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Author Topic: How Heavy a Load for an RCA1040 Harry Robinson Expert Film Handler Posts: 155 From: Franklin Tennessee Registered: Dec 1999 posted 04-23-2004 02:24 PM                     Some of the prints I have been showing lately run 10-12 reels. Using 3 2000' reels per 24" 8000' reel requires three breaks during the show. I wish I could afford a platter for my screening room, but lacking that I need to know how much film the old RCA 1040 sound head can pull. The last time I tried to pull 8000' the take up reel belt started slipping and I had to shut down before I had film all over the floor. The belt had become loose over the last three years, and it had a sheen of oil from the Super Simplex and the 1040 leaking. My question is: If I shorten the belt is there a danger it will pull the film with too much force and damage the sprockets as they come through the 1040? How tight should a take up belt be? Any comments from you guys will be welcome.  |  IP: Logged Bob Koch Expert Film Handler Posts: 183 From: williams ca Registered: Nov 2001 posted 04-23-2004 10:21 PM                     If you have a true MI 1040 reproducer it has no flywheel and the terrible jerky starts were a real problem even when I was a boy. The stock resistor in the starting winding never helped and I resorted to many unorthodox and bad fixes to dampen the start. One was to put an electric heater element or a 2 ohm resistor in 1 side of the line to the motor. It worked, but really reduced the torque; if you had an intermittent with a high spot it might hang up. You don`t mention what kind of a takeup you have but if its a conventional friction disc type the belt wants to be tight and drive the outer pulley at a constant speed thruout the reel with the friction material supplying the variance in speed. I can appreciate your problem in that this existed with only 2000ft reels. Make sure your 26241 hb sprockets are in good shape and not "hooked". Bear in mind,this soundhead was designed in 1935 when the industry was still using 1000 ft reels and just going to 2k. They then brought out the MI 1050 with a flywheel which took care of the problem.  |  IP: Logged Jack Ondracek Film God Posts: 2348 From: Port Orchard, WA, USA Registered: Oct 2002 posted 04-24-2004 12:55 AM                        The problem we had with the old friction-type takeups (also the Cinemeccanica towers) was more a matter of getting the tension right than whether the projector could handle the load. The simple takeups with the leather pads were the worst.... all kinds of pull on the film at the head of the reel... much less when the reel was full... especially when using 6K reels. There was a takeup that applied more power, based on the weight of the filling reel (I don't remember who made it, though). The one thing that the Ballantyne VIPs seemed to do OK was handle large reels... what were they, 12,000 ft or somax? The absolute best reel-reel systems I ever used though (hope I don't find myself in the "you suck" thread for this) were the Ballantyne Sword and Double-MUT transports. Find yourself one of these & you can run the whole show on one reel & not torque the film (or your soundhead) at all.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 04-24-2004 08:45 AM                     Always had good luck with the double muts from Eprad the swords the control system was a bit different  |  IP: Logged Harry Robinson Expert Film Handler Posts: 155 From: Franklin Tennessee Registered: Dec 1999 posted 04-24-2004 12:03 PM                     Well, I tightend the belt and adjusted the tension spring on the take up arm. I ran an 8000' reel, and it performed perfectly. Because I came into this thing from the hobbyist's perspective I occasionally get a little stage fright at trying to make adjustments. I've screwed up my equipment a couple of times, but each time I learn something.  |  IP: Logged Lindsay Morris Expert Film Handler Posts: 233 From: Darlington, WA, Australia Registered: Sep 2002 posted 04-25-2004 03:41 AM                     Harry, Many of the Drive Ins we used to have in Perth West Australia back in the late 60's went to 6000 foot spools still running carbons getting just about an hour out of each feed setting and many were RCA 1040 or 1050 heads. Never any problems getting going but many did prefer the floating hub spools. You seem to have found your problem Ok but belt tension is critical as is the clutch tension and the best way to set that is as for when you ran a 2000 footer setup was to put a FULL reel on the the takeup and start the machine and observe how that full spool got away. If it raced away the tension was too much on the clutch, if it took ages to get rolling it was too light... some where in between those 2 points is the optimum. So it became a matter of trial and error to set the correct tension. Remember that the setting then is for a 6000 footer, put on a 2000 footer and you will most likely have far too much tension and be pulling the hell out of the sprocket holes which you can normally hear as a rasping buzzing noise as the film is taken up. This is easily checked by GENTLY retarding the spool by using your hand carefully on the rim and if the noise abates you have too much tension. Equally by watching the takeup throughout it's cycle from empty to full you can detect under tensioned drives as the film will come away from the hold back sprocket in a curving sloppy looking loop rather than nice and straight down to the spool. It also might be tending to dance about or snatch which is not good for film and again your ears will tell you it is doing just that. Keep the takeup shaft and pulley bearings well lubricated as they are only simple plain shafts as a rule and they DO work rather hard when on 6000 foot spool duty. There are often 2 lube holes to attend to, one in the housing for the actual shaft thru to the spool box side and another in the pulley itself as it spins on a shoulder to allow the clutch action to take place. Many operators forget the one on the pulley (as you cannot always see it) and as it gets all gunky wonder why their takeup is all over the place... but a few drops of oil fixes it easily. Keep the clutch pads relatively free of oil.. just the slightest trace is needed to keep those spinning discs working nice and smooth and you will have a nice full spool firmly wound and no sprocket damage. Lindsay  |  IP: Logged Josh Jones Redhat Posts: 1207 From: Plano, TX Registered: Apr 2000 posted 04-25-2004 07:16 PM                        of course, with the setup Harry speaks of, the takeup arm will be self oiling Supers drip a little bit ya know! Josh  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 04-25-2004 07:36 PM                        quote: of course, with the setup Harry speaks of, the takeup arm will be self oiling Supers drip a little bit ya know! That's why he probably has either a stack of old newspapers or a tray filled with cat litter on the floor under the projector. The obvious solution here is to reinforce the house foundation and upgrade to a pair of DP-70s (Brad's favorite machines)!  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 04-25-2004 10:13 PM                        quote: Scott Norwood That's why he probably has either a stack of old newspapers or a tray filled with cat litter on the floor under the projector. Another good oil catcher is an opened (clean) disposable diaper, or one of those waterproof absorbent pads used for people with incontinence.  |  IP: Logged Christopher Seo Jedi Master Film Handler Posts: 530 From: Los Angeles, CA Registered: Jun 99 posted 04-26-2004 08:49 AM                     I've taken to stuffing paper towels into the drive side of my 1040s, between the gear compartment and main casting, and this has drastically reduced the need to clean oil off the take-up belt, floor, etc. I also run 6000' reels on Kelmar arms with these soundheads, and am wondering if anyone has quantifiable real-world recommendations for take-up tension. I.e., how many newtons of tension (as measured at the hub with a spring gauge) will produce a satisfactorily tight wind with 6000' of film? I suppose a 'satisfactory' wind could be defined as a wind in which the outer convolutions of film are wound tightly enough that they will not cinch when rewound with enough tension to ensure that they will also not cinch while being pulled off the hub of the feed reel. For a basic take-up clutch assembly, the SMPTE RP-106 spec of 4.4 N maximum is clearly far too little. If the hub were set with that tension, the outside of a 6000' roll would be mushy soft, probably to the point of sagging below the reel edge. I have found that hub tension somewhere around 15 N produces a tight wind at the edge, and is far below the SMPTE 'rupture limit' of 66.7 N, but at the cost of high tension on the first 500-1000' of film and possible premature wear on the holdback sprocket.  |  IP: Logged Josh Jones Redhat Posts: 1207 From: Plano, TX Registered: Apr 2000 posted 04-26-2004 04:01 PM                        which may be fine as long as it is not contributing to, or causing film damage. sprockets are cheap, prints are not. Josh  |  IP: Logged Harry Robinson Expert Film Handler Posts: 155 From: Franklin Tennessee Registered: Dec 1999 posted 04-29-2004 12:22 PM                     I've been using a 9X11 baking pan to catch the oil. I couldn't use cat litter because I'm afraid the cats might start using it, then there's smell and oil everywhere. But the diaper idea has merit. I'll try that this week. About the Super: Sure it leaks, but the picture is rock steady and the prints are showing no wear (Of course I'm using Film Guard on every Pass).  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 04-29-2004 01:39 PM                        For small areas, "feminine hygiene" products (sanitary napkins and tampons) can work well as oil absorbers too.  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 04-29-2004 02:38 PM                     I used to use an E-Z Foil baking pan. They're cheap and disposable. When they get all cruddy you can just wad them up and throw them away. A while back I found a lid from a round film tin. There is no bottom so it's useless to keep film in. I just put a couple of sheets of newspaper in the bottom of it. When it gets cruddy I simply replace the paper and/or wash out the tin with soap and hot water. Besides, it is a projection booth. It's nice to keep everything with a film "theme".  |  IP: Logged Paul G. Thompson The Weenie Man Posts: 4718 From: Mount Vernon WA USA Registered: Nov 2000 posted 04-30-2004 02:12 AM                     Stuff or tape a Kotex® under the sound head. They are very effective in absorbing sound head and projector head oil.  |  IP: Logged

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