This is topic Platter Keeps Tossing Prints in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Jacob Szewczyk (Member # 2513) on 07-16-2004, 05:38 PM:
Hi, once again, I have a problem with the piece of
platters at my thearter. We're using CFS Super Platters, and on one particular platter, the last reel of about every movie on it eaither gets tossed of comes very close to falling off the platter. Whats causing this?
Posted by Will Kutler (Member # 770) on 07-16-2004, 05:48 PM:
I have no personal experience with the CFS platters, but from what I hear they are not too well liked.
What you are experiencing is a STATIC ELECTRICITY problem! Solutions for this problem have been beaten to death in other threads...but here's a recap:
Ensure your platter is properly grounded in the electrical outlet.
The use of aluminum rollers such as what Christie has done with their pay-out heads.
Using FILM-GUARD!
Some have also lightly sprayed the top of the print with A LIGHT COAT of ant-static clothing spray.
Using the platter rings that Brad now has.
Also ensuring the platter is properly timed and operating smoothly!
Posted by Jack Ondracek (Member # 1466) on 07-16-2004, 06:20 PM:
A CFS platter can get out-of-time just as easily as a Strong.
IF you haven't moved the platter motors since this problem came up, check the motor that is running takeup when you're in "toss-the-print" mode. If the drive pulley is binding up, it will slow the motor down, forcing the variac to provide more voltage to compensate. That will also cause your feed platter to build up more speed before the feed switch turns it off... and you know the rest.
On the other hand, IF you've changed motor positions recently, either put it back or check your manual for timing instructions.
Posted by Brad Miller (Member # 2) on 07-16-2004, 06:20 PM:
Will is sort-of on the right track.
*CFS platters are pure evil straight from the bowels of hell.
*The aluminum rollers don't do anything. Save your money.
*Do not use FG and then go spraying some kind of anti-static spray designed for clothes. FG will work just fine on it's own, but if you use something else, don't go playing chemist and mix tons of items together. You could end up glueing the print together with some untested concoction.
*The safety rings will not work on CFS platters.
*Throw those platters in the trash or burn the building down, whichever is easiest.
*If disposing or burning the building down is out of the question, ask Aaron Sisemore for assistance, as he has to deal with a slew of those at his theaters.
*I feel your pain and you have my deepest sympathies for having to deal with them.
Posted by John Pytlak (Member # 331) on 07-16-2004, 07:17 PM:
Kodak VISION Color Print Film has a conductive antistatic backing that makes it much more resistant to "static cling" than previous color print films. The higher humidities of summer help control static too, as most static problems occur in the winter, when indoor heating dries out the film emulsion, making it less conductive. In the US, "static cling" problems tended to occur most from November through April.
I suspect most of the issue you describe is incorrect platter timing, since it occurs mostly on a particular platter. It is also very important to restrain the outside circumference of the film roll, so abrupt variations in speed can't throw the last reel or two off center, and eventually off the platter.
Posted by Mark Gulbrandsen (Member # 72) on 07-16-2004, 07:46 PM:
In Utah they are known as "Stupid Platters". Of course we also have the Neumade "Neurotic" platters as well. They are both on the same level of quality. You will find that those that actually like these two platters are those that are still driving and liking their Yugos!
Mark
Posted by Aaron Sisemore (Member # 145) on 07-16-2004, 07:56 PM:
Several things may be happening here:
1. IS the motor 'vibrating' when it runs up as the switch kicks in? The vibration can cause the end of a print (which weighs very little) to literally vibrate right off the platter deck!
Solution: Replace the motor. If the new motor vibrates excessively at speed, try bending the bracket the motor mounts to until the vibration is minimized.
2. Does the 'dancer' roller on the back of the platter tree oscillate up and down more than an inch or so as the film gets near the end? Possible causes here are:
a. The take up disc is bent or warped causing erratic dancer movement- Solution: Straighten or replace the disc.
b. The motor is bad and has an intermittent open circuit- Solution: replace the motor.
Static electricity doesn't cause thrown prints on CFS platters, it only causes brainwraps.
Hope this helps.
-Aaron
Posted by Mark Gulbrandsen (Member # 72) on 07-16-2004, 08:33 PM:
Aaron,
I heard that all you guys at Cinema West drive Yugos....
. Don't you have somrthing good in the warehouse you could sell this guy???
Mark
Posted by Peter Mork (Member # 1336) on 07-17-2004, 12:24 AM:
Simple thing to try: If you have used the clutch to disengage the motor during a print breakdown, when you re-engage it, it may not seat properly, and the drive shaft will slip and won't drive the idler wheel, and you get the effect that Jack described. Try just grabbing the motor and pushing up on it. It may work.
Posted by Manny Knowles (Member # 1171) on 07-17-2004, 02:57 AM:
Had this problem on a Christie platter once -- was not leveled properly when installed.
Had this problem with ORC platters a lot -- no in-between speeds, only on/off which resulted in stop-n-go motion on the outer reels. The light weight of that small amount of film was no match for the lurch of the ORC platters. This was a short-lived headache a while back but IIRC the fix was either service the motor, install new payout potentiometer or both. The REAL fix was when we upgraded to Christie platters.
By any chance, does the print in question have a permanent bulge?
I've been out of the tech biz since February but I don't recall that many static problems of late. Maybe I was lucky.
Posted by John Hegel (Member # 628) on 07-17-2004, 03:53 AM:
This is going to sound odd, but out of the different platters I have run I like the super platters.
For me, the key to keeping the blue cfs's happy, was to time all of the decks exactly to the same speed. After the timing was complete adjust the variac so that when you start the show the dancer will almost hit the bottom shut-off limit.
I've seen this done wrong at another place... the whole staff thought it was normal to frantically run to the platter and slow them down when the show started.
When the show is running the dancer will sit at about 1/3 of the way to the top of its travel. By doing this when the micro-switch turns on it will slowly ramp up the pay out speed. When it turns off, the payout will cost (not stop) until it turns on again.
My old theater ran the platter like this for years and never had a problem. some people would tape an object to the deck at the very end of the tail to hold it in place, but we did not need to use multiple objects to keep the print from flying off.
Posted by Aaron Sisemore (Member # 145) on 07-17-2004, 01:13 PM:
quote:
I heard that all you guys at Cinema West drive Yugos.... :Wink: . Don't you have somrthing good in the warehouse you could sell this guy???
HAHAHA, Mark...
Unfortunately, all the AW3's and AW35's we have in storage are spoken for, going into all our new builds
-Aaron
Posted by Dominic Espinosa (Member # 2122) on 07-17-2004, 01:56 PM:
And praise you for not giving us any of those CFS monkeys in our booth
I had a problem with a potts platter (similar design) at one of the other theaters I worked at. Along the same lines, the "tires" were hard and slick in a couple spots, I figure something got on there or they were exposed in a couple areas but not others somehow, either way this caused oscilation. It never tossed a print but It did give me a couple scares until they got replaced.
Posted by Will Kutler (Member # 770) on 07-18-2004, 12:43 AM:
I disagree with Brad concerning aluminum rollers.
Actually aluminum rollers would probably be less expensive tomanufacturer then the plastic. It can take maybe 10 minutes to construct a 3-D solid model on SURFCAM, maybe an 1 1/2 hrs tops to generate a CNC program and set-up the cnc lathe and maybe 2-3 minutes per roller tomanufacturer....probably less time. Sure, the "shot time" of a plastic injection mold can shoot out 24 pieces every 15 seconds or so, but the cost and maintenance of the plastic injection mold and all the set-up regarding plastic injectiomn molding would probably make aluminum a better choice.
Plus, aluminum rollers are soooo much easier to clean, especially when some idiot has gooped Lubriplate all over everything!
Posted by Brad Miller (Member # 2) on 07-18-2004, 12:48 AM:
quote: Brad Miller
*The aluminum rollers don't do anything. Save your money.
Pay attention, Will. He was asking about what affects the tossing of prints, not what is cheaper to actually manufacture.
Posted by Joe Redifer (Member # 3) on 07-18-2004, 01:25 AM:
quote: Will Kutler said:
I disagree with Brad concerning aluminum rollers.
Well, you did work for Century, right? They love those things there. I had a tour of a Century theater a few years back and they had one of them in each brain, and the prints were still all very staticy. The manager swore up and down that they helped, but to me it looked like they were trying to piss on a forest fire to put it out.[av=k]
Posted by Dominic Espinosa (Member # 2122) on 07-18-2004, 04:27 PM:
quote:
Plus, aluminum rollers are soooo much easier to clean, especially when some idiot has gooped Lubriplate all over everything!
I hope you hog tie (using leader tape or a good sturdy rope) anyone who thinks greasing rollers is a good idea...
I've spent the last month cleaning the brains at my theater, prior to my hire the projectionists greased all the brains and some of the takeup clusters (we have a3w's) with SuperLube...Although some had much older grease which was hard as a rock in some areas. What a mess it was.
Posted by Brad Miller (Member # 2) on 07-18-2004, 05:01 PM:
I think that's the one thing Will and I agree on. When new platters arrive at a location, the very first thing that should be done is the Lubriplate tubes located and then taken IMMEDIATELY to your vehicle for disposal at your home/hotel room. You don't even want to toss them at the construction site, because someone might pull them out of there and use it! Lubriplate is evil.
Posted by John Hawkinson (Member # 1135) on 07-18-2004, 08:35 PM:
So, what actually "went wrong" with Lubriplate? I mean, is it a product that works OK for some kinds of lubrication and just is really bad for moving parts like in projectors? Or is it 100% always bad in every situation? Why do some manufacturers recommend, etc.?
Is it just a case of a company marketting a substandard product, or is the picture more complicated?
--jhawk
Posted by Peter Schoell (Member # 919) on 07-18-2004, 09:35 PM:
I used to have a couple of CFS platters that did the same thing a 2 or 3 times a year. Like John said, you have to watch the timing. For some reason the vari-ac on my platters would always get out of adjustment and sometimes the motors too.
Too often when one platter is turning too fast the speed will be corrected by creating more pressure between the disc and the motor, this will take its toll on the motor bearings.
The timing procedure is outlined in the manual. Basically you need to loosen the center motor to a point where its just making contact with the disc and the disc will turn when the yo-yo is in the setup position. Then adjust the vari-ac to a point where the platter turns about 27 rpm ( I usually shoot for 6 or 7 rpm in 15 seconds).
The final step is to adjust the top and bottom discs so their speed matches the center one.
I fixed the whole problem by replacing the CFS's with Strongs.
Posted by Ken Layton (Member # 133) on 07-18-2004, 11:34 PM:
Lubriplate is great for certain applications, but not in the projection booth.
Lubriplate is the lubricant of choice in the coin operated machine industry. I use it all the time on coin chutes in pinball/video games and sliding lock linkages in payphones.
Lubriplate was actually recommended in Rowe & Rockola jukeboxes and Automatic Products "Smokeshop" cigarette machines.
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