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Topic: "Bump" On Christie Platter

Sean McKinnon
Phenomenal Film Handler

Posts: 1712
From: Peabody Massachusetts
Registered: Sep 2000

posted 09-30-2000 01:38 AM

The christie AW3's that I am forced to use have the stupidest take-up ring design. Having only used Strong/Potts Platters for 2 years I am used to building prints tightly onto the rings with no problem on the christie design however the space in the ring causes the film to create a "bump" if built tightly. This "bump" causes the worst brainwrap/platter fling I have ever seen!!! This is driving me nuts does anyone know how to build prints on these platters so that they are not loose as hell? Its a pain to move them when they are that loose and I think it affects the focus of the print if it is not built at a constant speed? If anyone can help me solve this problem i would appreciate it!

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99

posted 09-30-2000 02:13 AM

You must be trying to apply backtension pressure on the supply reel during loading...a big no no. We've had a similar discussion on this about breakdown. No human can keep truly constant tension. Let the machine do it's job as it was intended (meaning without your adding any tension) and you won't have any problems.

The solution is to build the film on the deck where it is to play it's first show. A print will be most susceptible to damage before it has been ran once, so building on "the closest platter" and then moving the print is a very bad idea in the first place.

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Sean McKinnon
Phenomenal Film Handler

Posts: 1712
From: Peabody Massachusetts
Registered: Sep 2000

posted 09-30-2000 06:27 PM

No, this is what happens when I let the machine do its job I do not apply back tension when building. Also I try to build on the platter that it will be running on but this is not always possible.

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Jon Bartow
Master Film Handler

Posts: 287
From: Massachusetts
Registered: Nov 1999

posted 09-30-2000 07:21 PM

I have had a similar problem with AW3R's and the MUT's before. The problem turned out to be the bearings in the motor in the MUT were shot, therefor providing A LOT of tension. Also, check the bearings on the spindle. It also makes a huge difference if you don't have the thing cranked up to full speed, halfway is plenty

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Scott D. Neff
Theatre Dork

Posts: 919
From: San Francisco, CA
Registered: Oct 1999

posted 09-30-2000 07:35 PM

Halfway is plenty... tell that to ANYBODY who's ever used a Potts or Super Platter MUT before.

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Mike Jones
Expert Film Handler

Posts: 108
From: Birmingham, MI, USA
Registered: Jul 2000

posted 09-30-2000 09:17 PM

We use Christie AW3s, we've got the green rings with the space cut out. We use christie MUTs. rarely do i have problems with prints being so tight that they "bulge." Some prints seem to wrap tighter than others. some are extreemely loose. On the majority, when i assemble a moive it comes out tighter than most. I run the MUTs at full blast... i don't know what to say, ours have been fairly trouble free. ??

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Sean McKinnon
Phenomenal Film Handler

Posts: 1712
From: Peabody Massachusetts
Registered: Sep 2000

posted 10-01-2000 12:17 AM

We have 3 different mut's all of them are a bit "Sketchy" full blast on one is equal to half on another. I am responsible for all the work on thursday nights and in order to get out of the theatre by 1 or 2 am I have to go as fast and be as efficient as I can. I think it may be the spindle on the MUT's I will check it out.

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Randy Stankey
Film God

Posts: 6539
From: Erie, Pennsylvania
Registered: Jun 99

posted 10-01-2000 05:56 PM

When you get a "camel hump" like that it's almost always a sign of too much tension.

Do you build up on 6K reels? They get "tight" as you get down to the last. I take out the drive pin on the spindle, leaving the reel to spin freely on the shaft. I hold a shop rag against the side of the reel to supply tension.

Second, is your MUT motor working properly. I just walked into a booth, today, and they told me that their MUT was pulling the film too tight. I found the bearings on the motor were shot. Whatever the cause, turn the spindle of your MUT by hand. You should be able to turn it pretty easily. There should be resistance but you shouldn't have to HORK on it either.

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Sean McKinnon
Phenomenal Film Handler

Posts: 1712
From: Peabody Massachusetts
Registered: Sep 2000

posted 10-01-2000 11:45 PM

well, I think that all the bearings are probably shot (how easy is this to fix) someone also said today that they heard the GM say something about the last projectionist adjusting the tension on the platter and thats why this does this????? does this make sense???? sorry all but I miss my Potts Alpha Platters.

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Randy Stankey
Film God

Posts: 6539
From: Erie, Pennsylvania
Registered: Jun 99

posted 10-02-2000 04:04 PM

Did you check? Try to turn the spindle by hand. Also reach underneath (with the thing unplugged) and try to turn the motor shaft. Check all the parts in the "
drive train".

If the motor is bad, it's just a "Nut 'n' bolt job". Can be done in 15-20 minutes by a reasonably intelligent person.

Just order replacement parts...

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Sean McKinnon
Phenomenal Film Handler

Posts: 1712
From: Peabody Massachusetts
Registered: Sep 2000

posted 10-02-2000 10:04 PM

I checked and it is kind of difficult to turn
I was wondering, does it make a difference how you have the reel put on the spindle. To avoid twisting the film I sometimes have to put the reel on so the film is coming over the top of the reel instead from underneath?

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Randy Stankey
Film God

Posts: 6539
From: Erie, Pennsylvania
Registered: Jun 99

posted 10-03-2000 01:33 PM

You should thread it the way it says in the instructions.

If you have to twist the film to get it to go onto the platter, then rewind the reel and make sure you wind it in the right orientation. You ought to be inspecting your prints before you build anyway. When you do, that is the time to also check the winding orientation.

If you are building onto a 6K reel, then you are sort of inspecting and building at the same time. Again, check your winding orientation now to save you the trouble later.

As far as the Make-Up table goes... You ought to be able to turn the spindle with one hand. If you can't, get down on your hands and knees. (Or flip the thing on its side. ) Look underneath and make sure all the parts under there are in good working order.

If you really don't want to do this or if you just don't 'trust yourself' not to F*** it up then call someone who does and explain the whole thing to them. It's really not a big deal, though.

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Rory Burke
Expert Film Handler

Posts: 181
From: Burbank, CA, USA
Registered: Jun 2000

posted 10-03-2000 01:45 PM

I think it might be also caused by the speed at which you are building at. One should never ever build or break down at full speed.
Most scratches are caused by the film hitting the edges of the reels or whacking the edge of the platter or trying to come off the rollers. 6000 foot reels and AW3's are usually a bad mix i have come to find. Those reels can get soo heavy that those motors can burn out on you. A slower constant feed can help you better keep track of you print while you build it and make adjustments for tension etc more easily and with out risking damage to it.

Rory

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Sean McKinnon
Phenomenal Film Handler

Posts: 1712
From: Peabody Massachusetts
Registered: Sep 2000

posted 10-03-2000 05:01 PM

Thanx for all the help Ive figured out that it is a problem with the MUT and also the last projectionist making adjustments that he was not supposed to

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99

posted 10-04-2000 12:35 PM

F.Y.I. On later models of the Christie MUT (or a replacement speed control) there is a small adjustment that can be turned to increase speed for loading. Back before I got the fabulous Goldberg print reel, I would have these set to max and never load faster than 3:00 from 6000 foot reels. For larger reels, I say no faster than 1:00 (actual speed will of course vary just a touch).

I recommend to NOT load with the supply reel spinning clockwise (as pictured in the manual). I've seen prints that were left unattended jump the lower roller on the MUT and cause significant damage. Also if there is a bounce to the film, you can have intermittent marks on it as it bounces away from the roller and against the bracket. The best way around this is to build up so the reel turns counterclockwise as it is loading. This gets a better wrap of film around that roller and provides a smoother roll.

If for whatever reason prints MUST be built onto one designated platter and carried up ladders and such to their final destination, a small weight can be added to the motor bracket on the MUT to increase loading tension just slightly. I've never had a problem with an AW3 putting too much tension during buildup unless someone was standing there holding the reel. It sounds like the bearings are definitely the problem on the issue above.

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