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Topic: change platter from micro switch to phase control?

Tracy Bellar
Film Handler

Posts: 72
From: Sciotoville, Oh.
Registered: Mar 2005

posted 04-04-2005 01:37 AM

I'm working with Strong 35-A3's and A5's. I've heard of the phase control and was wondering if the platters I use can be converted to phase control. Is there more to it than changing modules(Brains). Does the phase control really run better than micro switch. Is it worth the trouble?

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Aaron Sisemore
Flaming Ribs beat Reeses Peanut Butter Cups any day!

Posts: 3061
From: Rockwall TX USA
Registered: Sep 1999

posted 04-04-2005 02:18 AM

STAY WITH THE MICROSWITCH!

I am thinking of changing all my phase control brains to the microswitch.

The phase controls work fine for a while then get slower and slower to respond, unlike the microswitches.

-Aaron

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-04-2005 02:25 AM

There's arguments both ways: One can say that phase controlled brains are the way to go, and one can say that microswith brains are the way to go. I've seen both.

Main reason of users using microswitch is that with the vacuum motors that these platters uses are very sensitive to variations in voltage in the AC line. One volt difference in the 120VAC line, either way, can cause the platters to go faster, or go slower.

Phase controlled brains, in as much as they pay out film in a continous fashion, will be sensitive to this voltage variations in where the one volt drop will cause film windage to wrap around the roller ring a good two times while the film is being paid out, due to the slight slower rotation of the platter. One volt more will cause the platter to "stop and go" due to the faster rotation of the platter.

Microswitch brains are not sensitive to this. It's a simple "On and Off" situation-no matter what the voltage variations are.

If you're using microswitch and happy with it, stay with microswitch. Yet, if not and you want to try phase control, plan on spending $170.00 per module from Strong.

Installation of Phase control modules is quite easy. Two things that must be done for the conversion: take out the microswich hardware, and move the inner guidance roller to the outer hole on the control plate. The wires from the control plate plug must be attached a certain way (in phase) with the module. Wires crossed and the module will not work. When installing the module, one screw is a regular pan head and the other is a phillips taper head. This allows alignment of the module to the arm. the payout arm where the film feeds through must be at least a half inch from the stop roller for the module to activate. Any later, and wraps will be prominent. Earlier and one can have payout problems.

I've seen both in operation. One "indie" house that I service had phase controls and they work like a charm-no wrapping, no early payout problems. Film feed dead center to the brain.
Microswitches can be problem free as well, if they are aligned correctly as well as above, but in time, the switches do wear out and short across where brain wraps are common, (which is a good time to install the Strong Wrap Detectors that is available for the A-3/AP-3 and the AP-5 units) then it's time for a microswitch changeout.

I get my microswitches not from Strong, but from Grainger (the 6X-284 switches) which are 10 bucks cheaper than the ones from Strong.

Hope this help you out. Good luck-Monte

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Tracy Bellar
Film Handler

Posts: 72
From: Sciotoville, Oh.
Registered: Mar 2005

posted 04-04-2005 03:14 AM

thanks! Right now we are using one module per print and changing every show. I'm trying to convince the owner that we need more modules because of wear. Moving the thing every show wears them out to fast. I liked it before when we had a dedicated module for every platter. So if We get extra modules mabey we could try a few of the phase to try out. mabey dedicate two to a three tier and see how they work. I guess going total phase would be too expensive anyway just to convert. Since I have a few warped platters it's really been causing a headache with payout. I was hoping the phase would be steadier feeding out film and not speed up and slow down so much like the warped platters.

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-04-2005 05:13 AM

quote: Tracy Bellar
I was hoping the phase would be steadier feeding out film and not speed up and slow down so much like the warped platters.

Now, you have a BIG, BIG problem there! ... Warped Platters!

Unfortunately, neither microswitch, nor phase control will solve this problem.

What's happening is that when the control arm opens up, the motor takes off on full speed, bringing up the "W" film accumulator to the top which brings the motor to a FULL STOP. Then when the platter has stopped, yet the film is still being delivered to the "W" film accumulator, the "W" film accumulator will begin to drop causing the motor takes off again at full speed, causing this oscillation of stopping and starting and eventually print damage due to the sinching of the film across the "W" film accumulator, and pulled lower guidance rollers from the projector.

One theatre that I know of was playing "LOTR-III" and as big as that print on the deck was, the deck was slightly warped, cause tremendous oscillation, and pulled lower guidance rollers on the projector. When the film was finished, I did my best to flatten out the warpage on that platter by taking the platter off, turn it upside down, and literally pressed on the warped part to flatten it out some.

Best thing is to do is either: straighten out the decks as flat as possible, or replace the decks.

What causes decks to be warped is a most common, and a very sinful and taboo practice, and that is: placing the splicer on the deck and splicing on the decks due to a bad splice or break. (if Brad Miller EVER sees you splice on a platter deck, he'll cut your hands off..lol)

One "HAMMERS" down on the splicer handle thus pushing down on the deck, causing the deck, which isn't the sturdiest made due to the "spider" assemblies below the deck and thin aluminum, to bend down at the end. And this area is where the drive tires of the platter motor are located at below. The motors, then to move up and down due to the warpage and lose grip on the underneath surface of the deck causing this variation of platter speed and eventual oscillation due to the oscillation control of the "W" film accumulator.

Please heed these words of advice of repairing your decks first before doing anything with the brains.

-thx and good luck-Monte

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 04-04-2005 05:37 AM

quote: Monte L Fullmer
What causes decks to be warped is a most common, and a very sinful and taboo practice, and that is: placing the splicer on the deck and splicing on the decks due to a bad splice or break.

Actually moving the whole deck to move a print also creates warped decks, wspecially if it is done wrong. I cut off proples arms if they are caught moving decks!

quote: Aaron Sisemore
I am thinking of changing all my phase control brains to the microswitch.

Phase control sucks big time..... You couldn't get me to use a phase control platter if you held a gun to my head! Installing the correct type of microswitch is the key to having a smooth running platter.... warped or not. Unless they are really badly warped they can usually be straightened anyway. Beyond that you will need a wrecking ball to tear the place down and start over. Be sure to buy Christie platters for the next building [Big Grin]

!

Mark

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Dustin Mitchell
Phenomenal Film Handler

Posts: 1865
From: Mondovi, WI, USA
Registered: Mar 2000

posted 04-04-2005 10:04 AM

It seems we go around and around on this every time the topic comes up-I am perplexed by all the phase control complaints, the units I have work just fine. No drifting, no slowing, steady payout.

However, Monte had it wrong, if I recall the phase control upgrade is $250 from Design Manufacturing, not $170. Going by Marks recomendations for microswitches and how often to change them you could keep a microswitch deck running for 62 years for the cost of one phase control box.

So...yeah.

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Ken Layton
Phenomenal Film Handler

Posts: 1452
From: Olympia, Wash. USA
Registered: Sep 1999

posted 04-04-2005 10:11 AM

Are the decks actually warped? Or do they just "wobble?"

If you have the older decks with the "spider" thats attached with pop rivets then the rivets have come loose and developed slop. Drill them out and replace with bolts and Nylock nuts.

If there's a pronounced wobble it could be the deck bearings are worn or the center post nut is loose (it needs to be very tight). Sometimes the deck can appear to be warped it the screws attachint the deck to the "spider" are loose or missing.

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Richard May
Phenomenal Film Handler

Posts: 1057
From: Floral Park, NY USA
Registered: Aug 2004

posted 04-04-2005 10:42 AM

I love the phase controls brains. They are costly though to replace. In the 10 years at my theater, I have replaced about 4 phase control units that went bad. That is out of 4 theaters. The phase control is definitely a smoother operation. The only problem I have had is what Monte said. They are very sensitive to voltage fluxuations. But that has only happened rarely to me. The other reason I don't like the microswitches is that when I go on a call because of a problem with them, it is usually because someone bends the arm on the microswitch and it screws up. You can't really mess up the phase control units.

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Tracy Bellar
Film Handler

Posts: 72
From: Sciotoville, Oh.
Registered: Mar 2005

posted 04-04-2005 02:47 PM

The warped platters are a problem I inherited. It was because of moving the platter decks. When it would get stuck I guess they would push up harder. I've put a stop to moving the platters. Also, too fast at building prints has been halted. after working with them a little I've been able to get most of the platters running well enough. I only have two still giving a problem. It took months of explaining what was happening to get this activity ended. The people in the booth had no idea of what damage they were doing.

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Brad Miller
Administrator

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

posted 04-04-2005 02:58 PM

quote:
Phase control sucks big time..... You couldn't get me to use a phase control platter if you held a gun to my head!

How about if someone paid you $50,000 per phase control platter, installed? Money talks, eh? [Razz]

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-05-2005 01:40 AM

quote: Tracy Bellar
The people in the booth had no idea of what damage they were doing.

...then it's time to have them exit the booth premises,if they don't listen (unless they are stuck on old habits by the manager, then this is a difficult one to solve. For you have to get to the manager first and show him what is really going on, then he can show the others on correct procedures) ,or find somebody new who will listen and be trained correctly to what you have to say...

..sounds like you got a bit of overhauling to do there on these transports then. Good luck.

-Monte

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Carl Martin
Phenomenal Film Handler

Posts: 1424
From: Oakland, CA, USA
Registered: Feb 2002

posted 04-05-2005 02:29 AM

quote: Monte L Fullmer
What causes decks to be warped is a most common, and a very sinful and taboo practice, and that is: placing the splicer on the deck and splicing on the decks due to a bad splice or break. (if Brad Miller EVER sees you splice on a platter deck, he'll cut your hands off..lol)

gosh, i hope he doesn't catch me! when i break down (the only time i use a guillotine splicer anyways) i do the splicing on the platter deck because it's by far the easiest way to keep the film ends under control and not risk scraping the film on something and keep it off the floor. when i do the punch'n'cut, i press down on the splicer handle while pressing up on the bottom of the platter deck. i'd say the net force on the deck is far less than that incurred by moving a print.

and doesn't everybody splice on the deck while changing out trailers?

carl

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-05-2005 03:25 AM

quote: Carl Martin
doesn't everybody splice on the deck while changing out trailers?

(LOL) Hell, yes. Most of us do. But we are as smart like you are in doing the same tactics that you use. We take it easy and carefully!

Just that some of the *ahem* "other operators" HAMMER down on the handle when doing the punch and cut method and having the splicer (usually the Neumade 35SS models) at the edge of the deck where it's the weakest, when doing the HAMMERING and PRESSING technique-due to their splicers are so full of goo and gum from neglect of maintenance.

-Monte

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