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Author Topic: Westrex 2001 strange shutter ghost problem
Matthew Taylor
Expert Film Handler

Posts: 186
From: Essex, UK
Registered: Mar 2004


 - posted 10-20-2006 04:44 PM      Profile for Matthew Taylor   Email Matthew Taylor   Send New Private Message       Edit/Delete Post 
I have a friend who runs a small cinema and uses an old Westrex 2001 projector. He is having a problem with some wierd ghosting that cannot be adjust out using the timing knob. It appears at towards the top AND bottom of the screen. The ghosting goes in a downwards direction at the top and upwards at bottom with no apparent ghosting in the middle.I suggested he paint the shutter blade because it was bare metal but this has made no difference.

Any ideas anyone?

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Rick Raskin
Phenomenal Film Handler

Posts: 1100
From: Manassas Virginia
Registered: Jan 2003


 - posted 10-20-2006 04:58 PM      Profile for Rick Raskin   Email Rick Raskin   Send New Private Message       Edit/Delete Post 
Is the machine a double shutter mechanism? If so then I suspect the shutters need to be re-timed.

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Matthew Taylor
Expert Film Handler

Posts: 186
From: Essex, UK
Registered: Mar 2004


 - posted 10-20-2006 05:04 PM      Profile for Matthew Taylor   Email Matthew Taylor   Send New Private Message       Edit/Delete Post 
I am not sure. Is a double shutter usual for these machines?

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Pete Naples
Phenomenal Film Handler

Posts: 1565
From: Dunfermline, Scotland
Registered: Feb 2001


 - posted 10-20-2006 05:24 PM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
Did someone mention Westrex [Smile]

Double shutter was rare, not unheard of but rare.

Now there are a couple of things that spring to mind.

One, the sliding gear on the vertical shaft, if it's worn on it's keyways, then you get ghosting, similarly if the entire gear train is sloppy you'll get ghosting.

Two, the shutter needs to be sited on the shutter shaft as near to the aperture as possible.

Three, hole in the shutter blade? You'd be amazed at the number I've found with holes burned in them, or with the blades badly warped.

Four, the Westrex blade was very tight, so as to maximise light output. Now with todays efficient lenses and xenon lamps, often we find that we can go to a wider shutter blade. IIRC the standard Westrex blade was 90º, I usually fit a 100º blade on memory, or the adjustable type.

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Richard May
Phenomenal Film Handler

Posts: 1057
From: Floral Park, NY USA
Registered: Aug 2004


 - posted 10-20-2006 06:43 PM      Profile for Richard May   Email Richard May   Send New Private Message       Edit/Delete Post 
Like Pete said. Sounds most likely to be the sliding gear on the vertical shaft. Whenever I see ghosting up and down, its usually that gear.

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Sam D. Chavez
Film God

Posts: 2153
From: Martinez, CA USA
Registered: Aug 2003


 - posted 10-20-2006 08:12 PM      Profile for Sam D. Chavez   Author's Homepage     Send New Private Message       Edit/Delete Post 
I've seen this when Century's are coupled with fast mirrors of earlier xenon lamps. The cone of light is wider than the projectors were designed to deal with so the light goeas around the edge and end of the blade.

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Ken McFall
Jedi Master Film Handler

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


 - posted 10-20-2006 08:43 PM      Profile for Ken McFall   Email Ken McFall   Send New Private Message       Edit/Delete Post 
Shutter timing would normally result in a ghost at the top OR the bottom not both. So clearly the problem is not simply a timing issue.

You can take everything Pete say's as gosple as he has a lot lot of experience in Westrex projectors. Scotland possibly had, or still has, the most Westrex installs running.

You don't say if this is a new problem, equipment running fine until recently, or a 'new' install that has an unexpected problem.

More information on the type of lamphouse and if it's a single or double shutter mech would help.

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Demetris Thoupis
Phenomenal Film Handler

Posts: 1240
From: Aradippou, Larnaca, Cyprus
Registered: Apr 2001


 - posted 10-21-2006 01:40 AM      Profile for Demetris Thoupis   Email Demetris Thoupis   Send New Private Message       Edit/Delete Post 
Something silly. Is is possible that he has a cracked lens!?
D

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Pete Naples
Phenomenal Film Handler

Posts: 1565
From: Dunfermline, Scotland
Registered: Feb 2001


 - posted 10-21-2006 04:50 AM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
Sam, that's exactly why I fit the wider shutter blade on them. It's usually older machines that suffer from this. Some of the late ones from the dawn of xenon came from the factory with a wider blade.

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Matthew Taylor
Expert Film Handler

Posts: 186
From: Essex, UK
Registered: Mar 2004


 - posted 10-21-2006 05:31 AM      Profile for Matthew Taylor   Email Matthew Taylor   Send New Private Message       Edit/Delete Post 
Thanks for all your input on this. I will hopefully get a chance to see exactly what gear he is using and give some more detailed info this weekend. You've certainly given us a few things to go on.

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Louis Bornwasser
Film God

Posts: 4441
From: prospect ky usa
Registered: Mar 2005


 - posted 10-21-2006 08:15 AM      Profile for Louis Bornwasser   Author's Homepage   Email Louis Bornwasser   Send New Private Message       Edit/Delete Post 
FYI: Westrex 2001 and Century "C" are virtually the same machine. In fact I routinely use old Westrex intermittents in C overhauls.

This is the classic case of "shutter oscillation." Follow all instructions above. If not yet successful, change the shutter bearings and, in the case of Westrex, assure that final alignment includes assuring that the bearings are "in line," Only on westrex there is an eccntric adjustment in the forward shutter bearing assembly.

I make a new style shutter assembly which guarantees precise alignment of the bearings for old Centurys and I could check a westrex casting I have for you, BUT check everything else above first.

BTW: it is not necessary to go over 90 degrees on the blade. In fact, it may be possible to go back to the 83 degree blade. Louis

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Matthew Taylor
Expert Film Handler

Posts: 186
From: Essex, UK
Registered: Mar 2004


 - posted 10-22-2006 11:24 AM      Profile for Matthew Taylor   Email Matthew Taylor   Send New Private Message       Edit/Delete Post 
Just an update on this - I conveyed the information to my friend and he adjusted the shutter to sit closer to the aperture and this has made the ghosting almost negligable now. I recommended that he also paint the inside of the shutter housing and the blade matt black to reduce this even further. There still may be some slack on the gearing as well, he hasn't checked this yet.

Many thanks for your good advice [thumbsup]

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Pete Naples
Phenomenal Film Handler

Posts: 1565
From: Dunfermline, Scotland
Registered: Feb 2001


 - posted 10-25-2006 08:30 AM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
Glad to be of service.

BTW painting the shutter and it's housing black, in my experience won't make any noticeable difference, it's transmitted, not reflected light that's causing the ghosting.

How did your friend get on with gear train/keyway wear? ideally there shold be no rotational play in the sliding gear keyway, any more than half a pubic hair spells trouble. The correct settings for the backlash in the rest of the gear train can be found in the manual, which I think is in the downloads section of this site. If it's not pm me and I'll email you it.

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Matthew Taylor
Expert Film Handler

Posts: 186
From: Essex, UK
Registered: Mar 2004


 - posted 10-25-2006 03:40 PM      Profile for Matthew Taylor   Email Matthew Taylor   Send New Private Message       Edit/Delete Post 
Hi Peter,

He isn't really very technical and although I explained how to check the play in the gear train and vertical shaft he said he wanted me to come over and do it - so far, I've not had time. I will however go there with my ISO-certified pubic hair measure and check [Big Grin]

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