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Author Topic: Vertical film scratches on Simplex 1050 (resolved?) John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 03-05-2010 06:36 PM                     Hey, Jon! Post some pictures and we'll see if we can help! --jhawk  |  IP: Logged Justin Hamaker Film God Posts: 2253 From: Lakeport, CA USA Registered: Jan 2004 posted 03-05-2010 06:38 PM                        What I found was a roller on the brain which was not spinning freely. We had one particular roller where the round shaft the roller mounts to had come loose from the hex nut base. This was on an AW3 platter that was new in 1997. I'm still not comfortable I know exactly what was causing the scratches, but the moment we stopped using that brain the scratches stopped.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 03-05-2010 07:59 PM                     Note, a common cause of base scratches on a Simplex (except the Millennium) is an upside down intermittent shoe. The hardware that is being used will often rattle the screw loose and people put the shoe on any old way (experience has shown that they get it wrong 95% of the time). If one looks at the shoe carefully, they will see that the radius of the shoe is much shorter (smaller) on the exiting portion of the shoe than the entrance. This shorter radius pulls the film away from the tang that holds the shoe. If the shoe is put on upside down, and depending on the tang, and the depth the gate closes, the end of the tang WILL rub the film. I highly recommend having a stick of blue-loctite (looks kinda like chapstick) Amazon picture of Blue Loctite ...it will keep the screw from rattling off but does not prevent one from removing the screw. I like the stick form of loctite because it doesn't dry out in one's tool case nor get all messy. Do NOT use RED however!  |  IP: Logged Jon Petersen Film Handler Posts: 6 From: Des Moines, IA Registered: Nov 2008 posted 03-06-2010 12:48 PM                        I think I can rule out the brain being the source. I've swapped the brain with others from other booths. That's not it. One theory that has been floated my way was that it only takes one or two 'mis-threadings' to initially cause the base sratches. Then as the print is run more and more, the scratches fill with dirt and oil, making them appear on-screen to be getting worse. (I guess that is where Film Gaurd comes in. I just hope the higher-ups will agree to make the investment.) This mis-thread theory seems to make sense being that this is the only Simplex I have (The three others are Vic 8s), and this is the only auditorium where the scratches are occuring. I will try to get some pics up. Thanks for your input.  |  IP: Logged John Wilson Film God Posts: 5438 From: Sydney, Australia. Registered: Dec 1999 posted 03-07-2010 02:02 PM                     Jon If you really want us to help with your scratching issues, you need to post a picture of the damage...without it we're just flying blind.  |  IP: Logged Jon Petersen Film Handler Posts: 6 From: Des Moines, IA Registered: Nov 2008 posted 03-08-2010 03:04 PM                        PROBLEM SOLVED! Fortunately, I figured it out. Unfortunately, I can place the blame squarely on my own shoulders (more or less). I was lazy, then I was blind, then I was stubborn. It turns out that one of my floor managers, who is no longer a regular projectionist, but will occationally (average less than two times per week) thread a film when we are short-handed, has been consistantly mis-threading that projector for weeks. An incorrect film path through the film detector allows the projector to run perfectly, while scratching the cuss out of the print. Since taking over as a floor manager, she had a hiatus from threading any film. Recently, she has been called upon to thread a couple of times. I should have re-evaluated her more thoughouly before she resumed some of the projection duties. (That was me being lazy.) Of course, when the scratches first occured, the first thing I thought of was that someone must be mis-threading. I even suspected the very same incorrect film path as a way that the film could be scratched, but thought,"No. That can't be. No one would actually thread it that way." (That was me being blind.) Finally, after being told over and over that the problem does "not lie with the machine" and rather "with one of your projectionists" by my local cinema service guys, I refused to listen. "No. That can't be. They wouldn't do that. My people are reliable. It has to be the machine." (That was me being stubborn) I was actually in the process of having each of my projectionists thread the machine while I watched, just to eliminated the possibility of the claim being made. The first two guys checked out fine. Just before I was about to test the threading capabilities of my floor manager, twenty wrong things happened at the same time (as they often do). In all of the chaos, she ran upstairs, threaded the film and started it while I was taking care of nineteen of the twenty wrong things. Thirty minutes later, I ran upstairs and was horrified! There it was! The misthread! In the same place that I suspected then discounted. I stppped the film (Alice in Wonderland - 110 people in the auditorium), corrected the path, and started it up again. Long story, I know. Thanks for reading. Thanks for your help. Hopefully I won't need it anymore.  |  IP: Logged Justin Hamaker Film God Posts: 2253 From: Lakeport, CA USA Registered: Jan 2004 posted 03-29-2010 09:40 PM                        As I said before, I was never able to figure out exactly what was causing our scratches before. In the last week we've started getting identical scratches on the same platter. Right now they are fairly faint and I'm running with film guard every show to help make them better. I am nearly positive this is a platter problem, but I don't know what is causing such steady and perfectly vertical scratches. What I did to make the problem go away is time the platter, disassemble and clean the brain, changed the platter bearings on one deck, and there might have been one other thing. I haven't been having any problems with this platter in general, but occasionally it won't take up right away on the first show of the day, causing the projector to shut down immediately after it starts. Last night I did find the middle deck was lagging a bit on payout so I turned up the HI pot a small amount. This is a simplex 1050 with a Christie AW3 that was new in 1997.  |  IP: Logged Joe Redifer You need a beating today Posts: 12859 From: Denver, Colorado Registered: May 99 posted 03-30-2010 12:17 AM                        Justin, I have seen scratches like that before on one of those ancient Simplex soundheads (not the 5-star, the one that has two sprockets in it). Is that what you use? If so, you'll likely see the base side of the film lightly rubbing against the pad roller on one of the sprockets at the loop. Solution: make smaller loops.  |  IP: Logged Justin Hamaker Film God Posts: 2253 From: Lakeport, CA USA Registered: Jan 2004 posted 03-30-2010 01:24 AM                        Joe, I'm nearly 100% certain these scratches are related to the platter. I remembered that when this was happening last summer we stopped using the middle deck and stopped getting scratched film. I just wish I could peg down what is actually happening.  |  IP: Logged Joe Redifer You need a beating today Posts: 12859 From: Denver, Colorado Registered: May 99 posted 03-30-2010 11:06 AM                        If the scratches are rock-steady then I find it unlikely to be the platter.  |  IP: Logged Mike Blakesley Film God Posts: 12767 From: Forsyth, Montana Registered: Jun 99 posted 03-30-2010 12:07 PM                        If the scratches are being caused by a stopped roller then it could be the platter, but if they were caused by the film rubbing across a post or a guide, then I'd think the scratches would move around from side to side a little.  |  IP: Logged Jeremy Weigel Phenomenal Film Handler Posts: 1062 From: Edmond, OK, USA Registered: Mar 2007 posted 03-30-2010 12:48 PM                     Have you laced the film up and stopped the machine when the scratches appear? Carefully inspect every contact point where those scratches are located (looks like you have at least 4 starting just left of center and over towards the right)paying special attention to those surfaces that contact the base side of the film since the scratches are black. Also, can you post pics of your entire setup of this machine?  |  IP: Logged Matt Skilton Film Handler Posts: 43 From: Bromley, Kent, UK Registered: May 2009 posted 04-12-2010 05:15 AM                        Hi guys, we're having a mysterious base scratching issue at the moment. The scratches tend to be very faint and very wavy, ranging from Left-Hand side, Centre and Right-Hand side in the same prints (although the majority are Centre and RHS). We can't even pin it down to just one projector or platter because it's happened to many prints, some of which haven't shared the same screen. They are also intermittent; some reels are fine while others have a more continuous scratch. We also use AW3 platters and Vic-5 projectors. We've inspected the rollers and film paths and can find nothing wrong. It's very frustrating as we'd really like to find out what's doing it. This week we've changed all the feeder unit guide bars and tips so that they are now all smooth but we are clutching at straws with this one it has to be said.  |  IP: Logged Jim Cassedy Phenomenal Film Handler Posts: 1661 From: San Francisco, CA Registered: Dec 2006 posted 04-12-2010 10:04 AM                     The last two times I've seen scratches such as you describe, it's been caused by a dragging (optical) sound head drum, or a misthreading in the soundhead area. But check the sound drum carefully. Last year I had one sound head drum that passed the "spin test" but I later discovered that when I spun it with my finger it looked and felt 'OK', but after about a minute of film running through it, it began to slow down due to a faulty bearing. It still looked like it was turning normally, but it was dragging just enough to cause long, steady vertical black lines through the entire print. I finially discovered and confirmed the problem using an optical tachometer, and comparing the speed of the 'bad' sound head flywheel against the speed of the flywheel in another projector. I think the bearing cost me well under $50 to replace. Unfortunately, the print cost about $1800 to replace.  |  IP: Logged Matt Skilton Film Handler Posts: 43 From: Bromley, Kent, UK Registered: May 2009 posted 04-13-2010 04:40 AM                        Cheers Jim. My colleague (Tom, who is also on these forums) also suspected the sound drum as, apart from the feeder until, it's the only part that can potentially rub against the whole print. I shall try and investigate as best as I can. I'm suspecting one or two screens that could be the culprit.  |  IP: Logged

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