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Author Topic: Spec. For PR-1014 Gate to Trap Spacing? Pete Lawrence Expert Film Handler Posts: 192 From: Middleburg, PA Registered: Aug 1999 posted 05-27-2004 08:23 PM                     This is really two questions that are inter-related. First, is there a specific distance that the gate to trap spacing should be set to on a Simplex 35/PR-1014 with a curved gate? Spacing is adjusted by setting the Gap Adjusting Screw P-1433. I can't find anything in the books about it. Second, is it possible to get the edges of the projected image to be anything other than fuzzy. It looks terrible without masking. That's the real reason for messing with the spacing. If I close up the spacing to much the band on the sound track side will touch the aperture plate hold down spring(G-2616). I have considered shimming the aperture plate to move it forward so it's a little closer the film. Like it would be in the straight gate version. Also, I don't want to get the band tension to high. The whole aperture plate hold down leaves a lot to be desired, in my opinion. This is for a private screening room application, so I have lots of time to play.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-27-2004 09:17 PM                     Although there may be a spec for it I am not aware of one. I usually adjust it so the intermittent pressure shoes just contact and then slightly deflect when the gate is closed. I do this primarily in theatres that ahve movable masking. But in theatres that don't have movable mask then you do need to allow the gate to go into the trap a bit further to eliminate there being fuzzy projected edges of the aperature. Hint: If you set it up the forst way then the intermittent shoes last ALOT longer! Mark  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-27-2004 10:28 PM                     I dunno if there ever was an offical spec but there are practical limits. If you get the film too close to the aperture, the film the film will swell towards the light source (and aperture) and will actually contact the aperture and blister. In a screening room, with lower wattages, this shouldn't be too much of a problem. A limit you will find is that at the bottom of the trap, where the tension bands curve around, the runners will eventually contact and pinch the film. As to the intermittent shoe...on fixed tangs, we will reposition them to hit evenly and as much as needed. On new gates, the intermittent shoes are adjustable in both tilt and depth (comes this way on all new PR-1014). Since this is a screening room, you might want to consider using a straight gate or even a studio gate. Throw a 3-wing shutter in there and you will have a fine picture indeed. Steve  |  IP: Logged Paul G. Thompson The Weenie Man Posts: 4718 From: Mount Vernon WA USA Registered: Nov 2000 posted 05-28-2004 12:03 AM                     Pete, get ahold of the Simplex engineers at Strong International. In a tour of the Simplex plant that Josh and I went through a couple of years ago, I saw something on the setup of the machine that was a complete surprise from what I was expecting to see. The explanation from the engineer made complete sense - and watching the machine run a hunk of RP-40, I accepted his explanation without question. Seems to me that the new Simplex machines were set up so the intermittant sprocket shoe never contacted the sprocket - ever.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-29-2004 08:30 AM                     Paul, Are you referrring to the turreted machines (PR-2000) with the upside-down Century shoes? Or are you referring to the tried and true Simplex shoes now used only on the single lens machines (PR-1014, PR-1020, PR-1030)? If it is the single lens ones...there is a sweet spot for getting a rock stable image and I haven't found it to be non-contact. Steve  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-29-2004 08:41 AM                     Steve, The only problem with finding the sweet spot which I do agree exists and is generally in the 10 to 15 oz of film tension range as measured with a scale guage, is that as the shoes and gate parts wear the sweet spot will also disappear and move to another sweet spot requiring further tweeking to get it back, if you even can. With Estar the shoes also wear alot quicker than they used to. I still feel that the best designs are gate/trap designs which do not use shoes at all but simply use a pad roller... such as the European designs. Its just too difficult to get long term reliable steadiness from a Simplex any longer. Fortnately the poor quality of 90% of todays release prints actually cover up the Simplex's weak points. I've pretty much relinquished the Simplex to theatres that are just looking for a reliable grind machine. Its simply no longer good enough a machine for critical film use.... Because it requires too much tweeking and because there are no longer any super high quality movement parts made for them. Simplex made the last truely high quality movement parts themselves many years ago. Mark  |  IP: Logged Pete Lawrence Expert Film Handler Posts: 192 From: Middleburg, PA Registered: Aug 1999 posted 05-29-2004 04:32 PM                     Thank you all very much for the response. I had a chance to spend a little time tweaking and have a couple more questions. I should also add that I replaced the CS intermittent sprocket with a new VKF and replaced the original shoe. Both parts are new from LaVezzi. While I was at it I also replaced the bands. The gate runner looks like new. No uneven wear spots. It's interesting to note that the shoe assembly from LaVezzi looks to be chrome plated, the original wasn't. Even more interesting is it was assembled wrong at the factory. The XL manual says the shoe runner end with the larger radius should be up. They had one side up and the other side down. That little tidbit isn't in the current manual on Strong's web site. Is it still relevant? It's not in the current Simplex 35 manual. As to image stability. The checker-board image of a loop of PA-35 has fuzzy tops and bottoms for a little less than 1/4 of a square. Sides of the square are sharp. Nothing I do seems to improve it. The best setting is with the entire shoe just touching the sprocket with no film in between. If I bring the gate in closer, the stability looks worse. Side to side stability is very good. The bottom of the shoe touches the sprocket first as I close the gate. Steve mentioned he adjusts that so the top and bottom hit evenly, if I read it right. There is no adjustment on this one, do you bend the tang? Additional pressure from pressing on the top or bottom has little effect on the image. I should also mention this machine is the single lens version, and has a three blade shutter. Any travel ghost can be eliminated at both the top and bottom, but without much to spare. Lamp is an ORC M-1000. Intermittent runs quiet with no play in the locked positions, that I can detect. Film path alignment looks good and was set with LaVezzi's gauge and steel film. Vintage is from the era when National Theater Supply / National Screen Service made them. Sound head is a RCA 9030.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-29-2004 05:56 PM                     Pete, You are correct on the proper positioning of the shoes. But be sure that you also have the correct spacers in there between the outer shoe and the inner shoe so you have the correct amount of clearance for the wider VKF tooth. If you don't you might actually scrape the sides off of the teeth. Seen that many times from other techs that just didn't know about the spacer difference or that perhaps didn't care to do it right. Another way to drastically improve lateral steadiness is to install Posi-Trol sprockets in all three positions in the head. These sprockets work wonders!! The steadiness you mentioned is good but many other machines do alot better day in and day out. A typical good running SA can do half that amount of movement and I always used Centurys for dailies work because of the high consistancy in picture steadiness. Also, some European machines can put up a picture with no visible movement... even steadier than DLP! You will find an occasional X-L that can also do that but they are rare these days. Its mainly attributable to the differences in tolerances that the U.S. and European parts makers work to. The well made X-L movements had cams that were assembled fomr three parts and the radius was actually bolted to the shaft by three allen head screws. Those are the best X-L movements. Mark  |  IP: Logged Josh Jones Redhat Posts: 1207 From: Plano, TX Registered: Apr 2000 posted 05-30-2004 06:04 PM                        while we're on the topic, I've always been fond of the 50's-60's era XL's. Nice and quiet, steady. Is this just my perception, or are they really that good? I know where a 50's era XL with like 300 hours is hiding Josh  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-30-2004 09:23 PM                     Josh, By gosh....The earlier X-L castings are pure crap....very inconsistent in thickness and EXTREMELY porus. They leak like a seive! I've actually seen quite a few main castings with a front wall thickness of less than 1/8th inch! The General Precision made X-L's to todays castings are of excellent quality with much thicker and less porus alumnium. With earlier X-L's the intermittents and associated parts had much better fit and finish and the shockproof gearing was excellent... made the machine run almost noiseless and vibration free. On the other hand todays intermittents and related parts are not made as well or to as tight of tolerances as the made by Simplex's movements were. Later machines can run quiet after an extended break in period but they are no where near as quiet as the early versions. Those shockproof gears also got rid of alot of vibration that is now inherently built into every X-L. Mark  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 05-30-2004 09:40 PM                     That's why there is the PK60.  |  IP: Logged Josh Jones Redhat Posts: 1207 From: Plano, TX Registered: Apr 2000 posted 05-31-2004 03:00 PM                        Mark, have you had any luck powdercoating the castings to stop the leaks? Josh  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-31-2004 03:22 PM                     Josh, Yes, Powdercoating works wonders on them. Stops about 95% of the oil leaks. But finding someone thats good at powdercoating them and de-greasing them is sometimes difficult. We have been lucky with that out here as there are everal large powdercoating facilities that really know how to clean thees castings properly. We were using another smaller powdercoating facility but they had constant problems with oil bleedout and such so we switched over to these new guys and they have been doing consistant, literally flawlss work. Cost is about 120.00 per set of X-L castings including the manual paint stripping of the main casting and other castings with precision machined surfaces... this is definately the better way to go with these pieces. Many of the castings can be bead blasted though as they have no machined precision surfaces. Mark  |  IP: Logged Pete Lawrence Expert Film Handler Posts: 192 From: Middleburg, PA Registered: Aug 1999 posted 06-04-2004 09:25 PM                     quote: Brad Miller That's why there is the PK60. If only... Let's see, re-mortage the house, sell the kids, make the second million in the stock market, well you get the idea. I'm still looking for Steve's sweet spot on setting the gate. It still seems to flutter and cause fuzzy tops and bottoms on the checkerboard of PA-35. Any suggestions?  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-05-2004 08:49 AM                     We've heard of several PK-60D owners leaving the gate open and melting them down when they inadvertantly left the xenon turned on...... a distant cousin to Three Mile Island I guess.... so... Install a DP-70 instead !! Then you can do critical viewing in all formats.... These machines simply can not add any machine induced vibration like some of the lighter weight equipment does... Mark  |  IP: Logged

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