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Author Topic: Static and CNR Antonio Marcheselli Phenomenal Film Handler Posts: 1260 From: Florence, Italy Registered: Mar 2000 posted 12-20-2003 08:20 PM                        Hi everyone I'm having some static problems, our humidity is too low (we are asking for hudifiers). Some time ago I found that many of the CNR platters were not connected to the column. In other words, if I check the resistance between the platter and the CNR column there was NO conducibility (ALL the column are ground connected of course!). Usually there is conducibility when platter is stopped but NOT when it is moving. I solved this problem before putting a special grease, with graphit in it. It is not the best for bearing but since the platters are rotating very slow and the graphis is very small it is not a problem. I started putting the grease with the help of a brush inside the bearing, without taking off the old grease. The result was time limited, after few weeks the problems came again. So I disassembled a platter, I take off the bearings, I cleaned them from the old grease and I put only the new grease with graphit. The result was perfect but again, time limited. I still have all of my platter nor ground connected while rotating. Is there a chemical product that increase the conducibility and it is suitable for bearings? Or any other suggestions... Thanks! Bye A  |  IP: Logged Max Biela Film Handler Posts: 89 From: Dortmund, Germany Registered: Sep 2003 posted 12-21-2003 02:49 AM                     Hi Antonio! What are your static problems? What about the Projector? There must be a few rollers that are grounded so you should not have problems like popping sound. The CNR Platters are very good in loosening sticking film layers, at least if they were not timed as stated in the manual (max. speed 60-65 RPM). If you set the max. speed to 35 RPM you get the best results because the platter still needs some time to ramp up to full speed. At 60 RPM, the film will wrap around the Pay out unit every time the arm gets pushed into full speed position. Normally if this happens there are the rollers around the Payout unit which protect the film from getting scratched, but if there is some film inside of those rollers which was pushed there by the other film layers wrapping around them, there is the danger for the film getting caught by the film which runs normally through the pay out unit... Solution: Time the platters at max. speed 35 RPM and you wont have this problem. Some time ago, Cinemeccanica sold an Anti-static "cleaner" (which was not a cleaner) for mounting it on (endless-loop) platters for working with polyester-film: I would not use anything with graphit on the bearings, think of make up or take down of prints! Max  |  IP: Logged Darren Briggs Master Film Handler Posts: 371 From: York, UK Registered: Dec 2001 posted 12-21-2003 06:17 AM                        Are all your platters effected this way? I find if a print becomes problematic, flip the take up orientation of the print, i.e. if you take up with the soundtrack up, on the next run, tkae it up with the soundtrack down, doing this for a couple of days normally settles the print down totally. Overnight you can try the THX greenhouse trick. Put a tub of water in the center of the plate and cover the print overnight. This can help loads in getting rid of static on the print. Ensure you leave a note on the plate, so that the next projectionist doesnt just rip the cover off and knock the tub of water over the print thought!!! In combination with the flipping of the print the static should not cause a problem. Darren  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 12-22-2003 01:28 PM                        Max Biela wrote: quote: Some time ago, Cinemeccanica sold an Anti-static "cleaner" (which was not a cleaner) for mounting it on (endless-loop) platters for working with polyester-film: The unit in your photo seems to be a corona discharge ionizer. High voltage AC on needle points in the unit ionize the air, making it conductive, so that any static charge on the film has a conductive path to ground. Similar units are made by Simco, Kinetronics, Meech, and other manufacturers of static control equipment. Properly used, they are very effective in controlling static.  |  IP: Logged Max Biela Film Handler Posts: 89 From: Dortmund, Germany Registered: Sep 2003 posted 12-22-2003 02:12 PM                     Hi John! Yes, but the Kinetronic also has 4 brushes to clean the film, the Cinemeccanica not. They are VERY useful with "old" polyester prints. Does anybody know if Cinemeccanica still sells these units? They look so nice on CNR platters I've also heard that Cinemeccanica sold a PTR-Cleaner along with CNR platters (I think they call it "Drypur or so..). Has somebody a photo of it? Were on the platter was it mounted? Max  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 12-22-2003 02:23 PM                     Drypur rollers were a completely different animal to PTRs as they picked up dirt and it then migrated through the (silly putty) to the centre core. It did require that the plastic strips be placed on them when not in use to prevent them drying out They were effecive at eliminating static and didn't complain about oil on the print They were developed in Belleville Ontario Canada and drypur is still in business there  |  IP: Logged Max Biela Film Handler Posts: 89 From: Dortmund, Germany Registered: Sep 2003 posted 12-22-2003 02:38 PM                     Hi Gordon, so if I understand you correctly you will have to change teh complete Drypur roller? Is there a website with more details about it? Max  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 12-22-2003 02:44 PM                     The rollers required replacement when no more dirt could migrate through the material or if someone left the bands off and they dryed out Last timeI contacted them it was Restoration House Film group Ltd Box 298 Belleville Ontario Canada K8N 5A2 (613) 966-4076 It has been about 2 or more years since I delt with them  |  IP: Logged Antonio Marcheselli Phenomenal Film Handler Posts: 1260 From: Florence, Italy Registered: Mar 2000 posted 12-22-2003 05:14 PM                        John, I have kinetronics on all of my platters. What do you mean with "properly use"? I have so low humidity and the print is so warped that the kinetronics brushes cannot touch both sides of the print itself... Bye A  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 12-22-2003 09:19 PM                        By "Properly Use", I mean that they are properly positioned to discharge the film in the most effective way, that the frames are properly grounded, that the corona points are kept clean and free of dust buildup, and that the high voltage power supply is monitored to be sure it is working well. If you are not careful, they can generate ozone. Get yourself some evaporative humidifiers, capable of putting a few dozen liters of water vapor in the air each day. If the film is "warped" with curl, you really are much too dry.  |  IP: Logged Max Biela Film Handler Posts: 89 From: Dortmund, Germany Registered: Sep 2003 posted 12-23-2003 02:59 AM                     Hmmm.. some of our films are also warped because of our low humidity but we had NEVER any problems with static! We also have CNR platters, no kinetronics cleaner or other static control equipment, just 2 conductive rollers on the projector which are grounded - belive it or not - it helps. Darren, what is the reason for flipping the print? Max  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 12-23-2003 10:51 AM                        quote: ...what is the reason for flipping the print? Film curl lends some rigidity to the film, so when there is some static cling, the print will tend to pull-in easier with one orientation vs. the other. Changing the winding orientation (soundtrack-up vs. soundtrack down) on the platter can sometimes help the print better resist pulling multiple laps.  |  IP: Logged Antonio Marcheselli Phenomenal Film Handler Posts: 1260 From: Florence, Italy Registered: Mar 2000 posted 12-23-2003 02:21 PM                        John, Thanks for your suggestions, we clean the kinetronics carefully each week. Yes, the humidity is under 30%, is very low. We're asking our AC manufacturer for a humifiers systems. About CNRs, I still think that a better ground can help preventing any static buildup. What do you think about Electrolube products? On Electrolube web you can found a grease that is conductive. I'm waiting for infos, I will try it on CNR's bearings. Max, yours is a great idea. The Cinemeccanica recommended timing is good... when you have no static problems. I will try a slower settings asap... However, why does CNR are so simple... Why Cinemeccanica does not add some "smart" to the platter? For example: the platter that doesn't accelerate immediately at full speed when the payout arm is at the maximum position... And much more... Bye A  |  IP: Logged Max Biela Film Handler Posts: 89 From: Dortmund, Germany Registered: Sep 2003 posted 12-23-2003 02:44 PM                     Hi Antonio! Yes, and the best is the Pot on the Pay out unit.. If you adjust it before the first show, the platter will turn slowly when its hot after some shows (and the arm is in the 0 RPM position..). have you downloaded the video "Show West - Cinemeccanica"? The Cinemeccanica guy said something like "When the arm gets pulled to the full-speed position, the platter will not run at full speed until the arm stays there for a little while and then it would ramp up to full speed when the platter wants it". I thought this IS a feature of the new CNR-N platters??? Max  |  IP: Logged Antonio Marcheselli Phenomenal Film Handler Posts: 1260 From: Florence, Italy Registered: Mar 2000 posted 12-23-2003 04:53 PM                        I'm used to ignore what Cinemeccanica's guys say... Kidding. I don't know, I just think that it should not be a "new" feature, it should be something present from the beginning. There is no need to be a genius to understand how important is a feature like that (and MANY others!). (just saw the video: does the platter in the video has this new feature? Don't seem to me...) Bye! A  |  IP: Logged

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