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Author Topic: Elmo GS1200 Xenon Fan problem
Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003


 - posted January 07, 2007 08:41 AM      Profile for Kevin Faulkner         Edit/Delete Post 
Bill, I too would like to read those bulletins if you manage to find them. It would be interesting to see what Elmo had to say about this.

When you consider people like Keith Wilton who has used his Early machine for years I wonder if there really is any advantage to the extra forced cooling.

Kev.

--------------------
GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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David Pannell
Phenomenal Film Handler

Posts: 1072
From: Horsham, West Sussex, UK
Registered: Nov 2004


 - posted January 07, 2007 09:26 AM      Profile for David Pannell   Author's Homepage     Send New Private Message       Edit/Delete Post 
Ouch!! [Eek!]

That fan looks pretty horrendous. I am sure one would need to be extremely careful not to upset the balance when repairing one of these. Otherwise it would knock the fan motor bearings out in very short order, to say nothing of an annoying out-of-balance vibration!

Still, I expect you've got all that covered, Kev! [Cool]

--------------------
Dave.

Valves and celluloid - a great combination!
Early technology rules OK!

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003


 - posted January 07, 2007 10:06 AM      Profile for Kevin Faulkner         Edit/Delete Post 
David,

Clive has now repaired it and did use some wire round the middle. He has now run the machine again and all seemed ok.
My only concern is that it may go again and wonder of the reduced voltage to the fan would help give less stress. I dont think there is an issue with the cooling really with the lower voltage as Bill says even the early machines seem to be ok where cooling is concerned. Maybe it would be an issue if the machines were used for very long periods of time with not much downtime between shows but for most of us that wouldn't be an issue.

--------------------
GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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David Pannell
Phenomenal Film Handler

Posts: 1072
From: Horsham, West Sussex, UK
Registered: Nov 2004


 - posted January 07, 2007 10:48 AM      Profile for David Pannell   Author's Homepage     Send New Private Message       Edit/Delete Post 
I think I tend to agree with you, Kevin.

I should like to know the original voltage rating of the fan motor, and the percent voltage increase, before passing judgement, however.

If the motor were to be over-volted, it would run hotter itself and have a shorter life. Heat is the killer of all electrical insulation - but I'm sure you know that. It is a very interesting situation if indeed Elmo did increase the supply to the fan motor. Is it in fact the same motor, or did Elmo change the motor to a higher speed one requiring a different voltage? I find it difficult to believe that any company would simply increase the volts just to make a motor run faster - very bad practice and poor electrical knowledge!

How say you?

--------------------
Dave.

Valves and celluloid - a great combination!
Early technology rules OK!

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003


 - posted January 07, 2007 10:55 AM      Profile for Kevin Faulkner         Edit/Delete Post 
Yes that would certainly be a worry but you will probably find that the original was being under run. Never the less the motor would produce more heat [Frown] and that could as you say be a killer.

Kev.

--------------------
GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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Bill Parsons
Film Handler

Posts: 66
From: Brookland. UK
Registered: Jul 2004


 - posted January 07, 2007 11:09 AM      Profile for Bill Parsons   Email Bill Parsons   Send New Private Message       Edit/Delete Post 
Dimitrious, no my final word is not to leave the transformer in, it’s worth trying with the lower voltage it comes off the 30v rail, it usually runs at about 32v I think, it’s just that the lamps don’t come cheap!
David, the voltage was increased to about 40v going on memory the motors were rated at 50v, Elmo usually used well rated motors, the main drive motor as you know works on a voltage increase to run between 18 & 24fps, I have never seen a faulty fan motor due to extra voltage, just the fans.

Bill

[ January 08, 2007, 07:21 AM: Message edited by: Bill Parsons ]

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David Pannell
Phenomenal Film Handler

Posts: 1072
From: Horsham, West Sussex, UK
Registered: Nov 2004


 - posted January 07, 2007 11:12 AM      Profile for David Pannell   Author's Homepage     Send New Private Message       Edit/Delete Post 
Are we saying that the transformer now supplies the motor with the correct operating voltage? If so, then clearly that's OK, but it does seem a bit strange that the motor was underrun in the first place - why???

I'd be very interested if the technical bulletin becomes available. It's just a bit difficult to understand their philosophy if this is the case.

I want to talk to their design engineer!!! [Big Grin]

--------------------
Dave.

Valves and celluloid - a great combination!
Early technology rules OK!

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Bill Parsons
Film Handler

Posts: 66
From: Brookland. UK
Registered: Jul 2004


 - posted January 07, 2007 01:16 PM      Profile for Bill Parsons   Email Bill Parsons   Send New Private Message       Edit/Delete Post 

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003


 - posted January 07, 2007 01:21 PM      Profile for Kevin Faulkner         Edit/Delete Post 
Wouldn't we all. We would then get then to design the final GS with all the things we want and guides which don't wear.

Bill, With them increasing the running speed of the motor does it not effect the the drive to the flywheel ie it could get to fast?

I think that it might just be worth dropping the voltage back to the normal 29V tapping on the main transformer which might just take a bit more stress of the fan blades.

Another thought Bill is that the blades on my Xenon look more like a polythene plastic as its very shiny but on the GS std I have stripped down at present the plastic looks different. It's very dull in it's finish.

I wonder if that blade of Clive's just split like that nylon type plastic is prone to.

Anyway at least he's now got it back together and working.

Kev.

--------------------
GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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Graham Sinden
Phenomenal Film Handler

Posts: 1131
From: Kent, UK
Registered: Aug 2005


 - posted January 07, 2007 01:22 PM      Profile for Graham Sinden   Email Graham Sinden   Send New Private Message       Edit/Delete Post 
It would be a nice idea if any Technical Bullitins from any maker (e.g. Eumig, Elmo etc.) could be scanned and placed in the Manuals section of the forum.

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Bill Parsons
Film Handler

Posts: 66
From: Brookland. UK
Registered: Jul 2004


 - posted January 07, 2007 01:30 PM      Profile for Bill Parsons   Email Bill Parsons   Send New Private Message       Edit/Delete Post 
Kevin, yes as you say the flywheel does run faster in the idle mode, but this does not appear to cause any problems, you could have a point with the type of plastic that the fans are made of, the correct material should not break.
Bill.

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David Pannell
Phenomenal Film Handler

Posts: 1072
From: Horsham, West Sussex, UK
Registered: Nov 2004


 - posted January 08, 2007 05:38 AM      Profile for David Pannell   Author's Homepage     Send New Private Message       Edit/Delete Post 
Thanks for your explanation of the motor rating, Bill. Makes sense - up to a point. [Wink]

--------------------
Dave.

Valves and celluloid - a great combination!
Early technology rules OK!

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Clive Carmock
Film Handler

Posts: 69
From: London, UK
Registered: Feb 2005


 - posted January 08, 2007 03:28 PM      Profile for Clive Carmock   Email Clive Carmock   Send New Private Message       Edit/Delete Post 
As Kevin mentioned I have managed to get the fan glued back together again.

It was still held fasdt to the spindle even in that 'open' state. I used a couple of bands if wire around the edge and twisted that to tighten it up to close the gap.

As Kev suggested I put some araldite on the top surface of the fan across the crack to provide extra support. I did use a small blade to 'rough' the surface a little to give the glue a better surface to key into. And of course cleaned the plastic with alcohol to de-grease it first.

The araldite has set hard and is holding the fan togetehr very well.

I did wonder about vibration, but can't detect any when the fan runs.

My GS 1200 is like the one Ugo is repairing, with the transformer mounted close to the flywheel.

In a while I will measure the voltage across the running fan motor and post my findings here.

I would desrcibe the fan noise from this machine rather like a Jet engine, and much louder than my Standard GS1200 (which is a Mk1 version)

So far I have run a few shorts since repairing the machine and it's holding it's own so far.

Regards
Clive

Edited - just measured the voltage on the fan motor - 44.6V

[ January 08, 2007, 04:36 PM: Message edited by: Clive Carmock ]

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003


 - posted January 09, 2007 01:30 AM      Profile for Kevin Faulkner         Edit/Delete Post 
On my Xenon without the extra transformer the voltage is about 33Volts DC. At that voltage mine is loud enough so I can imagine what its like at 45V!

Kev.

--------------------
GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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Ugo Grassi
Jedi Master Film Handler

Posts: 506
From: Avellino (Italy)
Registered: Dec 2003


 - posted January 09, 2007 01:27 PM      Profile for Ugo Grassi   Email Ugo Grassi   Send New Private Message       Edit/Delete Post 
On the little transformer there is the output value: 6,3 volt. So I assume when the fan is working the whole vultage is less 39 v.

--------------------
Bye
Ugo

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Alan Rik
Film God

Posts: 2211
From: New York City, NY, USA
Registered: Jun 2003


 - posted January 09, 2007 02:48 PM      Profile for Alan Rik   Email Alan Rik   Send New Private Message       Edit/Delete Post 
I had 3 Xenon machines and to my ears they all sounded like a mini jet taking off compared to a regular Halogen GS.

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003


 - posted January 09, 2007 06:18 PM      Profile for Kevin Faulkner         Edit/Delete Post 
I have to say that I am considering modifying my machine so that when the lamp is not struck it throttles back to a lower speed. Something like the std GS does but maybe with some delay to give the lamp time to cool down.

I find the noise a real pain when the machine is in idle mode.

--------------------
GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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Lars Pettersson
Master Film Handler

Posts: 282
From: Stockholm, Sweden
Registered: Jan 2007


 - posted March 26, 2007 01:53 PM      Profile for Lars Pettersson   Email Lars Pettersson   Send New Private Message       Edit/Delete Post 
Hello everyone!

This is probably a bit "old hat" but as I posted in the buy/sell Forum, I have plenty of ELMO spares, mostly for the ST series. I think there are something like 20-30 fans in there. None with cupped blades though.

Best Wishes
Lars

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Clive Carmock
Film Handler

Posts: 69
From: London, UK
Registered: Feb 2005


 - posted June 09, 2012 04:32 PM      Profile for Clive Carmock   Email Clive Carmock   Send New Private Message       Edit/Delete Post 
Sorry to ressurect an old thread, but my GS1200 Xenon is sick again. I am suspecting the fan again. I was settling down to watching an Optical feature this evening of Rising Damp to replace my 16mm copy that has turned totally red.

About 600 ft into the first 1200ft reel the machine started to make a screeching noise. I immediately shut it off.

I find that with the power on, but the mechanism not running the screeching noise is there.

So I am suspecting the fan unit again - either my old repair on the fan blade unit has failed and it is rubbing against somethign again, or the fan motor bearign have gone.

I need to spend soem time stripping it down again, but wondered if anyone knew of a source of spare fan motors or fan blades?

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Clive Carmock
Film Handler

Posts: 69
From: London, UK
Registered: Feb 2005


 - posted June 17, 2012 12:39 PM      Profile for Clive Carmock   Email Clive Carmock   Send New Private Message       Edit/Delete Post 
Following on from my post. I have now removed the fan and fan motor from the projector. The fan motor itself seems fine - it wasn't turning quite as freely as you'd expect but a few drops of light oil on the bearings either end fixed that and now it rotates very freely.

However the plastic fan blade unit is at fault again. I think the heat from the machine over time has softened the epoxy resin glue I used and the crack opened up a little more. I see the beginnings of a second crack at 90 degrees to the first one now. So I suspect this particular fan blade will be of no use.

The good news is that I doubt whether I will need a new fan motor, but will need a new fan blade unit for it. If anyoen knows of a supply of them, or alternatively of a scrap machine being used for spares I'd be interested in buying the fan from it.

Did the GS1200 share fan assemblies with any of the other Elmo machines? If so I can keep a look out for those as well.

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