific places, it seems to be on all three reels of the feature so ruling out a problem reel.

Posted by Allan Broadfield (Member # 2298) on June 29, 2011, 04:50 PM:

I'm not forwarding this as a suggestion, just as a point of interest (I hope). When I worked as a cinema projectionist in the late fifties, early sixties, we would have a similar effect of 'clatter' and unsteadiness with brand new b/w copies. The noise was awful, and in those days we were issued with packets of sticks of hard wax, which would be held against the sprocket teeth immediately above the picture gate and would calm the whole thing down. Don't know if this is still done. The gate would need extra cleaning after each reel. When new prints arrived, they would often have floor polish rubbed into them before spooling up, to make the film run more smoothly. It did the job, but I wouldn't recommend it for your problem! I should imagine the prints in question are probably either slightly shrunken as suggested, and/or brittle. In the film labs we would sometimes have to treat shrunken negatives in a redimensioning cabinet that would sauna the film back to normal ready for printing, but the print would need to be made pretty quick before the film reverted back.

Posted by Nick Field (Member # 2132) on July 01, 2011, 12:03 AM:

I may try a bit of film cleaner/lube to see if it runs better and may be put another print over top to compare sprocket hole distance etc.

Posted by Joe McAllister (Member # 825) on July 01, 2011, 03:12 AM:

Hi I think there are two possibillities, the first as many have suggested is the print needs some lubrication,this would be likely if the print has been cleaned too aggressively. New prints were waxed in the lab and some film cleaners will remove this coating. I have a little machine for re waxing prints that have lost their coating.
The other possibility is that the gate on your projector does not exert enough pressure.
Not necessarily a fault as such but polyester prints are thinner than acetate so some adjustment may be required. Running the print on another projector may be a solution or replacing the gate pressure springs.

Posted by Nick Field (Member # 2132) on July 01, 2011, 03:19 PM:

I do have other poly prints that don't have the problem and keep a rock steady picture,just seems to be this one feature for some reason.I'm going to Derann on sunday so I may pick up some film lube and see if that helps.

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