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Author Topic: Sound Warble Simplex XL Don Hallmark Film Handler Posts: 12 From: Andrews, TX. Registered: Nov 2005 posted 11-17-2005 10:31 PM                     I have a bad warble that is really noticeable in all music. This projector has set for several years but I just replaced all of the bearing in the sound head and on the drum. Could the motor cause that and not show up in the picture? I am a newbie again so I am stumped. [ 11-18-2005, 06:14 AM: Message edited by: Brad Miller ]  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 11-17-2005 11:07 PM                     Hopefully you utilized bearings on the sound drum that don't have any sort of seal on them. Any seal will put enopugh drag on the scanning drum so that it never quite reaches free wheeling film speed. Other than than the drum having some sort of drag on it from another place like the flywheel side there is little that would cause it. I assume you also overhauled the lateral guide roller as well and that it spins very freely..... Everything MUST spin like a top when you hand spin it and continue spinning. The sound drum should free spin for a minimum of 20 to 30 seconds after applied hand motion is removed. As for bearings on the sprocket shaft... I highly reccomend bearings with rubber seals for longer life. Keeps things outside out of the bearing out of it and whats inside it in place!! Could vaguely be belts that are excessively tight but if yours are the round tooth version that is highly unlikely. There should be about 1/4" to 3/8" slack on them.. at least. Mark  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 11-18-2005 12:17 AM                     I think you may have a flat spot on the lateral guide pinch roller and if it is a XL soundhead then it is possible that the inner and outer flywheel have been dinged and touching  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 11-18-2005 04:52 AM                     Go back to your post and remove your email address - this is a no-no here. Need to read the rules. Yep, flat spot on the lateral roller does this "bird warble" quite often. -Monte  |  IP: Logged Bill Enos Film God Posts: 2081 From: Richmond, Virginia, USA Registered: Apr 2000 posted 11-18-2005 07:34 AM                     Could be as simple as something stuck to the drum, some sticky tape residue will do it.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 11-18-2005 07:41 AM                     Monte, They should make you a moderator ! Also check that the rubber roller isn't split. Hard to see sometimes but this happens on older units... Mark  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 11-18-2005 09:08 AM                        Nothing to add except drum bearings are available that are covered, but that do not drag like rubber seals. They are somewhat hard to find. The cover stope about 0.001 from touching; keeps out dirt, but does not drag. louis  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 11-18-2005 09:08 AM                     There have also been instances where the viscous oil within the flywheel has leaked out (or been removed) and thus the drum never couples to the flywheel. Everythink spins but it isn't really coupled...see if the drum is spinning at the same speed as the flywheel.  |  IP: Logged Barry Hans Film Handler Posts: 92 From: Minneapolis, MN, USA Registered: May 2000 posted 11-18-2005 10:35 AM                        Also check the lateral guide roller upper bracket for a hairline crack that can cause the lgr to "bounce" just enough to cause a problem.  |  IP: Logged Don Hallmark Film Handler Posts: 12 From: Andrews, TX. Registered: Nov 2005 posted 11-18-2005 11:08 AM                     Thanks for all of the help. I replaced the rubber roller in the lateral guide assembly. All of the bearings are Simplex replacements. Thanks again,  |  IP: Logged Bob Koch Expert Film Handler Posts: 183 From: williams ca Registered: Nov 2001 posted 11-18-2005 12:56 PM                     Check the concealed spring between the upper and lower sections of the guide. The intended tension is probably missing. You have to seperate the two sections, pull out the coil spring and stretch it. Don`t lose the ball.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 11-18-2005 01:01 PM                        Barry: crack in upper bracket: we "stripped" 50 of these and found the crack in 39. Louis  |  IP: Logged Rick Raskin Phenomenal Film Handler Posts: 1100 From: Manassas Virginia Registered: Jan 2003 posted 11-18-2005 01:10 PM                     Not to sound condescending, but sometimes the most simple thing can be the cause. You are backing off only 2 perfs at the hold-back sprocket? More than that could cause a free loop around the sound drum.  |  IP: Logged Don Hallmark Film Handler Posts: 12 From: Andrews, TX. Registered: Nov 2005 posted 11-18-2005 03:16 PM                     Yes I am backing off 2 perfs at the hold back sprocket. When it is done at 1 perf you can hear the warble really bad. Just barely at 2 perfs. When I don't load the machine it gets to tight it seems. Thanks for the help.  |  IP: Logged Rick Raskin Phenomenal Film Handler Posts: 1100 From: Manassas Virginia Registered: Jan 2003 posted 11-18-2005 03:28 PM                     As mentioned earlier, it appears the sound drum may be binding and not spinning freely. That would be consistent when you run with a 1-perf back-off. It forces a tighter loop. Also, see Steve Guttag's post above.  |  IP: Logged

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