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Topic: Help with timing a barrel shutter

Don Furr
Jedi Master Film Handler

Posts: 509
From: Sun City, Ca USA
Registered: Nov 2002

posted 11-07-2002 10:07 PM

Can anyone tell me what the correct position of a barrel shutter should be when a framing line is pulled down to the middle of the framing window? I'm trying to time a DeVry XD.
Thanks

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Josh Jones
Redhat

Posts: 1207
From: Plano, TX
Registered: Apr 2000

posted 11-08-2002 12:15 AM

Done this many a time

The blade should be centered in the aperture when the frame line is as well. you may have to adjust this slightly, as the slop in the drive train will cause a difference in adjustment.

Josh

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Leo Enticknap
Film God

Posts: 7474
From: Loma Linda, CA
Registered: Jul 2000

posted 11-08-2002 03:18 AM

I once had to do this on a GK-37 and applied that theory. But the job turned out to be seriously fiddly and within a couple of hours I was screaming abuse at the thing. Those mechs are

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Peter Hall
Master Film Handler

Posts: 314
From: London, UK
Registered: Dec 2000

posted 11-08-2002 10:38 AM

Do NOT slagg off Kalee ! Oil bath, dead silent and a total virtue to their design that there are plenty of them still running 40 years after they stopped being made. Plus the drum shutter supposedly is more efficient than blades. OK, they piss out oil and the aperture is a pain (wasn't pre 1952, when they were designed, or pre platter, when they had their heyday) but coming from New Zealand I know and love them. If w(p) = q(p), w being weight and q being quality (P is projector) then the Kalee is a close third to the DP70 and the mightly Ernemann 7.8.9.10 range.

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Ken McFall
Jedi Master Film Handler

Posts: 615
From: Haringey, London.
Registered: Apr 2001

posted 11-08-2002 06:35 PM

The old 'BRAT', bottom retard, top advance does not apply in the usual way as light can in fact pass over the top of one blade and under the bottom of the other....

The film should not start to move until both blades of the drum are vertical. I can't remember which way the drum rotates. If we assume its clock wise the top of the cone of light can pass over the top of the rising blade and under the falling blade and visa versa. So it is important to ensure the film does not move until the blades are vertical to each other giving maxium cut off. I seem to recall you timed looking at the blade nearest to the film gate.

Sorry if this explanation isn't very clear.... it's been a long time.

Its not enough to time them so that the middle line is covered as the top or bottom of the light cone could pass thru the top or bottom of each side of the drum.

The problem with drum shutters from what I recall is that the depth of the actual shutter drum required a narrower cone of light than the flat type of blade other wise there was a serious loss of light!

The contra rotating twin shutter that was avaiable for the Westar was much easier to setup and gave the same effect as a drum shutter.

This is all from memory of a long long time ago so excuse the accuracy.

Have to say I loved the Kalee range, 19 with president arc, and projectomatic model 'O' was a fairly typical install in many army cinemas in the UK. They were very reliable and as Peter says they were, are, quality machines.

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Luciano Brigite
Master Film Handler

Posts: 277
From: Sao Paulo, SP, Brazil
Registered: Jan 2002

posted 11-08-2002 08:12 PM

Josh is right about how to time the shutter.
I have a pair of Kalee's model 12 and they have barrel shutters.
had to re-time them after a good cleaning before putting them back to work. also did the same with a few Erneman's most of them, the model 4. frame line in the centre of apperture, both blades closing the light passage. make sure you have the centre of each blade aligned with the frame line.

And.. the kalee's are good stuff.

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Bob Koch
Expert Film Handler

Posts: 183
From: williams ca
Registered: Nov 2001

posted 11-08-2002 11:56 PM

As always; inch the proj with handwheel or whatever and advance 2 intermittent sprocket teeth. Assuming you have loosened the barrel shutter previously, hold the mechanism firm where you have advanced it 2 teeth and rotate the barrel to a horizonal position ie it completely blocks the light beam. This always worked with Motiograph from the Model F, K, Hu,,and up to the AA. A Devry is something I would prefer not to remember.

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