Film-Tech Forum ARCHIVE: Perforated Scratch. Please help

This is topic Perforated Scratch. Please help in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Jack Terrell (Member # 6250) on 04-24-2011, 09:02 PM:

I am having a very annoying scratch problem. One of our projectors (simplex 35 and 5 star sound head) is putting a vertical scratch down the left of center of the frame (with the sound line that is actually about the center of the film). The scratch is white-ish and it is intermittent - meaning it looks like a perforated line cut on a piece of paper. The scratch takes about a week to show.

My first thought is that it is a roller or sprocket 'poking' the film at every revolution. Although, rollers aren't suppose to touch that part of the film, and all of the rollers seem in fine condition. In fact, I recently cleaned or replaced all of the rollers on the christe autowind 3. I did this when I first became projection manager at this location, and the scratch may have coincided with the cleaning.... because no one noticed the scratch before.

If anyone has seen this before, please help!! a quarter of my prints have this scratch now! The only option i see is to replace each roller/sprocket one by one and wait a week to see if the print scratches....

Posted by Stephen Cattenazzi (Member # 2214) on 04-24-2011, 10:52 PM:

We had something similar where I am (although different equipment). I actually found a piece of splicing tape had come off the film, and got stuck onto the bracket holding the top feed roller leading to the top of the projector head. I'm not familiar with your equip. so this might be pointless for you. But thought it might be worth a mention.

Posted by Randy Stankey (Member # 64) on 04-25-2011, 12:17 AM:

White scratches are usually emulsion side scratches.

This theoretically eliminates pad rollers but it leaves the possibility of the problem being caused by any of the four sprockets or the sound drum.

Go down through the projector's film path, one piece at a time and inspect for problems as you go. (Be the film.)

I'm going to ask a wild-ass question: Do you clean projectors with a toothbrush?

It is common for bristles to be pulled out of the toothbrush and get caught in the projector sprockets. Every time the sprocket makes a rotation, that piece of bristle slaps against the film and, over time, makes marks.

Another place where problems can happen is on the sound drum.
If a piece of crud gets on the drum (or on either of the metal film rollers in the sound head) it can cause scratches.

Third thing to look at is to make sure everybody who uses the projector is threading it correctly.

If you make your bottom, intermittent loop too large it can slap against the back of the projector bulkhead and cause scratches. The reason why it seems to take a week to appear is because only one person is making this fuck-up.

It might pay you to go through your employee schedule and see if you can correlate your scratching problems with one particular person's shifts.

You do keep a booth log book... Don't you?

Posted by Jack Terrell (Member # 6250) on 04-25-2011, 12:37 AM:

Thanks for your reply

I have inspected the four sprocket, pretty closely, maybe I should get out my magnifying glass... The boothers used tooth brushes before i got there. I switched em to metal bristles - which could be worse... I will look for that. Its hard to get a good look at the sound drum and lateral guide roller, but i will look closer. I have been focusing mostly on the rollers that I replaced.

I have noticed that others loop their lower intermittent loop too big, but I have isolated this to only prints that spend time on projector 2, so unless there is something on that bulkhead wall when it slaps, I don't think that it is the problem. But it could be other threading issues, like incorrect damper tension, which could cause the film to pull against the sprockets and maybe cause contact in the center part of the film, especially on the sound drum, which is right above the damper roller. Perhaps farfetched.

I also noticed that one of the pad rollers does not turn freely with the film. ?

Posted by Chase Pickett (Member # 5975) on 04-25-2011, 12:38 AM:

There are two things I think could be the problem. First, check the pad roller on the 5 star sound drum, and make it as clean as possible, no matter what it takes. In fact, I would recommend the tip for eliminating that rubber pad roller all together. It's named "how to make a simplex 5 star sound head more film friendly" under the tips in the warehouse. Second, make sure the lateral guide rollers right above the film gate are spinning properly, if not the film could be bending toward the film gate scratching the film ever so slightly and intermittently. Clean and lube if needed. Actually just clean and lube it anyways. Couldn't hurt right? Hope this helps -Chase

Posted by Joe Redifer (Member # 3) on 04-25-2011, 01:07 AM:

Do you have any fairly tight twists in your film path? I wasn't getting quite what you describe, but a looong time ago I was getting green specks in the formation of a line left of center after a print played in an auditorium for a while. The twist coming out of the bottom of the sound head going to the lower magazine roller was too extreme, so I made sure it was as relaxed as possible. No more scratches in that auditorium, ever.

Posted by Jack Terrell (Member # 6250) on 04-25-2011, 01:21 AM:

That does sound like what I'm getting. They are green or white - clearly emulsion side. It twists a little coming off the failsafe to the first roller, but not too extreme.

Posted by Joe Redifer (Member # 3) on 04-25-2011, 01:28 AM:

Straighten it out as much as you can and see what happens to future prints after they have been in that auditorium for a week or two (it usually took a couple of weeks for the scratch to show up on mine). Ideally, the roller will be directly underneath the roller where it comes out of the failsafe, not angled forward or back. If you can't do this, just try to make it as nice as possible.

Posted by Randy Stankey (Member # 64) on 04-25-2011, 08:47 AM:

I hardly use any brushes.

I use a soft bristle paint brush to occasionally clean in hard to reach areas but 90% of the time I just use a shop rag to clean the inside of the projector. But I also use FilmGuard 100% of the time so projector cleaning is greatly simplified for me.

I wouldn't ever use a metal brush inside the projector.

Yes, check the damper arm and roller in the sound head. I sort of just assumed that was understood when I was talking about the sound drum.
(Telegraphic language... [uhoh]

)

Posted by Louis Bornwasser (Member # 3063) on 04-25-2011, 09:13 AM:

I think you may have Strong or Potts platters. If so, someone missed one of the rollers on the up/down carriage. The "left of center" mark is made by the edge of the small plastic or metal button in the carriage.

East to prove; make a loop of newer junk trailer and deliberately misthread. Look for increasing damage. Louis

Posted by Monte L Fullmer (Member # 2797) on 04-25-2011, 10:26 AM:

If this will help any, I posted this back in 2006 .. see what you think and good luck in finding the scratching issue - Monte

Perfect threading

Posted by Jack Terrell (Member # 6250) on 04-25-2011, 12:24 PM:

So here is what i did, and I will let ya'll know if the print that just got put in there is scratched in a week or two.

The twist coming off of the failsafe to the lower roller was more extreme than i thought. it was causing the film to awkwardly position itself to the two rollers, which caused light contact of the non-edge parts of the film.

The next thing I did was remove a ton of plastic fibers from the lateral guide roller on the sound drum. They were wrapped around the roller, between the friction roller and the outboard assembly piece of the roller. there were about 20-30 pieces, and they were about 1-2 inches long; white nylon? And many were slapping against the film or stuck to the surface of the friction roller - which by the way I do want to do that mod to replace that stupid thing!. I cant imagine where these pieces of fiber came from. They seem like nylon. They're too big to be tooth brush fibers. They did vary in length. perhaps they're strand of nylon that peeled off of the pad roller that doesn't spin freely - it is right above this assembly. Must replace/lube asap.

My money is on the fibers. But we'll see in a week or two. Thank you so much for your help guys! [Smile]

Posted by Brad Miller (Member # 2) on 04-25-2011, 01:25 PM:

Yup, its that stupid soundhead design coming back to damage more prints. I said "that's the stupidest design ever" back when I first saw it on an RCA "boat anchor" soundhead eeons ago and I still feel that way to this day.

The prints that damn thing is scratching will probably be the ones randomly selected to keep for repertory shows at the depot too. Even if somebody at the depot cared to look at the print, the damage those rollers cause are usually very difficult to see without being projected.

Someone will undoubtedly come on after me whining that the design is wonderful and the operator isn't keeping it clean, but regardless the design is stupid because it forces people to keep them perfectly clean all the time, and with platters running a couple of miles of film through the soundhead at one time, the embedding of dirt is pretty much a given.

Case in point, when I first started to work at the UA Berkeley in 1993, their projectors had not been cleaned since they opened in 1986. Seriously. There was so much gunk caked onto the sprockets that the teeth were BARELY discernable sticking out from the hardened dirt. They had 7 Simplexes and 1 Century. The print on the Century had been running for 2, maybe 2.5 months exclusively in that auditorium and other than dirt buildup at the reel changes looked essentially new. All of the other prints (ran on those damned Simplex soundheads) were essentially unwatchable even in the middle of the reel. Even a print they had only been running for ONE WEEK looked terrible.

Sure that is an extreme example, but it does prove how awful the Simplex/RCA soundhead design is.

Posted by Randy Stankey (Member # 64) on 04-25-2011, 07:13 PM:

Remember, toothbrush bristles are twice as long as you think they are.

Toothbrushes are made by embedding the middle of the fiber into the plastic handle then cutting off the brushes so they are even. Each single bristle is actually kind of shaped like a letter "V."

When bristles pull out of a toothbrush they'll be 1-1/2 or 2 inches long.

This problem will go away if you stop using toothbrushes to clean projectors.

Use a red shop rag and do it EVERY time you thread the machine.
If done conscientiously, you will not need to use a toothbrush because your projector will always be clean. You will only need to do major cleanouts once or twice a week, depending on the amount of film you run.

In a 20 screen theater where I once worked, there was 1 guy per shift on weekdays and 2 guys per shift on weekends/holidays.

We had a rule, each person had to do a full cleanout of one projector each shift. If everybody held up his end of the deal, each projector got a full cleaning once per week. As long as projectors got a wipe every time they were threaded, no more work was needed but, if people started getting lazy, projectors would get filthy in no time at all. By the time the end of the week rolled around, they were full of dust and the rails were all covered in baked on crap.

My advice: Toss out the toothbrushes and keep, maybe, one or two on hand in the supply cabinet for use when you need them.

If you use FilmGuard on every show, you can even skip a cleaning and the projectors will still look good and run well! [thumbsup]

Posted by Jack Terrell (Member # 6250) on 04-25-2011, 07:31 PM:

Maybe I should start a new tread for this, but in keeping with the last coment, what is the best recommendation to clean out a not so well maintained projector. The components, for the most part (present discussion excluded) are cleanish, but the walls and hard to reach areas are covered in a wetish oily gunky stuff. I'd love to just wipe it out, but it's hard to reach. Would you all suggest just getting what I can, or actually removing components and wiping the walls?

Posted by Randy Stankey (Member # 64) on 04-25-2011, 08:18 PM:

You could take out all the sprockets and pad rollers but it is such a PITA to do and to get them all back in and aligned correctly that it isn't worth doing, especially when you have several projectors to clean.

Just get in there with a shop rag and do the best you can. You can wrap the end of the rag around the end of a pencil or something if it helps.

If it's any consolation, a bit of dirt or grease hiding in the nooks and crannies isn't going to kill you so long as the rest of the projector is clean and you take care of the sprockets, pad rollers, gate and sound drum, etc.

If you clean a little bit every day, eventually, you will get most of the crud out of the projector. The key to keeping them clean is consistency.

If you clean a little every day, you will end up doing LESS work in the long run because the projectors never even get dirty in the first place.

If you let the projectors get dirty you will find an endless supply of dirty, greasy crap hiding in every conceivable place. You will spend an eternity cleaning them and you will seemingly never get it all.

My best advice is to do what I said above. Do a major cleanout, first. Then, make sure the projectors are wiped out before every show.
(This takes, literally, 30 seconds.)
Each operator who works a shift is responsible for taking apart one projector and cleaning it, top to bottom before he goes home.

If there are two shifts per day, that means that 14 projectors will get cleaned once per week in addition to the pre-show wiping. If you have fewer than 14 machines then each projector will get cleaned even more often. If there are more than 14 you might have to assign two projectors to clean per shift. You do the math and figure out a system to suit your situation.

I used to have a couple of theaters on my route near Atlanta. If the kids who run your booth are anything like the kids who ran mine they must be driving you crazy!

All I can say is that you need to institute this policy and stick to it.

Kill one of them and leave the bloody and broken body lying in the middle of the booth floor with a sign written in his blood, "Didn't clean the projectors like I told him!" [evil]

They'll get the message right quick! [Wink]

Kidding aside, if you institute a cleaning policy like I suggest (or one of your own design) your operators will find out that they are doing LESS work and they will be doing a better job as well! [thumbsup]

Posted by Tony Gallimore (Member # 5358) on 04-25-2011, 09:56 PM:

Jack,

I know many will cringe at the thought just as I did at first... but several years ago I was told as projectionist to wash the machines down if they had accumulated gum and grime with auto engine degreaser. The gentleman who told me to do this was owner of the theatre and had owned several screens for a number of years. To my surprise the inside paint job looked like new after a good wipe down. Now, understand I avoided directing the degreaser toward bearings, the slit lens and any lubricated moving parts. We were also running Century heads rather than Simplex. I was completely blown away at the great job it did. One must only be careful to not to get it on parts that need to remain lubricated. I would give it an A+ for cleaning the inside casement, but do so carefully.

Posted by Randy Stankey (Member # 64) on 04-25-2011, 10:11 PM:

The reason Simplex never made a digital projector is because they couldn't figure out how to make them leak oil. [Wink]

Most Simplexes are just going to leak a little bit of oil and that's that. Sure you can do all sorts of things to stop them leaking but most people don't. The inside of a Simplex is just going to have some oil in it.

As long as you keep the rest of the projector clean a few drops of oil isn't going to kill you.

Do I like it? No! But that's just the way it is. Your best defense is to stay in front of the ball in the first place.

Sure, you can use degreaser. But I would recommend you apply it to a rag and wipe in inside the projector. One wrong spray and you could end up causing big problems.

Posted by Jack Terrell (Member # 6250) on 04-26-2011, 12:14 AM:

It would be nice to have the simplexes look all shiny, but I don't want to either dry out anything or have to realign everything.

I have set up a task list where one projector gets cleaned a day between two projectionist. I split it so that one person detail cleans the heads and the motor and the other wipes the chasis, dusts, wipes rollers brains and platters and checks auditorium quality, bulbs etc. And then there's additional tasks to keep the booth clean. I did this because the quality of cleaning was so poor, so I in effect slowed em down. Hopefully it's a temporary measure.

Also, we blow the projectors with canned air instead of wipe at every thread. Any thoughts? We want to get an air compressor to save on cost. Also, one of my guys wants to open the lamphouse and vacuum dust and "clean" inside. This makes me nervous. Should I be?

Posted by Martin McCaffery (Member # 37) on 04-26-2011, 08:40 AM:

Randy's advice for cleaning is all good, but let me add the obvious:

Do not try to clean, especially with a rag, when the machine is running!

I know, it sounds idiotic, but remember: Nothing is idiot proof because idiots are just so damned ingenious.

Posted by Randy Stankey (Member # 64) on 04-26-2011, 10:08 AM:

Canned air or air compressors are one of those things that I only use occasionally.

It's good for getting dust out of nooks and crannies or for dusting photographic negatives, etc., but it's not good for general use.

There are three things you have to be careful about when you use air to clean:

1) It can blow dirt farther INTO the machine. 90% of the dirt goes out of the machine but the other 10% gets impacted into the bearings and moving parts. You have to watch out where you aim the nozzle to prevent this.

2) The stream of air can contain microscopic particles of dust and water.
Remember, when you compress air you are also compressing the water vapor in the air. That vapor turns back into liquid and gets carried right along with the stream. Tiny, little particles of dust and water vapor are getting blown at a speed of 1,000 MPH directly into the surface of the object you are trying to clean. You are basically sand blasting your projectors. You can put water traps and dust filters on your compressor but it just adds more expense and trouble.

3) When you blow all that dust and dirt out of a projector, where does it go? It doesn't disappear. It goes up in the air. Then, later, it settles somewhere... all over everything else in the booth. It gets pulled into your amplifiers and sound gear. It coats the top of the projector, lamphouse and goes all over your booth windows.

Using air to clean is fine for small things. Carefully blowing dust off a lens or blasting water out of a small part you are trying to clean but, for general cleaning, using air actually makes MORE work than it saves.

Besides, shop rags are cheap. If you look around at the auto parts stores and places like that, you can find them by the bundle for about $20. Just use them and throw them away if you want. If you want to launder them and use them again, have your boss give you $5.00 out of office supplies money and take them to the local laundromat. (Do this at night!)

I've got an old Simplex. It looks like Hell to me. I grew up looking at brand new, shiny projectors. Grungy, old projectors just make me cringe. I know that the film-bearing parts are all clean and they work just the way I want them to but that little puddle of oil inside the projector still makes the hair on the back of my neck stand up every time I see it. I just have to resign myself that this projector is always going to be like this and I just have to keep cleaning it.

In all this time, the best thing I have found to keep them clean is persistence. The good news is that persistence doesn't cost anything. Bosses like it when you don't spend money! [Wink]

If your guy wants to clean out the inside of the lamphouses, there's nothing wrong with that if he can do it without killing himself or damaging the machine.

To be honest, I can buy another machine but, if the kid kills himself, I have to do a whole lot of paperwork! [Wink]

You know your guy better than I do. If he can do the job well and do it right, it's probably high time the inside of the lamphouses got cleaned.

Carefully clean the reflectors with 90% alcohol but be sure not to touch the xenon lamps. Use a rag to wipe out the dust on the rest of the surfaces. A little bit of "Formula 409" won't hurt if you keep it away from the electrical parts. A vacuum cleaner is all right if the lamphouse is really dirty but, as always, be really careful!

Like Martin says: Turn off the power whenever your hands or anything but film are inside the projector! If you are doing anything more involved than threading or normally operating the projector, turn off the breakers.

I don't mind cleaning up the blood as much as I hate doing paperwork! [Wink]

Posted by Ian Parfrey (Member # 5122) on 04-26-2011, 04:44 PM:

....and if your guys are inside the lamphouse, PUT THE PROTECTIVE COVER OVER THE LAMP and wear the BALLISTIC P.P.E! (Personal Protective Equipment)
Xenons can make a hell of a mess when they go off and your guys DO NOT want to be unprotected when inside there if the lamp decides to [bs]

itself.

As Randy said, the paperwork is horrendous quite apart from eating into after hours drinking time [beer]

Posted by Robert Koch (Member # 3728) on 05-01-2011, 08:31 PM:

"Someone will undoubtedly come on after me whining that the design is wonderful and the operator isn't keeping it clean, but regardless the design is stupid because it forces people to keep them perfectly clean all the time, and with platters running a couple of miles of film through the soundhead at one time, the embedding of dirt is pretty much a given".
The above from your letter pretty much says it all. This was designed long before you were born and I was still in Jr High school. Different era. Projectionist were still getting shipments on 1000 foot reels and doubling them up,a practice somme frowned upon. The concept of running miles of film thru one reproducer and projecting into 14 200 seat auditoriums presidrd over by concession stand personnel was certainly not even considered as possible in 1936.Or sure as hell not probable In that day they only had 2 projectors and reproducers to keep clean and plenty of time to clean while one projector was idle.
If this is whining so be it.You and I both know the powers that be do not want to have anything to do with advancing technology in the projection room Thats as true now as it was when I still had all black hair. You know it and I know it. It all comes down to paying a design team to put a great deal of expense and effort into something these bastards won`t buy anyway.
To coin a phrase I think you are beating a dead horse. As you state this was never designed for what it is expected to do now..

Posted by Brad Miller (Member # 2) on 05-01-2011, 08:41 PM:

Robert, apparently I was not clear enough. There are many other GOOD soundhead designs out there (Century, Cinemeccannica, Kinoton, etc). There is no excuse why these soundhead designs were not retired 30+ years ago when large reels and platters became the standard.

Posted by Louis Bornwasser (Member # 3063) on 05-02-2011, 12:39 PM:

Back on topic: is this guy's problem resolved? I still think it is platter misthreading.

As regards RCA/Simplex, While we are primarily Century, the few Simplexes and RCAs around here do not have a problem with destroying film. Wow & flutter, perhaps, but not damage. w&f are unavoidable with the design; the much superior Davis bridge having been patented by Cetury/Westrex. Again, proper maintneance and instruction yield good results. Not hard really! Louis