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Author Topic: Anyone have a RCA soundhead thread pattern? Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 12-03-2004 06:52 PM                        I've run lots of film on those RCA soundheads (and SH-1000s and 5-stars) and I've never seen "track marks" like the ones pictured above. I don't doubt that the "dirt embedder" roller is a bad idea, but I honestly can't say that I've seen any film damage that was directly attributable to it, as long as the rubber roller itself is clean and not caked in years of dirt from sitting idle. As for Century soundheads, what's so wrong with them? They don't have any parts that touch the image area of the film, nor do they have the flaws of the Cinemeccanica V5 or Kinoton designs. (I'm not commenting on sound quality here...just potential for film damage and convenience to the operator.)  |  IP: Logged Tim Reed Better Projection Pays Posts: 5246 From: Northampton, PA Registered: Sep 1999 posted 12-03-2004 07:07 PM                       That's right, Scott. And let's remember, guys, these were originally felt rollers. The track marks are from the rubberized "improved" version. A Century on an RCA was a popular, and fair combination... especially from the reproducer's standpoint. It was a lot easier than driving a Brenkert on top! Justin, I could've sworn a 1/4-20 screw was right for that cover.  |  IP: Logged Ian Joseph Parfrey Film Handler Posts: 56 From: Bollier Queensland Australia Registered: Sep 2004 posted 12-03-2004 09:14 PM                     My main gripe with the Century S/heads, the TR4 in particular, is the propensity to wow due to the one sprocket being used for hold back and take-up at the one time. My beloved RCA's always used two sprockets in the place of Century's one, one after the sound drum for hold back and one for takeup. This seemed to prevent any fluctuation in linear speed due to warped spools or eccentric platter rings. And it's harder to break down on the fly because film piles in the soundhead casting I have never had an RCA wow on me under any circumstance and just reckon that they are the best bar none. Solid, Dependable, Gentle on film, Reliable. Isn't that what all gear should be? How can the Christie "Ultamittant" get an oscar when those pieces of shit don't deserve it and the RCA gear doesn't has got me stuffed!  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 12-03-2004 10:42 PM                     That extra sprocket doesn't have anything to do with wow. You probably ran some Centurys with bad bearings. Also, RCA heads are NOT "gentle on film". Geez, do you really not understand?  |  IP: Logged Will Kutler Phenomenal Film Handler Posts: 1506 From: Tucson, AZ, USA Registered: Feb 2001 posted 12-04-2004 02:10 AM                     Dan, those machines look filthy! 2 suggestions for you: What kind of shape are the sound-drum casting isolators/insulators in? Have your replaced the sound drum bearings with sealed type so that you do not have to fill the sound drum casting up with oil? There are some excellent gasket material out today that will help prevent gear-box leakage. Another thing, is the gear-box cover warped? If it is, a machine shop can straighten that out, but you may also need to make up the difference with gasket material thickness...such as is done on auto-engines (different thickness of head gasket). Also, make sure that you correctly tighten the gear box down in a correct criss-cross pattern, and dont over torque the screws! And don't over fill them with oil! Properly cleaned and maintained, those ole RCA's should run like a dream. And if you are so inclined, a motor shop can clean up the motors and replace the greaseable bearings with sealed ones! Cheers K.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 12-04-2004 02:32 AM                     Will, I've been to Danny's theater and the film path IS spotless. You are making your comments based upon the cosmetic issues of many decade's time. Besides, why in the world would someone want to take a lousy soundhead and restore it when there are BETTER soundheads, like the Century, available on the used market for much less than that boat anchor could be "prettied up" for?  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 12-04-2004 08:38 AM                     quote: RCA's with the double loose loop and mag-coupled flywheel have the lowest wow/flutter ratio in existance, I'm not sure what planet this guy is from but he's wrong on both statements above.... its got to be that I-30 stuff! The flywheels on RCA cinema soundheads are not magnetically coupled they are oil coupled... if the oil has not leaked out over the years which many do. And secondly the sound reproducer with the lowest flutter specs that I have actually measured is the Kalee 21 @ .07-.09%. The RCA and Simplex SH-1000 flutter specs are typically the same at .15-.25%... depending on what projector head is mounted on them, Brenkert heads on an RCA increase that spec to a bit over .3% and thats why RCA came out with the 9050 and the projector drive arrangement off the lower sound reproducer sprocket shaft. I have never measured a 9050. The only magnetically coupled cinema soundhead stabilizers I am aware of are the Cinemecanica V-10(not all of them were), and the Century R-2. There may have been other European machines with that feature but definately NOT RCA. Many R-2 flywheels have also become somewhat de-magnetized over the years!! Ian, when was the last time you ACTUALLY MEASURED W&F of any sound reproducer? I don't think you ever have.... You also need to cut open an RCA flywheel and learn how the thing works . Weather the RCA cameras ever had magnetic coupling is also debatable and may depend on when the camera was actually manufactured. The RCA cameras I've seen fo not and use the idential oil damped flywheel. I have books on many of the various sound cameras if you'd like me to look it up and see. quote: How can the Christie "Ultamittant" get an oscar when those pieces of shit don't deserve it and the RCA gear doesn't has got me stuffed! Why shouldn't it deserve a technical oscar? It is the first and only totally sealed movement that doesn't ever leak in 99% of its installations. Of the many thousands sold very few movements actually ever fail thanks to its special synthetic oil. The Christie projector when properly maintained on just a yearly basis is not at all bad and the latest version with the new belt drive scheme which has eliminated the double sided timming belt is a very efficient mechanism indeed. Its soundhead W&F specs are actually far better than the RCA or Simplex. Danny, Those RCA's interiors speak for themselves of the years of service they've given!! They have a nice patina to them. Century reproducers are ok and have fewer moving parts, expect the stabilizer performance to give you W&F specs somewhere around .25%. Just be sure that any Century that gets installed has all ball bearing dancer arm rollers and that the output roller at the bottom is also ball bearing. The R series reproducers that have bushings on the sprocket shaft actually have a tad bit better W&F spec than the later ball bearing variety do... but they need oiling once a month. Justin, Try Wolk for that thumbscrew, or run a 1/4-20 tap in both of those dang holes and change the thread. There is enough metal there to do it because the 1/4-20 threads are taller than the fine thread. I've done that on several occasions and it works juat fine, just use a two flute tap and tapping fluid when you do and back the tap back out to clean off the chihps about every turn or two of the tap. The latter two might cost more to buy that the correct thumbscrew though. The original is an odd thread for what ever reason..... Probably the only really dumb aspect of the Century head. Mark @ CLACO  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 12-04-2004 09:07 AM                    Not gentle for any reasons besides the roller? With both RCA and Simplex going to a fair amount of trouble to have two sprockets to divide functions I think it's safe to presume that it does provide a certain amount of isolation from takeup anomolies. With a platter the tree or arm should keep things fairly smooth but with reels if a funky reel is causing some glitches in take up tension every turn it's hard to see how that wouldn't have at least some effect on smoothness of film motion by the scanning drum.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 12-04-2004 09:17 AM                     Steve, You're absolutely correct. Bad reels, a bad or improperly adjusted or maintained take up can actually be heard and quite easily. Ditto for the 5 star and the el crapo 35/70 X-L free wheeling penthouse!! During a screening of L.O.A. at McClurg court that wow was very definately audible near the end of a reel on just one projector when it was spinning its fastest. Mark @ CLACO  |  IP: Logged Will Kutler Phenomenal Film Handler Posts: 1506 From: Tucson, AZ, USA Registered: Feb 2001 posted 12-04-2004 01:46 PM                     "Restoring" that RCA is not really that expensive or time consuming. Actually, some bleach, household cleanser or paint cleaner will easily remove all those stains! On the other hand, dissassembly/reassembly of the unit (outside of projector alignment) is not really that time consuming. Take all the castings to the powder coater and either have them powder coated or epoxy painted. Now, some powder coaters may have a minimum charge regardless of the job. Or some might due a quality job at next to no cost...if a "standard color" like black or machine grey is used, and your job can be ganged to other orders. For example, I had a non-cinema related project I was working on. One powder coater had a min $100.00 charge, period. Another quality powder coater was only going to charge me $15.00, as the standard color was to be ganged with other simialr color orders. The rubber isolators/insulators and pad roller costs are peanuts. THe expensive part is the slit lens (if you need to replace it due to oil penetration), the bearings and sprockets if need be. As for projector motors, they basically have the same specs as household motors that yopu can purchase at Ace Hardware, Home Depot or the like. And these motors run $50.00 or so, whereas projector motors are ungodly expensive! Why are projector motors so expensive? We have had this discussion in other threads, but the projector manufacturers attempted to bullywink customers by putting "special" specs on the data plates, while at the same time incorporating specially tapered winding shafts that connect to the soundhead. Notice that these new store bought motors will also fit in the origonal motor cradles. In fact, the same cradles are avaiable at the local home-improvement stores, they are just stamped from a lighter gage metal. Who knows, maybe with some ingenuity, new store bought motors might be adaptable to those older Simplex/RCA soundheads? Cheers K  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 12-04-2004 03:29 PM                     Will, Lemon scented oven cleaner works the fastest and is the safest on yourself. Use of bleach or other chemicals might land you in the emergency room. Als, no one is using slit lenses any more...... Store bought motors..... might on xome Centurys but then there is the flywheel thing to deal with. Mark  |  IP: Logged Tim Reed Better Projection Pays Posts: 5246 From: Northampton, PA Registered: Sep 1999 posted 12-04-2004 04:55 PM                       quote: RCA's with the... mag-coupled flywheel Century R-6's had magnetic damping, too. But Mark's right, RCA's didn't.  |  IP: Logged Will Kutler Phenomenal Film Handler Posts: 1506 From: Tucson, AZ, USA Registered: Feb 2001 posted 12-04-2004 05:55 PM                     Hi Mark... I need to look at the situation a little closer, but maybe there is the possibility of a machinist being able to design a simple motor-soundhead coupling so that a standard motor could be used? Cheers K.  |  IP: Logged Paul Trimboli Master Film Handler Posts: 274 From: Perth Western Australia Registered: Dec 2002 posted 12-04-2004 08:21 PM                     Will was talking about getting the soundhead powdercoated and have read others talking about it before. How do you deal with covering up parts of the castings like where bearings would be installed? The reason I say this is becuase if you masked the holes up they would then chemically strip it. So do you strip it yourself or do you just got back and mask the holes before its powedercoated? Has anyone powdercoated a Simplex Standard before? Again similiar questions to masking it.  |  IP: Logged Luciano Brigite Master Film Handler Posts: 277 From: Sao Paulo, SP, Brazil Registered: Jan 2002 posted 12-04-2004 08:24 PM                     I worked with Simplex projectors for about 5 years with both SH1XXX and 5 Star soundheads and never had any problem with markings on the film because of their rubber or felt roller. Even on prints that ran for over a month (Ie Titanic) in the same machine then switched to another theatre ,ran for more 3 weeks then back, nothing was detected on the image area.The wear on the film edges was the only noticeably thing on them. To add some insult to it, I got to see a few Simplex and RCA reproducers with the rubber roller and side guides replaced by a one piece,entirely metal roller, yes the part that should be felt or rubber was metal and even that way, did not see damage on the print. Also during all that time never had a gearbox leaking oil in any of them.even on the pair of RCAs I ran recently nor in the 9030 SH I'm rebuilding ATM. Regarding off-the-shelf motors , the 9030 I'm rebuilding, along with everything else (lamp,projection head,pedestal) is driven by a motor of that kind. I just had the motor's shaft redone in a machine shop to get rid of a rudely done job on it. the damaged part of it was cut and a new, longer shaft soldered in place then machined to diameters required to fit the flyweel,some tap'd length for the flyweel retainer and the coupler "star". The coupler is not the original one often found in those heads, the one I have is made of two gear-like machined parts that matchs the same pattern made inside a round nylon block. one part goes on the motor's shaft and the other on the gear box's. once the motor is loose from it's base, pulling it away is all that's needed. the nylon block also comes out and the entire gear box can be removed then .  |  IP: Logged

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