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Author Topic: Aperature plate quandary Christopher Meredith Expert Film Handler Posts: 126 From: Jackson, MS, USA Registered: Apr 2006 posted 05-24-2006 07:46 PM                        Our theater uses Strong equipment and most of it is older. The lens turrets, lens switchers, and aperature plates used to be motorized but flaky automation has caused us to remove all but a few motors from these things. Also, the UV from the Xenon bulbs has fried most of the motors and wiring for the aperature plates. I work for REG and they don't want to put money into parts that will just get fried again. Also, severl motors have been removed, which makes the aperature plates slide back and forth freely. Even the vibration of the projector will cause these to shift very slightly which makes a big difference by the time the light hits the screen. To top it off, I am the only projectionist at my location who even frames up the movies when threading, let alone ensures that the picture is not overspraying. So here's my two-part question: 1) If we want to replace the motors and wiring, is there a shield of some sort we can use to protect the motor and wiring? 2) If we elect to remove all these motors (as some already have been), is there any product or method used to manually move the aperature plates but then have them lock or click into position so they don't move? Thanks!  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 05-24-2006 11:25 PM                     quote: Christopher Meredith So here's my two-part question: 1) If we want to replace the motors and wiring, is there a shield of some sort we can use to protect the motor and wiring? 2) If we elect to remove all these motors (as some already have been), is there any product or method used to manually move the aperature plates but then have them lock or click into position so they don't move? I work with a small company that has practically the same booth setups: Simplex PR-1050's that HAD the automatic turrets - the turrets that swung out between len changes and the sliding aperture plate that was also driven by a small turret motor on that mount plate next to the trap assembly. This small company decided to remove ALL of that motorized stuff since the decision was to turn the booths into a KISS - (Keep It Simple, Stupid) - operation. They did like anything complicated to the 'booth clowns' that worked in these theatres, due to no proper training was available. My automations are the STRONG CPA-10 units, in which I really had no problems with - and this automation did do all of the neat tricks that it can be programmed to do With the motors and hardware all removed, I also had the problem of free-sliding aperture plates. I took the plates out and put a slight warp, in the area of both aperture openings so that the plates would lock into place per each lens format by being snug in the trap opening area. If you can be lucky to keep the motors on in their place, esp. the aperture motor, you can rework the wiring over and out of the way of the xenon light. Sad, but some companies can see that putting their money into new theatres are more of in the area of important priorites than into older locations. Hate to say, that if that's the case with your theatre where no money is spent there and it's older, it could be ready to be shoved on the auction block down the road..better be aware of this... good luck..-monte  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 05-25-2006 04:36 AM                     I've removed the auto aperture changeover motor from Century gates before and "converted" them into single aperture machines. Worked great, and you just spin the lens turret by hand to flip lenses.  |  IP: Logged Steve Scott Phenomenal Film Handler Posts: 1300 From: Minneapolis, MN Registered: Sep 2000 posted 05-25-2006 12:27 PM                     Our Century SA has a UA auto lens changer mounted to the front of the head, the clunky kind that just swings the appropriate adapter in front of a prime lens. While the equipment is still mounted on the head, the old gate with the small outboard motor to move the apeture plate has since been replaced with a traditional SA gate. That came with a new flat plate, but our scope plate is just an amputated version of the UA dual plate, so it also has had issues with staying flush with the guides in the new gate. Lately it's become tighter, but before we had a scrap square of another plate wedged between the new gate & plate to steady it. Although steady is realtive for this particular SA because it's a wonderful Century-to-ORC transition model You may want to consider the cost of conversion to a single lens mount. You ought to have far fewer apeture positioning problems that way. My experience with the newer Centuries reflects what Brad said, the manual turrets are enough to adjust as-is and as long as you're not crazy about automating everything, excellent units.  |  IP: Logged Tim Reed Better Projection Pays Posts: 5246 From: Northampton, PA Registered: Sep 1999 posted 05-26-2006 04:47 AM                       quote: Topic: Aperature plate quandary Oooooh! Sorry to be a snit right off the bat, but this is one of my pet peeves. It's APERTURE, not aperAture.  |  IP: Logged Christopher Meredith Expert Film Handler Posts: 126 From: Jackson, MS, USA Registered: Apr 2006 posted 08-07-2006 04:42 PM                        Just wanted to share with everyone how I solved the problem. I fashioned a locking mechanism for the aperture plates which is simple yet very effective. To do this, all you need is what Home Depot calls a wing screw (I believe the size was 4.2) and a 10mm washer. The wing screw needs to be pretty short. In my case, Home Depot didn't have enough short ones so I bought long ones and dremeled them off. So to do it, you just remove the screw that keeps the aperture plate retained, re-use the small washer that's there already, and put the small washer then the 10mm washer on the wing screw then tighten it down. To switch formats, all you have to do is loosen the screw slightly, slide the aperture plate over, then retighten. It won't budge!  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 08-07-2006 05:24 PM                        Is that a flat gate? Louis  |  IP: Logged Christopher Meredith Expert Film Handler Posts: 126 From: Jackson, MS, USA Registered: Apr 2006 posted 08-07-2006 05:31 PM                        Yes it is.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 08-07-2006 10:58 PM                     Wonder if you should just remove all of those aperture changing motors for I can see the motor actually causing you probs with the aperture wanting to swing back to the "flat" positon. We took ours out completely to where there is nothing in the slot for the aperture...and we've had no probs of aperture drifting..but on some that did want to drift, I just put a slight bow in the plate to make it snug in the slot.  |  IP: Logged Adam Martin I'm not even gonna point out the irony. Posts: 3686 From: Dallas, TX Registered: Nov 2000 posted 08-07-2006 11:21 PM                     Why is there a Pro-35 gate in that Simplex?  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 08-08-2006 12:27 AM                     (If you're referring that plate attached to the outboard side of the trap....) that plate is an after idea from Simplex which is bolted on to the side of that trap by two long allen screws, plus with the adapted band adjuster - so the aperture motor can be mounted and used to swing the plate back and forth between formats. It wasn't until middle or late 89 that Simplex FINALLY made a one piece trap (and usually curved) that would include the aperture change motor. I bet that his Simplex 1050 machines were built in either 87 or 88 and being the flat trap variety - all he has to do is look at the manufacture date on the lower part of the shutter cover where the model and serial number is at.. -Monte  |  IP: Logged Christopher Meredith Expert Film Handler Posts: 126 From: Jackson, MS, USA Registered: Apr 2006 posted 08-08-2006 08:50 AM                        Yeah, most of our machines were made in '88. I am in the process of removing the motors (as well as the motors on the lens turrets themselves). It helps with the aperture plate drift but even the ones with no motor will shift by just a millimeter sometimes, which causes a slight shadow on one edge or the other. Tried bending them as per your suggestion, but it was hit or miss. This is my permanent fix! I like my flat gates, BTW. We have 4 machines with 1060's (and one 2020) which have the curved gates and I can't get the picture as steady on them as I can on the flat gated ones.  |  IP: Logged Charles Greenlee Jedi Master Film Handler Posts: 801 From: Savannah, Ga, U.S. Registered: Jun 2006 posted 08-08-2006 09:37 AM                        Our machines date back to the early 80's, they all currently have curved trap and gates, except #2 which has the flat one. I suspect they had upgraded at one point, and #2's gate went bas later and they had to go back to the flat spare. That said, I've had no trouble with the gate, except it is noisier due to the thick, spring loaded, bands. There's not even any noticible breathing on screen, of course we've only got 2kw bulbs in our houses.  |  IP: Logged

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