Film-Tech Forum ARCHIVE: Repair those Christie dousers

This is topic Repair those Christie dousers in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Brad Miller (Member # 2) on 09-04-2000, 05:48 PM:

Anyone with a Christie projector is probably all too familiar with having to purchase new dousers because their existing ones burn and warp to the point they jam in the slot. Next time that happens, try this little tip I discovered:

Remove the douser as you normally would (lots of cussing and struggling). Then, flip the douser around and lay it so the lens side of it is now facing the lamp. Look at this picture below for the proper placement.

Now fire that lamp! Let it burn that douser for 5 minutes.

After 5 minutes have passed, turn off the lamp and WITH A PAIR OF PLIERS remove the douser. DO NOT TOUCH THE DOUSER WITH YOUR BARE HANDS! Go to your stairway and lay the warped and blazing hot douser on one of the steps and give it a couple of whacks with a hammer. Viola! Flat as new! You will want to use a stairway so you can let the top inch with the connector hang over the edge. Otherwise when you hit the douser, it will bend at the top.

Just remember to let it cool down for about 10 minutes before you try and reinstall it.

Posted by David Emery (Member # 382) on 09-04-2000, 10:30 PM:

Or you can do like we do. We took out all the Dowser (Changeover Plates). We now start our projectors with the dowser handle. This prociedure works very well and you dont have to worry about the changeover plate falling in the light path ever again or the plate getting warped to the point that you cant get it to open.

Posted by Kevin Crawford (Member # 469) on 09-04-2000, 11:48 PM:

David, do you stand at each machine as the film tails out and close the hand douser? Or do you let the end of the film after the rating band run through?

I much prefer to have the changeover close and not show the tail of the film to who ever is in the auditorium. Of course you could do what I have seen, as an increasing number of people do, and chop off the tail of the film, and put your label on the rating band.

Posted by David Emery (Member # 382) on 09-05-2000, 01:19 AM:

No we just let it run though. If it isn't hard I would love it if the last que could shut off the lamp which would give the same effect as the changeover closing. But we hardly ever have anybody in there at the very end to see the white flash on the screen.

Posted by Kevin Crawford (Member # 469) on 09-05-2000, 02:52 AM:

What type of automation do you have? Xetron's newer automations shut down the lamp.

You may be able to jerry rig a relay setup off of the douser pulse to shut it off.

Brad, I just noticed that you don't have a threading light. Doesn't that make things a little more difficult?

Posted by Brad Miller (Member # 2) on 09-05-2000, 03:35 AM:

It makes things much easier if you remove the framing light during this melting of the douser plate. But to answer your question, no, we don't use them. The way the Christie gate is designed, the framing window can be deceptive. Pulling the framing light forces the operators to frame on the aperture. We never have an out of frame start. An unlit aperture on a Christie is actually easier than framing with a backlit framing window anyway.

Posted by Scott Norwood (Member # 30) on 09-05-2000, 06:09 AM:

Argh! I _hate_ seeing tail leaders run through at the end of a show! That's one of my major pet peeves with too many theatres. It looks tacky in every possible way...

Posted by John Pytlak (Member # 331) on 09-05-2000, 08:23 AM:

I second Scott's opinion. Showing the tail leader on the screen is tacky

-- especially since the people staying for all the credits are usually either film buffs, or folks that actually worked on the movie and want to see their name on the screen! Of course I always stay to see the "Kodak Film" credit at the very end.

------------------
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 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com

Posted by Mark Gulbrandsen (Member # 72) on 09-05-2000, 11:43 AM:

Brad the blacksmith.........are these now to be considered forged dowsers??? If true then the P35 would be the only projector in the world to have forged dowsers wouldn't it?
Mark

Posted by John Pytlak (Member # 331) on 09-05-2000, 12:28 PM:

Sounds like Brad is "forging ahead" and "beating swords into plowshares".

Would there be a way to make the dousers/dowsers (sp?) from a ceramic material that wouldn't warp with the heat?

BTW, are asbestos (e.g., TRANSITE) materials still allowed for specialized applications needing heat resistance?

Posted by Brad Miller (Member # 2) on 09-05-2000, 12:49 PM:

Hmmmm, where's Greg Mueller when you need him. He's got a machine shop and might be able to offer some suggestions on material.

Ideally, it is my opinion Christie (and any manufacturer) should blast their electric dousers for 60 second bursts as a test with the largest lamp they can. I don't think the douser was designed to be able to withstand more than a conventional 7-8 second blocking of the light, which is crazy. Many of us prefer to have lengthy head and tail leaders to protect the film and offer "abort" possibilities during the run down.

Posted by Joseph Pandolfi (Member # 223) on 09-05-2000, 03:11 PM:

We put a cue 18 feet from the end frame of the rating code for our automation to kick in closing the changeover midway thru the rating code. The way ours is set up, when the failsafes drop the lamp and the projector shuts down. We also have a time delay to automaticaly shut it down after 24 seconds in case the tail breaks and the failsafes stay up.