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We installed our new/used 5 deck Christie a few weeks ago and all is well! Last week we had a serious problem and it's now a mystery. We had someone come out and say hat the movie was slowing down and sure enough it was. It was finally down to 1-2 frames per second when we killed it. The platter tension was not the culprit. It's a Brenkert with an RCA sound head. Both were "too hot to handle" or touch! While hot we pulled the "shear pin" and both seemed to be okay. Oil was fine. We let it cool down and everything is now working fine. This scares me! What do you think? Wherein is doom hiding?

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Mike Hurley
www.bigscreenbiz.com

How hot was the projection room? With the recent hot spell on the eastern seaboard (99F in Boston yesterday July 24), is your projection room getting really hot?

Perhaps the added heat caused expansion of some components, leading to binding and additional drag on the drivetrain. It's probably worth having a service engineer visit and give the projector(s) a thorough inspection, looking for any worn or questionable components in the drive. Once friction or drag starts to heat things up beyond normal, the problem just accelerates.

What do you mean the projector and soundhead were okay when you pulled the shear pin? Was neither binding, even when hot? How about the drive motor? Any chance you were having a power "brownout" (low line voltage) with the heat and didn't know it? Lots of air conditioners running in your neighborhood can lower the incoming voltage significantly. If the problem occurs again, get a reading of the voltage supplied to the drive motor.

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John P. Pytlak, Senior Technical Specialist
EI Worldwide Technical Services
Research Labs, Building 69
Eastman Kodak Company
Rochester, NY 14650-1922
Telephone: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
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Website: http://www.kodak.com/go/motion

John has pretty muched covered it. I know when my booth gets over 90 degrees, starnge things start happening. I'd clip a VOM on your outlet plug and see if the voltage is where it is supposed to be (any a/c units or ice machines sharing the circuit?). It's interesting that both the sound head and the projection head where hot. Heat is usually caused by lack of lube (in the projection booth, too). almost every slow projector i've ever encountered has been a lube problem. If both the projector and sound head spun freely when disengaged from the motor, then it seems it's the motor -- and heat does rise. let us know how this works out. good luck.

Could be the drive motor, incoming power line, or a bad circuit breaker (internally burned/pitted contacts).

Was this running with a platter before or on reels?
Remember that the load heat of a bearing will build up over time
It is most likely a bearing that is seizing up increasing the drag on the mech
I would try disconnecting the projector and just running the soundjhead for the same period to rule out one of the possibilities
I am suprised that the mains fuse to the motor didn't blow if it was that slowed down nor that the fireshutter in the projector didn't drop

I have not had the heat prob but have had the slowing down problem. 1 was the motor belt to the drive shaft pulley was about to break. the other was a drive motor failure and Bruce Willis Started sounding like Barry White. Most likely the heat problem was coming off your lamphouse because the shutter was not blocking the heat away. I have had an intermittant leak all its oil and slowly sieze up then burn the motor out.

This may sound stupid...but, you did have your exhaust fan running, right? I had one of my new managers call me at home caying that the projector was real hot and smelled funny. By the time I arrived (5 minutes later), the film gate was soooo hot it was smoking. The manager had been running the system for 2 screenings without having the exhaust fan for the lamphouse turned on. Needless to say, she has gone onto bigger and better things, including employers!

Hooo-boy! Now that is what I call help!

Let me try and answer quests first:

1. neither bound when hot after we removed the shear pin. The motor turned freely also.

2. voltage? would this not have affected all the equip? But again.... there is no ice machine or cooler on this line but perhaps there was a volt problem.

3. this is a platter system

4. I'm surprised by the shutter/mains fuse non action also.

5. I feel that it was something about the bearing and that it will be back to get me.

6. lamphouse was not the problem

7. the elec motor always runs too hot to touch so maybe that was it and why sound and projection heads turned freely on their own?

Thanks to all of you!

[This message has been edited by Mike (edited July 26, 2001).]

Mike I have had the soundhead anti-flutter drum bearing sieze up and slow things down but noe to a crawl. once it siezed up completely all it did was scratch the prints. I had 24 of these dudes go out. I finally figured out what that flintstone car sound was in the soundhead.