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Author Topic: Christie AW3 Take-up Issue Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 01-10-2006 01:28 AM                     Didn't know it would stop spinning on PAYOUT. Ok, here is what I believe is happening. Your motor card is simply not making a good connection. Verify this and be prepared to change out that entire motor card receptacle. To test this, set the platter spinning with something holding the payout arm running at a decent speed. Now carefully wiggle the speed control card for that deck. Does it studder and drop out? If so, you will have to change out that entire card receptacle. (The pins on that are easily damaged if someone "crams" their multimeter probes IN them to set the led resistance.) For an interim fix, you can wedge a small piece of stripped end wire in between the contacts and the card as you insert the card. (Don't use stranded wire.) Be forewarned, this "fix" sucks and shouldn't be used any longer than you have to as it is NOT 100% reliable, but is 95% reliable and will at least give you some use of that deck until your replacement motor card receptacle is installed. This actually makes more sense than you would think, because the entire platter system will have more "wobble" to it upon startup where both discs are spinning at top speed and that slight shaking can cause the card to not make a good connection if the contacts have been bent or abused. As the decks spin slower and slower, there is less shaking going on and also you have more delay time if there is a brief dropout before the takeup arm would "drop".  |  IP: Logged Dominic Espinosa Phenomenal Film Handler Posts: 1172 From: California, U.S.A. Registered: Jan 2004 posted 01-10-2006 02:46 AM                     quote: Thomas Dieter That's why I cleaned the washers and shaft thinking if there was a peice of metal or dirt that didn't allow the deck to spin properly. It'd have to be something pretty big, otherwise it would just destroy the bearings and trash the washers/deck. If Brad's theory about the loose card(s) doesn't pan out I'm thinking make switch. I've heard of such a problem with an AW3 at another location our tech services.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 01-10-2006 10:48 AM                     Agreed, but he said he changed out everything but the wiring already. This is the only thing left that I can think of which could cause that problem. Tick, tick, tick, tick, tick....  |  IP: Logged Thomas Dieter Expert Film Handler Posts: 234 From: Yakima, WA Registered: Jun 2004 posted 02-17-2006 05:56 PM                     Okay, our tech and myself have looked into the problem again, and still can't pan this one. We've wiggled the cards slightly and vigerously, and nothing is being picked up as a break in connection. Nothing. I did take and have to break a movie down from that platter though using the feedout assembly. I used my frame counter to give the tention and act as the bottom roller on the m.u.t and it wrapped the film firmly. What happened was we had a print of rent that had a slight strech on the film, but nothing that caused a problem to the point of removing it. While moving it to another platter to break it down as it was in the house that we are having a problem with, due to the strech, it cause the print to fall apart in that very spot. So to break it down, I ran it through the feed out assembly with no problem. The feed out was able to keep up with the m.u.t with out falling behind. What do you think the problem might be with this new information?  |  IP: Logged Dominic Espinosa Phenomenal Film Handler Posts: 1172 From: California, U.S.A. Registered: Jan 2004 posted 02-18-2006 03:22 AM                     Forgive me if you've already tried this, I just skimmed the refresh a bit. Have you tried the make-up switch yet?  |  IP: Logged Thomas Dieter Expert Film Handler Posts: 234 From: Yakima, WA Registered: Jun 2004 posted 04-06-2006 02:08 AM                     I can finally close this thread. Just this evening after we closed down, I tried my final attempt at fixing this problem. We stopped having problems with the feed out of the platter, and were able to use it as feed out platter, but with 2 prints in that house most of the time, that's not the solution. I looked into it more, and checked the take up assembly, and compared it to the two working platters. The take up was acting late when you start the platter by about an inch, and was stopping about half an inch early, if that made any sence to you. I've posted a small diagram to explain what I was talking about. So I called my tech, told him what I found, and worked with him on the phone. Followed his procedures to timing the platter, and told him what I found. Turns out that the card that controls the LED intensity seemed to have gone bad. I was unable to adjust the current for the bottem platter. Atleast I wasn't able to turn it down. I ordered two new cards, and put one in, and voila, problem fixed. I don't know how we missed that, but all I can say is i'm happy it's over and done with. No more moving prints cause we split the house. I'm going to take a better look at the card tomorrow and see if there is any visable damage next to that trim pot.  |  IP: Logged Michael Schaffer "Where is the Boardwalk Hotel?" Posts: 4143 From: Boston, MA Registered: Apr 2002 posted 04-06-2006 05:05 AM                        We all thought you had already tried to retime the platter decks. That anomaly should have been noticed then, then it wouldn't have become such a big "mystery".  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 04-06-2006 10:59 AM                     Fully agreed. Timing the platters includes calibrating the led card. Out of curiosity, what was the ohms rating on the multimeter for the bottom deck that was throwing prints?  |  IP: Logged Thomas Dieter Expert Film Handler Posts: 234 From: Yakima, WA Registered: Jun 2004 posted 04-06-2006 11:15 PM                     I was under the impression that we had already tried that. When I took and pulled the card, I noticed the Ohms setting before pulling it and attempted to set it. On the setting of 20M it was reading 1.25+ I checked the other two decks and they were set at 0.45ohms or there abouts. The Bottom deck would not go any lower than that. I've yet to look at the card I pulled, but it does have brown spot on it. The techs settings are done at this. LED Intensity: 0.45OHMs Low Trim Pot set at 20 Degrees: set to just the point the motor hums or growls. High Trim Pot set at 70 Degrees: set for 20 RPMs. Recheck the Low Trim Pot, and tweek as needed. Recheck the High Trim Pot, and tweek as needed. I set all the platter to the above settings, and had not 1 single problem today. The Payout worked perfetly, and the take up worked just as good if not better. [ 04-07-2006, 01:39 AM: Message edited by: Thomas Dieter ]  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 04-06-2006 11:26 PM                     Well your tech is partway there on ideal timing at least.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 04-08-2006 02:08 AM                     Thomas - did your tech use a 'platter tach', or just count revolutions of the deck?  |  IP: Logged Eric Robinson Jedi Master Film Handler Posts: 538 From: Santa Rosa, CA Registered: Jan 2005 posted 04-08-2006 12:06 PM                     Sorry guys, I'm totally confused. This implies setting the LED intensity to 70 ohms quote: Monte L Fullmer 12.6K ohm on the LED resistance? (OUCH!) Should be down to 70 (-/+ 2) ohms with the pointer on the 70 degree mark..and use a digital VOM meter. -Monte While the Christie manual specifies 70,000 ohms quote: Set film position sensor over 70 degrees mark on feed control plate... ...If necessary, adjust LED intensity to obtain approximately 70 Kohm ... and now, from this topic we learn quote: Thomas Dieter On the setting of 20M it was reading 1.25+ I checked the other two decks and they were set at 0.45ohms or there abouts. Should I be confused or not?  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 04-08-2006 02:43 PM                     Okey, so I forgot the "K" in the ohms reading.. ...I go by what the book says...I've never had any probs with using the 70k ohm, 20 and 70 degree settings. .. BUT.. I also have a platter tach to get accurate RPMs per resistance settings.. Monte  |  IP: Logged Thomas Dieter Expert Film Handler Posts: 234 From: Yakima, WA Registered: Jun 2004 posted 04-08-2006 03:04 PM                     Monte, I don't know if he used a "Platter Tachometer", but he did use a Tachometer. No, I myself took and had to count the revolutions by eye. Wasn't that hard, but it did get tedious. Took me about 15 mins to do each theatre, depending on how long it took to set the LED cards. Eric, When Monte said the LED card should be set to 70 OHMS, he was refering to 70K OHMS, just like the Christie Manual says. Everyone seems to have their own setting to set Christie Platter cause from the sounds of it, Christie has no idea how to time time as they have changed the setting 3-4 different times. On my multi-meter, the setting is at 20M, for 450K OHMS at 20 Degrees reads 0.45. When I took the reading of tha card before pulling it, it was reading 1.25 or higher, meaning it was set WAY to high (something like 1250K OHMS), and it wouldn't come down. It would go up, but not down. --Tom  |  IP: Logged Eric Robinson Jedi Master Film Handler Posts: 538 From: Santa Rosa, CA Registered: Jan 2005 posted 04-08-2006 03:52 PM                     Sigh of relief I had one of those sinking feelings that I had been doing it wrong all this time. It is not uncommon for me to discover this once and a while when reading these forums. I have been using the Christie method 70K at 70% which seems to work quite well. I use a tachometer and set RPM's to 22 RPM at 70%. I do have one platter system though; a Christie mini-wind which has caused problems for me since day one despite repeated calibrations, circuit board replacements, variable density, and LED assembly replacements. It seems like it always needs a little fine tuning on the high speed motor pot while its in use. The platter size is smaller too which I take into accomodation when using my RPM gauge.  |  IP: Logged

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