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Author Topic: "Motorboating" with Simplex soundhead Gary Crawford Expert Film Handler Posts: 200 From: Neptune NJ USA Registered: Nov 2003 posted 04-28-2004 01:38 PM                     A recent problem with an older Simplex SH1000 optical soundhead. It seems the lateral guide roller will sometimes allow Dolby or another soundtrack to get close enough to the light path where it will "motorboat." I found that pushing on the inside edge of the guide roller "guard rail" will let the film ride where it's supposed to. My relief man didn't know that trick. The roller has a very small amount of side play but will run okay once you adjust it. I also noticed that a quick tap of the edge of the film with my fingernail will put it back where it belongs. It hasn't gotten any worse, but what are the long-term potential problems? Need a new lateral guide roller maybe? Thanks...Gary  |  IP: Logged Dominic Espinosa Phenomenal Film Handler Posts: 1172 From: Boulder Creek, CA. Registered: Jan 2004 posted 04-28-2004 02:10 PM                     I would check that the flange on the guide roller isn't worn or anything, this could point to a long-term misallignment. I noticed this sort of problem on one of mine once when the nut that retains it became slightly loose. Check to see if the roller is allowing the film to slip, or if it's guiding it off in one direction or the other. Unless you've got a different head than I'm thinking of there shouldn't be any play whatsoever on that roller.  |  IP: Logged Gary Crawford Expert Film Handler Posts: 200 From: Neptune NJ USA Registered: Nov 2003 posted 04-28-2004 02:22 PM                     Thank you Dominic. From what I can see, the roller has a very slight side play, mere millimeters if that, but just enough to let the film run off enough to allow the Dolby track to scan in the exciter path. The roller edges seem okay (I didn't mic them) and are not pizza-cutter sharp. Once I push it inward it clamps down on the film just fine and the whole reel runs like it's supposed to. I'm thinking maybe a small adjustment is the problem but I haven't found it yet.  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 04-28-2004 02:41 PM                     I suggest that the lateral guide and associated parts be given a good cleaning and realignment. Replace any worn or damaged parts. One thing that I have found is that people apply WD-40 or other unsuitable lubricants to the lateral guide's shaft. Over time, the stuff hardens or gathers dirt and starts to get stiff. The lateral guide holds its place by spring pressure against the adjustment knob. Same thing goes for the flanges on the sides of the roller. Every time you thread the proejector you unconsciously move those parts side to side. It may not be very much but it doesn't have to be. Tolerances are tight in there. Now, if the parts are dirty, worn or not assembled correctly, the springs won't be able to push their associated parts back into the correct position. If those parts aren't in the right position, the film won't be in the right position. And, of course, if the film isn't right, the sound won't be right. A cleaning, check and realignment of the lateral guide assembly will allow all of these parts to "float" around the way they need to and find their "home" positions after you thread the projector. If you are careful when you disassemble, you should be able to get everything back together again without needing to perform a full A-Chain alignment. (At least not right away.) If done carefully all you should need is a piece of Buzz Track film to reset the lateral alignment. If you accidentally bump the cell/CCD or the slit lens and knock them out of whack, you'll have a problem on your hands. You probably won't be able to solve it without a full A-Chain. If you don't have the equipment, you are screwed. When you clean that shaft and assocated parts, be sure to get all the old, crusty oil or grease out. I don't believe the thing needs lube at all but if you feel the need to lube it, use one or two drops of 3-In-1 or similar.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 04-28-2004 02:46 PM                     "When you clean that shaft and assocated parts, be sure to get all the old, crusty oil or grease out. I don't believe the thing needs lube at all but if you feel the need to lube it, use one or two drops of 3-In-1 or similar." Randy, Shame, shame, shame!!! I bet thet you also carry a can of WD-40 with you on your calls...... This is THE MOST COMMON problem with sound reproducers that use a spring loaded flange!!!! The oil evaporates and leaves a film of goo. Realistically...... ONLY use some sort of light synthetic oil on the lateral guide shaft and parts....3 in 1 will evaporate before you get home that night and you'll be stuck again!! 3 in 1 is crap oil of the highest magnitude.  |  IP: Logged Gary Crawford Expert Film Handler Posts: 200 From: Neptune NJ USA Registered: Nov 2003 posted 04-28-2004 02:47 PM                     Thank you Randy and Mark. I'll see what I can find tonight. These are old machines here and they do need TLC but problems are few and far between.  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 04-28-2004 02:56 PM                        Mark -- what kind of "light synthetic oil" is best for this? Would Century projector oil work? I run a pair of SH-1000s from time to time, though I haven't had this problem (yet).  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 04-28-2004 03:16 PM                     No, I don't lube those parts, nor do I use WD-40 very often at all. (A can of WD-40 and a cigarette lighter makes a great flame thrower! ) I suppose I should rephrase and say that *IF* you feel the need to lube those parts a light oil that won't gum up is the thing to use. I don't remember the brand but I remember a certain kind of gun lube that worked really well. You were supposed to use a small amount of the stuff and wipe off the excess before assembling the parts. It worked great even when temperatures went below freezing. Other lubes would get sticky when cold. This stuff supposedly worked when temperatures were below zero. The only thing I remember is that it had a very "sweet" smell to it. I think it had Teflon in it or something.  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 04-28-2004 03:47 PM                    Amazing that these machines ran for six decades without synthetic oil. Randy, I think you're thinking of Tri-Flow which has a peculiar banana scent to it. We used to use it on the heated printhead of Acmade edge numbering machines.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 04-28-2004 04:07 PM                     Steve said...... "Amazing that these machines ran for six decades without synthetic oil." Actually they didn't run for six decades without alot of assistance. The majority of them had regular maintainance from RCA Service, ALTEC Service and many other servicing agents while you were growing up and watching movies at Park Forest Mall and film was being done right. Indeed some theatres running these reproducers even had monthly service contracts in busy locations in large citys. Aside from the fact that they were the best reproducers made the frequent service is really why they are still with us. On a first time service run the last two weeks through Wyoming and Montana out of 14 locations there were 5 stuck lateral guide rollers and two completely frozen lateral guide assys. with stuck bearings and the shaft trying to spin in the bore of the bearings!! I wonder how much film these reproducers scratched???? Its best to coat shafts and other parts excluding rubber surfaces with a light film of oil and yes, projector oil is ok.... Living in a very dry climate I just happen to prefer synthetics as they don't evaporate at all and the lateral guide roller will run longer without attention.... some of our customers only have yearly service done. You will also have far less corrosion in humid areas. Either the LaVezzi oil which comes in a convenient 4 ounce bottle or the lightest grade of Mobil-1 is fine. I believe its only available in multi grade from AP stores but the 10-30 works very good... The LaVezzi is around 20 weight straight synthetic, probably nothing more than a good grade of compressor oil. I also coat all shafts and bearings of ANYTHING that I am assembling, or re-assembling with Mobil-1 as it allows the assy. to come apart much much easier years later as the oil is still flowing and not a sticky dried up film!! Bearings will slide right off the shafts, etc years later. Mark  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 04-28-2004 04:49 PM                     That's the stuff! Tri-Flow! Thanks for jogging the memory, Steve!  |  IP: Logged Bill Enos Film God Posts: 2081 From: Richmond, Virginia, USA Registered: Apr 2000 posted 04-28-2004 05:31 PM                     About 15 years ago when I was servicing office machines, IBM Selectrics in particular, we tried Triflow on the print shafts of these machines. The print shaft is the shaft that the carrier rides on. Triflow was very slick at first, but in about a month it gummed so badly that the carriers were moving very sluggishly, we got recalls on every machine treated with this stuff. Mayonnaise would be better, and at least you could put it on a sandwich. On our SH1000s I wipe the guide roller shafts with projector oil when I assemble them, never had a problem in 18 years, it probably serves only to prevent rust.  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 04-28-2004 06:44 PM                    Re: 18 years, 15 years: No wonder those typewriters were malfunctioning...they'd been serviced by a projector technician! They shoulda called a typewriter expert!  |  IP: Logged Christopher Seo Jedi Master Film Handler Posts: 530 From: Los Angeles, CA Registered: Jun 99 posted 04-28-2004 09:36 PM                     FWIW, I used Tri-Flow to lube the lateral guide roller shaft of an RCA 1040 and it's still running fine after over half a year.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 04-28-2004 11:38 PM                     Some day perhaps some of you will deal with the hundreds of these reproducers that I do every year. Then you will understand the meaning of synthetic!! Mark  |  IP: Logged

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