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Author Topic: Bizzare Random Upper Reel Problem Martin McCaffery Film God Posts: 2481 From: Montgomery, AL Registered: Jun 99 posted 01-13-2009 09:31 PM                        This is a problem that has occurred maybe 6 times in the last 2 years. During the last minute or so of the reel, we lose the upper loop, and if we don't get to the machine in time, the film is pulled all the way through, from the top down. The only other consistent factor is it only happens when using the film cleaner. And only on one machine. Simplex 35 6k reel, floating hub. Every time but tonight, only happened with 4 reels loaded on reel. No indication of hub freezing. Clutch pads have been replaced. dry felt. No indication of clutch freezing No indication of Cleaner freezing. No indication of upper sprocket freezing or slipping. A little play, but not more than in the lower, post intermittent sprocket. I'm stumped. Anyone seen this before?  |  IP: Logged John Walsh Film God Posts: 2490 From: Connecticut, USA, Earth, Milky Way Registered: Oct 1999 posted 01-13-2009 09:35 PM                     Could the upper pad roller arm not being locked down; ie the spring is weak?  |  IP: Logged Martin McCaffery Film God Posts: 2481 From: Montgomery, AL Registered: Jun 99 posted 01-13-2009 09:39 PM                        Just checked, not the pad roller. I should add that the film is being pulled tight, like the upper reel has frozen. Every time it has happened that I've been able to check, both the reel and the clutch rotate fine.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 01-14-2009 11:42 AM                     Back off your upper arm clutch tension. It takes very little to do the job right. The film does not need to be kept snug on the rollers entering the projector during normal operation. (This might not be your situation, but most people set them too tight.)  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 01-14-2009 01:38 PM                        What size hubs do the feed reels have?  |  IP: Logged Kenneth Wuepper Phenomenal Film Handler Posts: 1026 From: Saginaw, MI, USA Registered: Feb 2002 posted 01-14-2009 02:21 PM                     I would try to check the bearings on the shaft of the payout magazine/arm. Worn bearings tend to 'freeze up' and cause major drag on the shaft. Those bearings carry a very heavy load when the reel is full. The worn raceway or worn ball bearings can cause the bearing to become locked momentarily causing just the effect you describe. I have often thought that this would be a great application for needle or roller bearings as they carry a heavier load than the ball bearings. Lubrication is not an option once the wear is at this point. KEN  |  IP: Logged Rick Raskin Phenomenal Film Handler Posts: 1100 From: Manassas Virginia Registered: Jan 2003 posted 01-14-2009 02:35 PM                     Sounds like a tension problem to me, either from worn bearings or the tension adjustment itself. With a full reel there is sufficient energy in the motion of the reel to overcome the drag on the shaft, but as the film unloads the energy exhibited by the reel's motion decreases and reaches a point where it is insufficient to overcome the drag. Sound feasible?  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 01-14-2009 03:44 PM                     Screw the reel arms! Install anuomation and a platter system instead . Mark  |  IP: Logged Sean Weitzel Jedi Master Film Handler Posts: 619 From: Vacaville, CA (1790 miles west of Rockwall) Registered: Dec 1999 posted 01-14-2009 04:27 PM                     Bite your tongue! Everyone knows platters scratch film!  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 01-14-2009 04:59 PM                     You silly people do not need Mr. Guttag and I to start another discussion.  |  IP: Logged Martin McCaffery Film God Posts: 2481 From: Montgomery, AL Registered: Jun 99 posted 01-14-2009 09:02 PM                        No problems with it tonight, but then the film cleaner was on the other machine, and I did say it was random. Loosened the tension on the upper clutch and checked the bearings on the upper spindle. They appear and feel fine. 5 inch hub, 26 inch reels. Getting a platter is fairly low on my list of things to do;>  |  IP: Logged Martin McCaffery Film God Posts: 2481 From: Montgomery, AL Registered: Jun 99 posted 09-01-2009 09:03 PM                        Problem started up again in the last couple of days. It starts with the upper loop losing about one sprocket at a time slowly until there is a total fail, which, if the projectionist doesn't get to it in time, rips up the film. Still happens apparently randomly, but happened Sunday night and tonight. No problem last night. The projectionist stopped it just when it started tonight (stopping the show). Re-threaded and started the machine. Immediately happened again. We tried one more time and it ran a couple of minutes and started slowly happening while I was watching it. The bottom loop is not getting bigger, and the fail pulls out the bottom loop, too. This only takes place in the last few minutes of the reel, so by then we were close enough for a change over. Checked everything listed above. Haven't had the problem since January. All gears and sprockets seem to be fine. Could the clutch be somehow tightening itself? Totally stumped.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 09-01-2009 11:40 PM                     The clutch, depending on style, may need lubrication...you should SERIOUSLY stop using 5x26s...7x25s will not have problems...you'd be amazed at the difference...particularly if you use floating hubs.  |  IP: Logged John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 09-02-2009 01:11 AM                     It's a good idea to test with more load than you should ever see, just to you're sure you're good in unfortseen circumstances. In addition to dragging on the reel by hand (with a rag, or whatever), mount a split reel and run film off a 3" core, a 2" core, or even a 1" trailer sleeve. If you can do handle a 2" core, then you're good for any manner of 5" hub. If you can't, well, lubricate, adjust, etc., until you can. --jhawk  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 09-02-2009 01:53 AM                     true .. 5x26 contains a lot of rotational torque when the reel is turning that fast even with slip hub reels with only 5 minutes of film remaining.... Good suggestion in reducing the upper shaft tension to almost nil, or at least a couple of ounces of string tension. -Monte  |  IP: Logged

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