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Author
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Topic: UPGRADING MY ELMO E-80
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David Pannell
Phenomenal Film Handler
Posts: 1072
From: Horsham, West Sussex, UK
Registered: Nov 2004
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posted March 07, 2008 07:03 AM
I love all my projectors, each for some unique aspect which it possesses. Somehow, though, the E-80 holds a special place in my affections. Very simple, unbelievably quiet - almost silent in operation, that 750 watt lamp, the room/table lamp dimmer, and the solid and heavy yet small size, all go to make up a superb standard 8 silent machine. Added to which it is absolutely like new with hardly any miles on the clock at all!
I thought I had an almost equal attachment to the later F-80, witness my review of this machine in the film collectors magazine (FFTC) but recently it has become much more noisy in operation, and my closing words of that review are coming home to roost.
It is a later version of the E-80, and of much more heavy and solid construction, with much to recommend it, but I seriously now wonder if any of the components are of inferior material. I say this because I am now detecting gear and bearing wear, along with a high pitched squeaky whistle which simply won't go away - even with my superior maintenance techniques!!!
Having recently acquired a spare E-80 from our redoubtable "Mr Elmo", I decided to upgrade my E-80 to accept larger reels than the usual 400 footers associated with standard 8 projectors.
I should say that I probably have more standard 8 sound and silent features (as well as home movies) than anything else, which usually run to 4 or 6 x 400 ft reels each.
I have already converted my Eumig Mark S standard 8 sound machine to accept 600 ft reels, simply by installing a spare front arm on the rear as a longer take-up arm. Perfect.
Converting the E-80 was a bit more involved, but I achieved it by customising both reel arms from the F-80.
Firstly, I fitted the longer take-up arm of the E-80 to the top of the projector to act as the feed arm. Easy.
Next task was to join both of the F-80 arms together in such a way as to maintain strength, whilst at the same time trying to keep the whole as professional and as original looking as possible.
The F-80 arms are both of a heavier casting than the E-80, though of very similar appearance, but with a larger web area from which the bearing housing for the spindles is cast. This meant that I could machine a trunion at the end of the longer arm, into which the collar of the shorter arm would fit, as though it were the same as on the body of the projector.
This done, the collar of the smaller arm was drilled out to 0.25in. diameter, and an 0BA nickel plated bolt passed through with a spring washer and nut to secure and adjust friction as per the original arrangement.
The spring wire drive belts were lengthened appropriately with spares, and - voila!
Now, the E-80 can accommodate 800 ft reels, and simply by changing the new take-up arm assembly from the E-80 to the F-80, which now has the longer E-80 arm from the spare E-80 as the feed arm too, (should I wish to), both projectors can use 800 ft reels.
"Too much strain on the motor"?......I hear you ask. Not at all. Remember that the reel drives on these older machines are driven by an external spring wire belt which is designed to slip on the pulleys even with the smallest of reels. A lot to be said for older technology!
I am now in the throes of re-spooling my sound and silent films onto 600 and 800 ft reels. Then I can enjoy a feature without having to jump up half a dozen times to change the reel.
EXCELLENT!
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Dave.
Valves and celluloid - a great combination!
Early technology rules OK!
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David Pannell
Phenomenal Film Handler
Posts: 1072
From: Horsham, West Sussex, UK
Registered: Nov 2004
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posted March 07, 2008 08:15 AM
I'll try to do so over the weekend if poss.
BTW, I forgot to mention that part of the upgrade was to install a new and better lens.
The stock lens is a 20mm f1.4.
I was recently given a German made Schacht Travenon 20mm f1.3 with the same 22mm diameter barrel. This lens has a conical flared hood which cuts down tremendously on light scatter, and is of course a faster and brighter lens. Not by a vast amount, but nevertheless still makes quite a difference and well worth having! Also, the helix is much finer than the stock lens, so focussing is ultra precise.
Decided to edit my post and add the pictures now. All photos taken in the workshop, as I've only just finished the project, and couldn't wait to tell everyone:
(Below) General view of the modified Elmo E-80, showing an 800 foot reel on the bottom arm! Note the longer original lower arm now fitted to the top!
(Below) This is the new f1.3 hooded lens.
(Below) The F-80 modified arms.
(Below) Machined trunnion at the lower end of the longer F-80 arm. This trunion is all that remains of the original bearing casting which was identical to the bearing casting you now see on the shorter arm! The shorter F-80 arm is unmodified apart from the hole in the collar being drilled out to 0.25in. diameter. Note how meaty these arms are, compared with the E-80 arms!
I know the colour of the arms is a bit different, but I intend to rectify that in the fullness of time. It was more important to get the engineering right!
Obviously, it was also necessary to swap the pulleys over, so that the smaller one is on the feed spindle, and the larger one is on the take-up spindle.
[ March 08, 2008, 06:05 AM: Message edited by: David Pannell ]
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Dave.
Valves and celluloid - a great combination!
Early technology rules OK!
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David Pannell
Phenomenal Film Handler
Posts: 1072
From: Horsham, West Sussex, UK
Registered: Nov 2004
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posted March 07, 2008 01:35 PM
What a Friday this has been!
I decided NOT to be beaten by the seeming problems with the F-80, so proceded with a strip-down late this afternoon.
I carefully examined each component in the drive train under a laboratory type illuminated magnifying glass (you know the sort, on an Anglepoise type stand) but could find nothing actually wrong - until I came to the motor itself.
Not bearings, but commutator and brushes!
When I first acquired this projector, I carried out all my usual and detailed maintenance procedures, including the motor. The commutator and brushes were in good shape at that time. However, the brushes were now quite worn and also the commutator was now scored. How ![[Confused]](confused.gif) Why
I have just skimmed and polished the commutator on the lathe and inspected the brushes with additional illuminated magnification. What I discovered was that there was a particularly hard piece of carbon graphite on the face of one of the brushes, which had scored the commutator and was causing the high pitch squeal.
This is the first time I have encountered this phenomena. Clearly the carbon used in the manufacture of the brush was not sufficiently refined, and had small grains embedded which were very hard.
Having now fitted a new set of brushes, dressed to the correct size and shape from a piece of high quality carbon brush material, all I can now hear from the F-80 is the sound from the extremely efficient blower! This blower moves nearly twice as much air as the E-80 as it is much bigger with many more vanes. Being a larger diameter, the peripheral speed is far greater than the E-80, about twice, according to the calcs, therefore moving proportionally more air in a given period of time. This is why this lamphouse stays quite cool campared with others, even with the designed 750 watt lamp; and why the air blast is louder and actually tends to blow your hand away from above the lamphouse vents.
SO; I've now got my F-80 back again! ![[Big Grin]](biggrin.gif)
NEXT PROJECT?
Having previously tried out a 1,000 watt lamp in this projector with no detrimental effects, subjectively speaking, the next phase is to repeat the tests objectively with comparative temperature readings using an electronic thermometer. The air blast is so bl...y vicious, and the lamphouse so bl...y large, that it should work - - - - - - - - .
I'll publish the results!
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Dave.
Valves and celluloid - a great combination!
Early technology rules OK!
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David Pannell
Phenomenal Film Handler
Posts: 1072
From: Horsham, West Sussex, UK
Registered: Nov 2004
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posted March 08, 2008 07:08 AM
quote:
SO; I've now got my F-80 back again!
NEXT PROJECT?
Having previously tried out a 1,000 watt lamp in this projector with no detrimental effects, subjectively speaking, the next phase is to repeat the tests objectively with comparative temperature readings using an electronic thermometer. The air blast is so bl...y vicious, and the lamphouse so bl...y large, that it should work - - - - - - - - .
I'll publish the results!
Got everything set up ready to take some actual temperature measurements to compare the E-80 with its 750 watt lamp, and the F-80 with a 1,000 watt lamp.
As can be seen by the above quote from my earlier post, there was no subjective evidence of any bad effects with the 1,000 watt lamp in the F-80. But that experiment was only for a few minutes.
However, I decided to take the measurements every 15 minutes to see what kind of difference in lamphouse temperature there would be between the 2 projectors.
I'll stop here!!!
After the first 15 minutes, the F-80 lamphouse was too hot to go near - let alone touch, so the scientific test was abandoned there and then; without even bothering to take any temperature measurements.
Conclusion:
Although the F-80 certainly does have a bigger blower creating a stronger air blast up through the larger lamphouse, clearly it is not sufficient to acommodate an additional 250 watts of lamp. It is just a bit more efficient than the E-80 blower, but there has never been any trouble with E-80 using the maximum recommended 750 watt lamp. Same now goes for the F-80. 750 watts it is!!
Once again we discover that it isn't wise to fit a larger wattage lamp than the maximum recommended, - no matter what any evidence or thoughts to the contrary might be!!
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Dave.
Valves and celluloid - a great combination!
Early technology rules OK!
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