Is this a good thing...or a bad thing?

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2 Time ICWF Champion

The best solution is posted in a page on Christie platters in the "tips" section (of which I desperatly need to update). Just look for the part in there about "grooving" the platter decks.

For those people with decks that can not be grooved in this manner (say SPECO and Strong for example), Kelmar is now selling a blue rubber mat which looks interesting, but I have not personally tested it so I hesitate to definitely say it works well. There are also other solutions like the round sheet of hardwood with asphault strips on them, but I do not like those for they constantly bump the feed arm and I wouldn't want the edge of my prints dragging over what is essentially sandpaper. (Although in all fairness I have heard positive reports from the field.)

Brad, those boards with the asphalt strips I have at my theater. I used them once, then decided never to use them again, because on the speco platter systems I couldn't get the film to ride on them properly, and that was after adjusting the takeup roller as high as it would go.

We bought several AW3's from them about a year ago and I spent the better part of a couple hours peeling tape from the decks and cleaning the decks (FilmGuard to remove the adhesive goo, followed with soap and water to clean the FG residue)...

I screened their new print of Jason X, and it looked fine. Then, I screened a little bit of Clockstoppers that they have had for a little over a month. There were some pretty nasty scratches on the non-soundtrack side of the film--right side on the screen. So, I suppose those could be from the grip tape...but then they should have been on the Jason X print too.

Oh well, thanks for the advice. I'll pass it on to the GM there and we'll see what we can do.

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2 Time ICWF Champion

I have 5 each AW3's in Stanwood, and I never saw these machines come even close to throwing a print. Of course, these platters are badly scratched from previous operators that apparently did not care about taking care of the equipment.

However, I have 3 each A-3's in Anacortes that get a little tempremental, and the film does shift off center sometimes. Perhaps a re-time would take care of that problem. I use microswitch pay-out heads which are the absolute worst for stability, but the best for reliability. They do like to "whip" upon contact closures of the micro-switch.

I have 3 each CFS machines in Oak Harbor. These 20-year old machines are more forgiving about "whipping" since they had a ballast resistor (I think it is a 10 ohm 25 watt rating, and this resistor is physically inside the motor housing) across the micro-switch contacts. But they were much more critical in timing. As old as they are, they seem to run fine for the most part. I seldom have reports of the prints shifting off center, but I would guess that has something to do with the steep crown the platter decks have.

For years, I had ran a bunch of older Xetron platters (the XNR series) and never had a problem of any kind involving tossing or shifting prints.

As a note, many projectionists/operators blame the pay-out head for feed problems, such as they won't stay up with the demand or they overshoot and hunt excessively. With the A-3's, (Strong and Potts) the CFS and old Potts and Potts-built ORC's, the problem may not be with the pay-out head. It is more often the take-up causing the problem.

How could that be?

Simple....The take-up dancer controls the variac which in turn sets up the operating voltage for both the take-up and pay-out motor. If the dancer is riding high, the pay-out will probably fall behind and cannot stay up with the demand. If the dancer is riding too low, there may be excessive over-shooting and hunting. Now that will enhance the danger of the print leaving the platter dish and throwing itself on the floor, bashing the pay-out head to smithereens in the process.The only thing I can think of is when an AW3 tosses a print, it is because there was a control module failure that would allow full power to the drive motor.

AW2's or AW1's, are obsolete. I don't think Christie supports them anymore. If that be true, junk them out when they start giving you headaches.

So, what are there so many problems with platters throwing prints? Are people waxing their decks to make them look real pretty? If they are, they will definately toss the print on the floor.

Maybe the projectionists or operators are they using the wrong formula to keep the decks clean.

The light bulb is on.....Input, please.

Rant Mode off.....

Seriously though, I've never had a problem with the CFS platters throwing a print. But they do have a lot slower "reaction time" than the Christie AW-3's i've used in the past. So much so, that we usually try and kick-start the platter by hand when starting the film, rather than just letting the film wrap around the brain before unwinding. Once its up and running though, there isn't much of a problem.

Paul, what did you mean by "I would guess that has something to do with the steep crown the platter decks have"?

If you use a straight-edge, you will observe a crown in the dish almost 3/8 of an inch difference form the center and the edges. If you use the "Ole Eyeball" method, you can still see the crown.

As far as helping the platter along on start-up, I have mixed feelings about that. The only thing I don't like about doing it that way is that it does not give enough time to insure the focus, mis-frames (lots of those in Oak Harbor), etc.

Have faith in those platters. They will take care of themselves, and just make sure things are looking correct on the screen.

And that right there is why the Christies if not properly timed will throw a print through the wall. All it takes is a tiny knick in the platter to grab at the film during payout (which is of course worse as you get toward the end of the movie) and the arm will swing violently from say the 20% speed it was running happily at and slam all the way over to 100%. Whip, slide, kachunk, oh shit! This is why I do not like the timing instructions in the Christie manual. The platters run too jerky when they are timed that way. If you time them my way and groove the decks, I think you will find that print tossing on a Christie will be a thing of the past.

P.S. the new "auto-timing" kit that Christie is putting out is crap. They WILL hurl prints on you! It is impossible to achieve the smoothness of the old graduated filter and led with this new infared/linear "upgrade". I know some people like them, but I find they make the problem worse.

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Paul, why do you say the microswitches are the worst for stability? I thought you liked them.

Even if the micro-switch set-up tossed a print on me (0 times in 20 years), I would still prefer that record rather than all the shows lost over the same period of time due to some damned electronic-based linear pay-out control deciding it is time to go to lunch.

I wonder if the high failure rate of the linear controls might be due to under-design and surge current when switching the motors on and off with the dancer raised? Or, even worse, raising the dancer before turning off the motors....That should be looked into. That is one helluva surge if, for some reason, the pay-out arm is flopped to the full-on mode when the dancer is raised.

Engineers like Steve Guttag as well as others might be able to calculate the strength of the surge, and whether or not the triac or SCR (or whateverthehelltheyuse)in those whimpy pay-out controls can handle the hammering.

Maybe it is also due to the LED's losing their poop like some basement digital basement readers....

I find it sort of odd that those linear pay-out head controls have a relatively short life as compared to the micros.