Film-Tech Forum ARCHIVE: STRANGE SPECO LP270 PROBLEM

This is topic STRANGE SPECO LP270 PROBLEM in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Dennis Lunt (Member # 1224) on 07-23-2003, 11:26 AM:

We have an 8 plex running with new standard LP-270's. Two of the platters appear to be winding the film so tightly onto the take up ring that the film and ring eventually telescopes up off the platter and the pins let go of the deck. If you feel the tension of the film as it comes down the column just before the film goes to the platter entrance roller as compared to the other platters in the facility the tension seems to be exactly the same...the other six platters do not exibit this problem. Everything on the platter appears to be normal... all rollers are turning freely and the take up speed assy. also seems to be just fine and is running in the center of its travel and no binding etc. The take up rings are the new style cast rings. Has any one else experienced this problem?
Mark @ CLACO

Posted by Brad Miller (Member # 2) on 07-23-2003, 11:51 AM:

So is this Mark or Dennis?

Sounds to me like the final roller in the chain is riding too low toward the platter surface, causing the film to be pushed upward as it stands upright. The film shouldn't come into contact with the platter deck until it is fully upright, but non-AW3 systems don't have much adjustment if any for this. It would occur on oil soaked prints. Got a leaky projector?

Posted by Mike Blakesley (Member # 26) on 07-23-2003, 12:32 PM:

Brad - I'd bet it's Mark using Dennis's computer.

Dennis is usually a pretty quiet guy unless he's trying to sell you something! [Big Grin]

Posted by Darryl Spicer (Member # 711) on 07-23-2003, 12:43 PM:

The only time I have ever seen what you describe is when one side of the film developes a crease in it over the sprocket hole area. Try winding the film with soundtrack down and see what happens.

Posted by John Pytlak (Member # 331) on 07-23-2003, 01:54 PM:

I also vote for the possibility that one side of the print has been damaged in some way (roping, crease, perf nicks, stretching) that makes one side a bit "thicker" so it cones when winding.

Posted by Dennis Lunt (Member # 1224) on 07-23-2003, 02:10 PM:

That was Mark on my computer here at the office. And thanks for your input so far.

Dennis

Posted by Bill Langfield (Member # 818) on 07-23-2003, 03:04 PM:

Hey Mark/Dennis,

I think you'll find that the take-up elevator needs a clean and light oiling. (Ive had the exact same problem on the newer Specos)

Easy Check: Although banned, first try hitting the vertical shaft with some WD-40 and see what effect that has. Then clean and lightly oil.

You never mentioned if the problem is present with prints that work OK on the other platters. IE Do prints that take up OK on other platters screw up on this one?

Bill.

Posted by Darryl Spicer (Member # 711) on 07-23-2003, 06:19 PM:

I don't see how the variac would have anything to do with the problem that was described above. Normaly variac issues are the film drooping at start up or worse case wanting to run into the floor because the accumulator sticks. I wouldn't use WD-40 on those I would use a light coating of projector oil on them. Check for something in the film path possably causing damage to the prints.

Posted by Paul G. Thompson (Member # 655) on 07-23-2003, 08:43 PM:

I have also seen this happen on a Xetron XNR platter. It was caused by two things....oily film and the roller that guides the film on the platter was grossly out of alignment. (too high)

I don't think it is winding too tight. The LP-270 is a variac based platter, and the take-up tension is controlled by the position of the elevator, just like Potts, A3's, Xetron XNR series and some others as well.

Daryl has a good point. If the guide rod and the twist rod are plugged with WD40 residue, they will stick. It could be sticking in such a manner that it is applying more power to the take-up motor than it requires.

If you are using WD-40 on the twist and guide rod, discontinue using it immediately. The manual is wrong. The manual was written well before it was discovered how bad WD-40 is on the equipment. Once you get the rods cleaned up, you should be OK on that aspect.

Some may disagree with me, but I never oiled them. I just keep them clean. The twist rod guides are made out of Teflon or some type of plastic and the bushing on the guide rod is made of the same material and should not need oiling.

Posted by Gordon McLeod (Member # 33) on 07-23-2003, 08:44 PM:

The variac controls the power to the motor and there fore it's torque and therefore its speed. The drag on the system which is the weight of the film, the drag on the rollers and and the weight of the elevator all add to the load and as such the tension on takeup

Posted by Brad Miller (Member # 2) on 07-23-2003, 08:50 PM:

Interesting point Gordon just made...check and make sure all of the rollers in the takeup path are spinning freely. Frequently I found those split rollers were too close together, or worse someone decided to lubricate the shafts that the rollers spin on causing problems.

Posted by Paul G. Thompson (Member # 655) on 07-23-2003, 08:52 PM:

Gordon is correct. Also, take Brad's suggestion about making sure all the rollers are not gummed up and are rotating freely.

Posted by Randy Stankey (Member # 64) on 07-23-2003, 10:13 PM:

Yes, you can adjust the height on Specos. First, there are a couple of wing nuts on the bracket that holds the take up roller. Second you can adjust the whole assembly similar to the way the Christie platters adjust. The difference is that you don't get so much travel.

I'd say, make sure everything is clean and spinning/sliding freely. Then I'd check the "zero" adjust on the variac. After that I'd be sure that the film isn't damaged. (Then, again, film damage is easy to check for... Check the easiest things first, I always say! [Smile]

)

Posted by Richard B. Perrine (Member # 409) on 07-24-2003, 01:59 AM:

I'd check the coupling between the variac and the twisted rod.
Make sure it'sin the same position as the platters that are running correctly....ie the variac brush position and rod when the roller is unthreaded.
Second ...try a different ring...a slightly warped ring can give you problems.

RBPerrine@aol.com

Posted by Mark Gulbrandsen (Member # 72) on 07-26-2003, 11:35 AM:

Thanks for all the tips. These are brand new platters with about a month of use on them. I will return to the site on Tuesday to see if lubing the elevator related parts will help out as well as look into more critical adjustment of the platter feed roller. Its odd that these are the only two in the booth that have this problem. The others wind the film so nicely that its like a sheet of glass!
Things I definately know ARE NOT causing this.....
Variac coupling being loose of out of adjuatment, sticky, or sticking rollers, damaged film.

Mark @ CLACO

Posted by Mark Gulbrandsen (Member # 72) on 07-29-2003, 08:32 PM:

We concluded that the print stock does indeed have some sort of problem causing it to not wind properly. Winding it soundtrack down made the situation better and kept the ring from lifting out completely. The print has been played in three different houses with the problem following the print around. New films replaced the other one having the same problem("Rediclously Blond" or what ever it was) and not a problem was found with those.
Mark @ CLACO

Posted by Larry Zuverink (Member # 1483) on 08-04-2003, 10:50 AM:

We have several locations with Speco's. Some clean the shafts and elevator with alcohol. Some places lube and some don't. The places that do, use 100% Silicone (similar bottle to WD40). WD40 eats anything plastic or rubber.