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» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Scratching on a simplex head... where's it coming from? (Page 1)

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Author Topic: Scratching on a simplex head... where's it coming from? Tyler Potts Expert Film Handler Posts: 159 From: Anderson, SC, USA Registered: Sep 2008 posted 11-17-2008 07:51 PM                       Ok, I'm at my wits end here. We've scratch a print just about every week for a month on this one projector. I've cleaned it out, looked for problem areas, replaced tension bands, lubed all rollers, and still it scratches. I'll build a print, I'll run it for two days, then I'll be off or on the floor for 2 days, then when I come back, the print is scratched. Usually a yellow/green emulsion vertical line about a foot from the left of the screen. Pretty strong, doesn't waver. A few prints this is coupled with one on the right, or once even straight down the middle. I've asked our tech and he thinks it might be the aperture plate, but I don't see any burs on it and it's clean. I'm guessing the scratch is happening somewhere below the gate because people are noticing it after a shift (either casting blame to the joe before, or its scratching after the image is on screen). What's worse is there's no dirt or shedding in the machine after a show to help locate where it would be scratching. I thought maybe the metal guide on the wrap detector on top of the tree, or maybe the guide on top of the sound drum, but those look clean. Here's the equipment I'm running and a few pictures to help: Strong platters Simplex Millennium PR2000 head Simplex 5 star soundhead FM-35 automation sensor Brain with print of Role Models Brain on top platter Full Strong platters shot Millennium head 5 Star soundhead and FM-35 automation sensor Closeup of closed sound drum & guide roller Closeup of FM-35 unit Takeup rollers If anyone has any experience with this platter system or projector or soundhead, I'm all ears as to what is causing these scratches. We can't get any more replacement prints for another year because of this.  |  IP: Logged Joe Redifer You need a beating today Posts: 12859 From: Denver, Colorado Registered: May 99 posted 11-17-2008 08:13 PM                        If you are getting the scratch on both flat and scope films, then that likely rules out the aperture plate. Maybe somebody there is threading under the locking pin of the take-up variac? I tried this when I was attempting to find out how someone scratched a print where I work.  |  IP: Logged John Wilson Film God Posts: 5438 From: Sydney, Australia. Registered: Dec 1999 posted 11-17-2008 08:14 PM                     Can you get a shot of the damaged print(s)?  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 11-17-2008 08:19 PM                     I got an 8plex of this exact same booth setup and we havent experienced any form of scratching with our STRONG setup. Is someone lame on how to frame and when you twist the FRAME bar, the lower loop bangs into the lower loop panel assembly?  |  IP: Logged Tyler Potts Expert Film Handler Posts: 159 From: Anderson, SC, USA Registered: Sep 2008 posted 11-17-2008 08:20 PM                       Joe, I'll try that tonight on some test film. John, I'll try to get a shot on this next show.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 11-17-2008 08:32 PM                     edit: wonder if the film is hitting that small box in front of the upper roller on the FM-35 unit? Have you got some takeup issues with the platters to maybe have some slack problems right there to allow the film to leave that upper roller and rub against that block? OR, the film is making contact with the back edge of the soundhead casing itself? Look on how the film would travel straight down to the FM-35 from the holdback sprocket, and there could be a risk of film contact with that edge on the casing.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 11-17-2008 08:41 PM                     Okay that doesn't jibe....you have yellow/green emulsion scratches...THERE HAS TO BE EMULSION SOMEWHERE! It can't just evaporate. Follow the emulsion side of the film the entire length of the threading...somewhere it is hitting and somehwere is some magenta colored dust...you don't get green, let alone yellow, without the magenta layer being scraped off. Steve  |  IP: Logged Tyler Potts Expert Film Handler Posts: 159 From: Anderson, SC, USA Registered: Sep 2008 posted 11-17-2008 10:37 PM                       Steve, the problem is I'm getting to this projector a show or two after the incident. And I swear its the case of the magical mystery emulsion. No signs. Monte, I tried and couldn't get the film to touch any part of the FM-35 unit that wasn't a roller. I'll try after this show with more test film to see if forgetting a roller might cause it to rub against anything. Joe, I had time to run some trailers where they looped under the variac's lock pin, no scratches, at least after 1 run through. I'm going to try running with the brain wrap detector totally tightened down, then at full tension against the gate to see if it is the aperture plate (then test with scope to see if it still scratches).  |  IP: Logged Joe Redifer You need a beating today Posts: 12859 From: Denver, Colorado Registered: May 99 posted 11-18-2008 12:08 AM                        None of the plastic rollers anywhere have a flat spot? I'd just take a trailer, load it up onto a ring and run it again and again and again until you see the scratches appear. Once they do appear, look for the emulsion that Steve describes. If they never appear, then it is likely that some other person is misthreading.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 11-18-2008 12:43 AM                     quote: Tyler Potts I'll try after this show with more test film to see if forgetting a roller might cause it to rub against anything. ..and I've seen film being missed going through the bottom roller heading to the platter on the machine and the film is dragging across the roller shafts/hdwe itself. Look for pink stuff down that area. I can't see aperture plate being the culprit since if the film was going through the trap even though, granted, the plate is close to the film plane. The scratches would have stop and go scratch markings instead of a continuous line due to a continous feed. Side question: Do you have DTS per chance? I've also seen film being ill-threaded through the reader also...by someone can miss that lower roller on the reader...look for pink stuff and wear on the edge of the reader frame as well.  |  IP: Logged Jonathan Worthing Master Film Handler Posts: 384 From: Hereford, UK Registered: Apr 2001 posted 11-18-2008 06:29 AM                     Do you see the scratch on the first showing on only on the second showing. If you are not sure run a clean trailer that has not been run until it has passed through from feed out to take up & stop the projector. Make marks on the film a places you can see the film edge, EG just as it comes off the feed out roller & just before it enters the projector & so on. Take the film out of the projector & look for the scratch. Where the scratch appears that is where the problem is.  |  IP: Logged Jim Cassedy Phenomenal Film Handler Posts: 1661 From: San Francisco, CA Registered: Dec 2006 posted 11-18-2008 09:45 AM                     quote: Monte L Fullmer Do you have DTS per chance? I've also seen film being ill-threaded through the reader Monte makes a good point. I've had two prints severely scratched this way when somoene missed the last roller on the DTS had, causing the film to drag across the top of the projector casting on it's way to the top feed sprocket. But in both cases the cause was obvious since it left a pile of film scrapings at the point of contact. It should have been obivous to the person running the print too, since this type of damage appears immediately on screen. Heck, I'll confess I even managed to do this myself once, but I immediately knew something was wrong and the only thing that got trashed was a trailer for "Speed Racer" which IMO was no great loss...  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 11-18-2008 10:20 AM                     I have had that happen when a threader went down through the FM35 wrong and scratched the emulsion on the angle metal that is the shroud for the presence/motion IR modules Also a incorrectly set padroller assembly especialy the one in the soundhead could put some interesting emulsion lines on  |  IP: Logged Chris Slycord Film God Posts: 2986 From: 퍼항시, 경상푹도, South Korea Registered: Mar 2007 posted 11-18-2008 10:28 AM                     What you should do is keep a log of when the scratches appear and compare that to who was working. Magical dust disappearing could simply be: 1) Guy scratches print 2) Guy goes to thread, see's pink dust 3) Guy cleans it off projector So if someone was inconsistent in threading (sometimes threads fine, others scratches) they could scratch it, clean up what would give it away to you then thread it up fine. Or they scratch and someone else takes over and cleans up the projector.  |  IP: Logged Joe Redifer You need a beating today Posts: 12859 From: Denver, Colorado Registered: May 99 posted 11-18-2008 10:45 AM                        How could one get an emulsion scratch on a DTS reader? I guess I just can't picture it ever getting misthreaded.  |  IP: Logged

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