Film-Tech Forum ARCHIVE: How to help prevent brainwraps on a speco platter system.

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Posted by Darryl Spicer (Member # 711) on 01-03-2001, 11:43 PM:

Here is an idea for all of you out there who use speco platter systems. I have been doing this for the past two years and have greatly reduced my wraps.

All you need is a full roll of splicing tape or one of the large trailer cores. Not the ones used for feature film cores or the tiny trailer cores.

All you have to do is after you have started the film and the film is running up to speed is place the roll or core into the brain between the little black stopper and the control fingers so the fingers only open up so far. This will help prevent the film from being pulled in between the large roller and the control fingers during a static situation. It does not scratch anything and I have not had any problems with the platter running to slow. If anything I think the platter runs more smoothly.

One note though, Do not use this method if you are interlocking because the takeup is not being used. one platter does not run full speed on a speco when the takeup is not being used.

With the above method and the payout failsafes I installed a year and a half ago static brainwraps are almost a thing of the past at my theater.

Posted by Paul G. Thompson (Member # 655) on 01-04-2001, 12:05 AM:

Hmmmm. I can see where that would work. Sounds like you have some headroom to play with on over-feed. But what about under-feed? Just like me, when you get old, some things seem to slow down. If the film is sticking to itself as it goes into the pay-out head, maybe a little film-guard and cleaning media will correct that.

As a passing note for the Christie Autowind people, I have seen one instance where the excessive head room was caused by stray light sneaking into the modules because someone left a screw out to facilitate a quick module change. (Minot, North Dakota) A test would be if you had a very dimly lit booth. Does it still work properly? If the platter operating characteristics seemed to have changed, it is well worth investigating.

Posted by Paul Konen (Member # 41) on 01-04-2001, 08:08 AM:

Credit for this fix goes to Ethan Harper, fellow Film-Tech'r.

Take a piece of masking tape and double it up to prevent any sticky from showing and make crimp marks about every 1/8 th inch or so.

Attach it to the payout and the first roller to the right of the payout as if you are right in front of it. The crimping allows the arm to fully function and the tape helps prevent the double feeds associated with a wrap.

This was a very helpful solution during our run of SW-EP1 as Film Guard was unavailable then.

Posted by Randy Stankey (Member # 64) on 01-04-2001, 08:44 AM:

My "home base" theatre here in Greensboro, NC has been pretty creative in the Anti-Brainwrap department....

They have been using the roll of splicing tape in the payout arm trick for a while now.

They have also come up with this little jewel to keep the film from double-feeding and getting caught up in the brain rollers...

I thought it was a pretty cute idea.

Posted by Adam Martin (Member # 641) on 01-04-2001, 09:11 AM:

When interlocking with Speco's, I always used the accumulator in my film path to the second projector. After threading, advance the 2nd projector so that the accumulator on the 1st platter is just above the twist. This keeps tension on the long run between the projectors, sets the first platter in "run" mode and gives you some fudge room in case the motors aren't matched.

I've used the splicing tape thing before, too, but only when the PC card was shot and needed to be replaced (and my spare was being used!). (In "run" mode there was no speed control: on or off!)

Posted by Darryl Spicer (Member # 711) on 01-04-2001, 09:22 AM:

Well, our speco platter systems are 11 years old now and I have not noticed anything slowing down. the payout and the takeup sort of work together and if a payout stops working I just replace the controle card. In my eight years of useing speco platters I have had to do far less maintenace on them than the eight years of useing christie. I am not saying christie is a bad platter system you just have to tweak them more often.

Posted by Darryl Spicer (Member # 711) on 01-04-2001, 09:34 AM:

yes you can use the variac to act as a loop acumulater. but I prefer the large wall acumulater for long distances. at one of our sister theaters I tried to help them set up an interlock for a dark time screening. Everything woul run fine but the variac would start dropping on the first projector. At first I thought it was the long distance between the two projectors but after investigating I found that at some point in time the projector motor had been replaced and it was running just slightly faster. it is a syncronized motor but I guess the motor on the othe machine was running a little slow. Sounds like the age thing that Paul was talking about.

Posted by Greg Pauley (Member # 503) on 01-04-2001, 09:49 AM:

I recently purchased the removable brain kit for all of my speco platters and would highly recommend them to all. They eliminate the problems mentioned above and they have replaced the shallow head screws that hold the magnet and rollers in place with a nice hex head screw which you can tighten down without stripping. Being able to remove the brain when moving prints eliminates alot of repairs! I agree with Darryl, the speco platters are ugly and outdated, but they continue to work. I posted a nice fix for the rods on the specos "Speco LP-270 Fix" back on 6/24/2000 for any new members not around at that time.

Posted by John Pytlak (Member # 331) on 01-04-2001, 09:49 AM:

Good suggestions, all.

Even though Kodak VISION Color Print film has a conductive antistatic backing, the film must be in contact with a conductive surface so there is a path to ground for any static buildup. Non-conductive painted, plastic or anodized platters and rollers should be periodically treated with a topical conductive antistat like "Static Guard", "Endust for Electronics", "ACL Staticide", or other antistat used for clothing or electronics. AFAIK, Kelmar now sells a conductive "Platter Mat", similar in concept to the conductive floor mats used in electronics assembly areas to prevent buildup of static charge from "zapping" sensitive electronic components. Kinetronics, Meech and Simco sell static control equipment like conductive fiber brushes and antistatic ionizers.

Maintaining the recommended 50-60 percent humidity in the projection room also helps reduce the static problems caused by dry winter heat.

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com