my profile | my password | search | faq & rules | forum home

» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Cinemeccanica Victoria 8 electric douser

Author Topic: Cinemeccanica Victoria 8 electric douser Mike Rendall Film Handler Posts: 78 From: Southampton, Hampshire, UK Registered: Nov 2002 posted 12-09-2002 08:40 AM                     The electric douser (changeover) on our vic 8 seems to be very sticky, i.e. you can push the button and it can take up to 3 seconds to fully open! Is this a problem with Vic8's since many of them have dodgy dousers. I get the feeling that the electric douser on these machines was an afterthought. The vic 5 on the other hand seems to sense that you want to open the douser, just walk near it and you get the sccchlannng as it scrapes its way open.  |  IP: Logged Darren Briggs Master Film Handler Posts: 371 From: York, UK Registered: Dec 2001 posted 12-09-2002 01:36 PM                        The douser should be free to move by hand up and down, if it aint it's obviously touching something it shouldn't be or the solenoid isn't free to move. Otherwise it should be very fast at opening or closing. To see if its the solenoid or the douser itself which is causing the fault, take off the small screw that fixes the douser solenoid to the douser shutter. Then see which is hard to move. But thinking about it is it the type of electonice douser on the top of the shutter case, or the type on the push button? Im sure Ken Mcfall can help on this subject more, as he run's four Vic 8's and knows then like the back of his hand. Darren  |  IP: Logged Richard Fowler Film God Posts: 2392 From: Ft. Lauderdale, FL, USA Registered: Jun 2001 posted 12-09-2002 03:22 PM                     Cinemeccanica has had several versions of changeover / fire shutter to the V-8. The bearing which the douser rotates is a common problem as the unit wears and the ease of travel or squareness to the travel slot become worse.  |  IP: Logged Ken McFall Jedi Master Film Handler Posts: 615 From: Haringey, London. Registered: Apr 2001 posted 12-10-2002 05:33 PM                     Well thanks for that Darren. The Vic 8 dowsers are a in general very reliable but as in everything they do need to be checked over once in a while. As Darren has already explained uncouple the dowser and the coil and with the projector running, to lower the ruptur device, check if the dowser will open easily. Then lift up the rupture device and see if the dowser drops quickly. You should not be able to feel any real resistance or hear any scraping sounds... your Vic 5 needs checking as well by the sound of it. If all of that checks out ok then check the coil for free movment. Couple them back togeather and try again. It could just be a slight alignment problem. If not you will need to remove the shutter casing as the dowser may be buckled due to heat or the whole thing has just got dirty over the years. None of it is complicated engineering and once apart its easy to see how it all works. HOWEVER... removeing the shutter casing is quite a big job. The lamphouse has to be pulled back... some 6-8 inches at least. The Change over shutter coil wiring has to be disconnected and then remove the screw that connects the actuator arm to the shutter linkage, on the later type actuator, then remove the assembly. On the older type you can hang the assembly without undoing the bowden cable. There is no need to disconnect the lacing lamp unless you are removing the gate assembly at the same time. It's held in place by two screws/allen bolts and again quite easy to clean etc. There may be more wires depending on the installation but normally its three wires for the changover shutter and two for the lacing lamp! Early installs had connections to micro switches inside the change over shutter assembly. These are no longer fitted in newer installs. Note the locations of these wires, the changover shutter will be 220v so be careful..... Power off at all times! Now undo the four screws/allen bolts that hold the shutter housing in place and pulling out from the bottom first then upwards life the assembly up and off. The rupture device needs to be nursed slightly. On the bench you will see that the actual shutter blade runs in a guide slot so check that its not distorted and allows the blade to move freely. If not you may have to bend the small bar that runs in the guide slot. The rest is then giving the whole thing a really good clean. You won't be able to dismantle it completly but you should be able to get to everything you need to. Scratching on the shutter blade are a give away that the blade is rubbing against something so again check it out. The main thing that I've seen is distortion of the shutter blade due to over heating when the lamphouse dowser has been left open and the lamp has been burning directly onto the blade. A bit of common sense and time will sort it all out. As this is a once every few yaers job its worth taking advantage and cleaning everything. These instructions are accurate but depending on the type of changeover assembly you have, bowden cable with the thin tube directing the cable into the shutter assembly or the flat spring metal actuator, you will need to determin if you can completely remove the change over coils or not. Undoing the bowden cable is not difficult but putting it back together is fiddly and needs to be setup correctly. If you can avoid undoing it its better. You have to be avoid the shutter being pulled too far up against its limit or pushing too far down against its limit. Both will cause the bowden cable to wear very quickly and break. However, if you are going to do this yourself I always suggest doing it after the show last thing so you have plenty of time. I can do it all in about 30 min but I would allow a couple of hours at least if you've never done it before. While its all apart give everything a good clean generally but don't force the flicker blade, use the motor inching handle to turn it. ================== Quick note: If you ever have a shutter cable or spring actuator break on you, you can open the change over shutter by passing a length of stiff wire with a hook bent into the end. Insert it into the top of the shutter housing where the cable or actuator enters. The idea is to hook the shutter blade and then pull it up and tie it open. Got my staff out of trouble a couple of times. ================== Putting it all back together is quite simple just be careful of the rupture device and the flicker blade. There should be locating pins so it will all go back in place correctly. If you have to force anything then DONT! go back a step and try again. There are no special tools required just care and cleaning.... oh and some common sense. One final point.... before you start run the projector and put white light on the screen. Make sure your lamp is correctly lined up. When you put it all back it will help you in positioning the lamphouse correctly. Let's not get into lining up lamphouses as that is a subject all on its own!! Doing this first should allow you to get back to at least the same position you were it before you started. Contact me if you need any further help.  |  IP: Logged Mike Rendall Film Handler Posts: 78 From: Southampton, Hampshire, UK Registered: Nov 2002 posted 12-11-2002 04:56 AM                     Thanks Ken for your exceptionally detailed instructions. I have had a look and I think I have sourced the main problem. The solenoid that pulls down the bent bit of wire that then moves the douser arm is fine, the problem lies in the fact that with the dowser shut the solenoid is at the end of its travel and hence does not have large enough contact area with the coils for a sufficient force to be generated. If you adjust the end stop of the dowser you can make it work perfectly. The problem with that is that the dowser then does not fully shut and so you get a large amount of light spill on the screen (I have had to resort to using the fire dowser only and leave the electric one permanently open). Unfortunately, there isn't a compromise position whereby you have sufficient force to open the dowser and not let any light through. I have looked at the position of the solenoid with the thought of moving it but as it doesn't have any extra screw holes in it, or tracks that you can move the position of it. The only other alternative is to check that the actual metal blocking the light is large enough. This is a new install so the engineer is coming to take a look at it when he is next around but I was wondering if there was a quick fix. You were right about mains voltage around there, I accidentally touched one of the contacts and got a shock (I mistakenly thought everything would be low voltage 12V - You live an learn.) I orignally thought that there wasn't enough current getting to the solenoid due to a dodgy contact (not unusual in these machines). Thanks again for all the help, I will post when the engineer has sorted it out. (pictures are on Union Films web page) Mike  |  IP: Logged Ken McFall Jedi Master Film Handler Posts: 615 From: Haringey, London. Registered: Apr 2001 posted 12-12-2002 09:46 AM                     You're welcome for the info Mike... Didn't realise that Nigel Shaw did your install.... Now he is a guy who knows the Vic projectors like the back of his hand. I'm an amateur compared to him and he's a nice guy as well. Now if only all engineers were as pleasant to work with life would be much easier all round. I'll expect to have my post returned to me marked out of 10 if he reads it Give him my regards.  |  IP: Logged Mike Rendall Film Handler Posts: 78 From: Southampton, Hampshire, UK Registered: Nov 2002 posted 12-12-2002 10:36 AM                     You're right, we have only ever had Nigel do all the stuff for us, he lives round the corner (relatively speaking) and he tries to pop in when he has done jobs up in london as we are on the way home. If you ever want to wind him up - ask him if he has got a soldering iron permit... he he he.. I don't think he reads this site but he is now online and regularly send me emails at the moment. Mike  |  IP: Logged Ken McFall Jedi Master Film Handler Posts: 615 From: Haringey, London. Registered: Apr 2001 posted 12-13-2002 08:02 PM                     I chatted with NIgel the other day... seems he's tried to register a couple of times and had a problem...... We need guys like him on here so if you can bring any pressure on him to try again, do so. If he has a problem Brad will sort it out I'm sure.  |  IP: Logged

All times are Central (GMT -6:00)

Printer-friendly view of this topic

Hop To: Select a Forum: Category: Operations -------------------- Digital Cinema Forum Film Handlers' Forum Large Format Forum Ground Level Feature Info, Trailer Attachments & REAL Credit Offsets Category: Community -------------------- Film-Yak Film Handlers' Movie Reviews The Afterlife Bob Maar's Joke-A-Thon Category: Classified -------------------- Equipment and Supplies Wanted/For Sale Help Wanted/Seeking Employment Category: System -------------------- Software Beta Testing Forum

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.