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Author Topic: Westrex Tower Capacity w/36" reels
Lindsay Morris
Expert Film Handler

Posts: 233
From: Darlington, WA, Australia
Registered: Sep 2002


 - posted 10-04-2005 04:52 AM      Profile for Lindsay Morris   Email Lindsay Morris   Send New Private Message       Edit/Delete Post 
Amanda,
Run time on any reel size is easy to calculate.
Use this formula:

Time in Minutes = (D^2-d^2)/ 8.5 for Acetate stock or approx 7.8 for poly stock.
D = The Diam of the reel of film in inches.
d = The Diam of the Hub also in inches.
The 8.5 or 7.8 constant is apparently calculated from how the various films wind in free air with acetate averaging .00625" per layer and the poly stuff obviously less.
The accuracy can be thrown out with super tight winds or sloppy winds.The EPRAD Double MUT is pretty consistent with its winding tension so I have found that what I calculate is quite close to the actual run time thru the machine.
Most of my programs are a mix of acetate and poly so things get a bit rubbery then.

The same formula can be used for feet on the spool by using:
(D^2-d^2) X 10.56 = Feet for acetate stock... dunno about poly here as have not bothered to try and work that out as have had no need.
All my Front of House folk only want to know is program end time they aint the least bit interested in how many feet of film there are.
The EPRAD spools I have are 42" blighters and they all have 8" hubs so d^2 in my case is always 64 and to calc the run time takes all of 10 secs with a small calculator.
Hope this helps.
Lindsay

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Peter Hall
Master Film Handler

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


 - posted 10-04-2005 12:41 PM      Profile for Peter Hall   Author's Homepage   Email Peter Hall   Send New Private Message       Edit/Delete Post 
Pete

Maybe you have the Kinoton / Proecson relationship the wrong way around ? On the towers anyway..

Westrex towers - we have modified a couple (simply spacing the plates out) to take 5000m, i.e. around 3h20m of polyester. Works well, however you should use either an easy spool or a controller on the projector motor..

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Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99


 - posted 10-04-2005 12:44 PM      Profile for Brad Miller   Author's Homepage   Email Brad Miller       Edit/Delete Post 
For general information - the Goldberg platter reels are 38 inches in diameter and have a 14.5 inch hub.

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David Graham Rose
Expert Film Handler

Posts: 187
From: Cambridge, UK
Registered: Sep 2002


 - posted 10-04-2005 02:49 PM      Profile for David Graham Rose   Email David Graham Rose   Send New Private Message       Edit/Delete Post 
Greetings From Cambridge Tower Fanatics

I once modified a Westrex 5035 (obviously with Variacs) by cutting the unit in two and wall mounting the two separate sides. Thus doing I was able to accomodate 63" discs that I had hand made with 6" diameter centres that would run just over 8 hours of film. I was able on one occasion to run 'The Sound of Music' followed by 'Gone With The Wind" with only having to lace up once. There was quite some tension, which I appreciate is not good for film in the last 40 mins of GWTW! I used 10' of white spacing within the programme to alert me to the various intermission points in the vast conglomeration of celluloid!

Yours with fond memories of days gone by I wish you all a Good Night.

David

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Pete Naples
Phenomenal Film Handler

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


 - posted 10-05-2005 04:38 AM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
Peter, not according to Kinoton! However, prove me/them wrong and I will stand corrected.

That's a good point about projector motor run up with these beasts, something I should have mentioned. The original Westrex manual details simple and effective ways of slugging the run up with the popular machines of the era, Westar, DP75, FP20, Kalee 21 etc. The most obvious modern solution is to use a 3 phase drive motor, and a nice inverter. I always advocate the use of EZ start spools on the take up, NOT on the pay off as some operators insist on doing (the screeching noise on rewind is terrifying!)

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Amanda Mundin
Expert Film Handler

Posts: 122
From: Belper, Derbyshire, UK
Registered: Sep 2005


 - posted 10-06-2005 07:04 AM      Profile for Amanda Mundin   Email Amanda Mundin   Send New Private Message       Edit/Delete Post 
Thanks for the help guys.
Just a thought has anyone ever modified a westrex double sided tower to payoff on 1 side and take up on the other, in order to fit potentially much larger spools on?
If not could it be done?

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Leo Enticknap
Film God

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


 - posted 10-06-2005 08:11 AM      Profile for Leo Enticknap   Author's Homepage   Email Leo Enticknap   Send New Private Message       Edit/Delete Post 
The problem there would happen when you tried to rewind, as far as I can see. Assuming you'd be paying out and taking up onto the top spindles (using the bottom ones would foul the base of the unit beyond a certain diameter of spool), you couldn't mount two of the larger spools top and bottom on one side. Therefore you'd need to turn the film round 180° in order to rewind it. Unless I'm missing something, that could only be done safely using rollers when running at a very low speed - too low to be able to rewind a three-hour feature in a typical show turnaround slot.

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Pete Naples
Phenomenal Film Handler

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


 - posted 10-06-2005 10:07 AM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
Never done it, but I see no reason why it couldn't be done.

Leo, remember that the motor plates can be moved up and down on the racking, so you coule raise the lower plates to get bigger spools on. Getting the motors to do different things would be a simple enough job of moving wiring.

The Kinoton/Projecsan single sided tower/pedestal has the spools arranged this way, and rewinds very successfully. Although I should point out that the motors are inverter controlled with tension sensing arms, whereas the Westrex control system is rather more crude.

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Brian Guckian
Jedi Master Film Handler

Posts: 594
From: Dublin, Ireland
Registered: Apr 2003


 - posted 10-06-2005 09:20 PM      Profile for Brian Guckian   Email Brian Guckian   Send New Private Message       Edit/Delete Post 
Pete, that's great advice re. using an EZ hub spool for the take-up. With a proper mylar leader and a (reasonably) gentle motor ramp-up you can't go wrong.

BUT...in this day and age of H&S is it really wise to be (a) still using towers, and (b) trying to get even bigger spools on?

Who's doing the lifting? Or is it the case that everything's made up on the tower (lower spool) then rewound to the top?

Making up on the tower - even from 6000ft spools done on a bench first - has never been ideal to me, but I've never done enough of it.

I'll put up a separate thread asking people what they consider is best practice in towers today!

(BTW a former colleague worked in London many years ago and told me that when towers first came out some boxes had block and tackle to safely move the reels around...was this part of the original Westrex spec?)

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Leo Enticknap
Film God

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


 - posted 10-07-2005 03:06 AM      Profile for Leo Enticknap   Author's Homepage   Email Leo Enticknap   Send New Private Message       Edit/Delete Post 
In the early '90s I had a part time job in one of the south coast fleapits. It had been twinned in such a way that screen 2's booth was little bigger than a 'phone box (it was a jerrybuilt shack on the roof - which, it later transpired, had been put up without planning permission), with the result that prints had to be made up onto tower spools in the other booth and manhandled up a 72-step spiral staircase. I remember the 72 steps, because the only way to hold the spool in such a way that it would fit in the stairwell obscured your view of the way ahead, meaning that counting the steps was the only way to know when you'd reached the top or bottom.

After a month of suffering an almost constant backache, I suggested to the chief/manager/owner that we buy a couple of 6k spools to move prints up and down that staircase on, in order to reduce the risk of an accident. He had the personality of Basil Fawlty, but expressed himself using language that wouldn't normally be heard on the BBC. His response was to dismiss the idea, call me a 'fookin' student poofter' and sack me on the spot.

A few weeks later he fell down those stairs while moving a print of Speed, broke both arms, several ribs, a wrist and a shoulder blade. While he was in hospital, the council's health & safety police moved in and uncovered a catalogue of deathtraps throughout the building, the extent of which made you wonder how any of the staff and customers ever came out of that place alive. The theatre was closed for several months, and eventually changed hands.

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Stephen Furley
Film God

Posts: 3059
From: Coulsdon, Croydon, England
Registered: May 2002


 - posted 10-07-2005 07:09 AM      Profile for Stephen Furley   Email Stephen Furley   Send New Private Message       Edit/Delete Post 
quote: Brian Guckian
BUT...in this day and age of H&S is it really wise to be (a) still using towers, and (b) trying to get even bigger spools on?
(a) I don't see why not.

(b) Probably not.

I've only run towers a few times; I find that a typical print isn't too bad to lift, but I wouldn't want to go much heavier. I would probably get help for a print of much over two hours. It is now the rule in some cinemas that prints over a certain length must be lifted onto the tower by two people.

quote: Brian Guckian

(BTW a former colleague worked in London many years ago and told me that when towers first came out some boxes had block and tackle to safely move the reels around...was this part of the original Westrex spec?)

I remember reading somewhere that lifting equipment was provided for the original Cinerama installations, I'm not sure if this applied to all of them, but I think the Cinerama spools were only about 8-9k, considerably smaller than tower spools.

I have seen a couple of towers which were made to be able to take 70mm spools, though I've never seen such a spool, and I certainly wouldn't want to lift a full one.

Most tower spools are made of aluminium, and are quite light, lighter than many older designs of 6k spools, so a print on a tower spool isn't much heavier than one on a platter ring; and is probably easier to lift; I wouldn't want to carry one up, or even worse down, a staircase though.

quote: David Graham Rose
I once modified a Westrex 5035 (obviously with Variacs) by cutting the unit in two and wall mounting the two separate sides. Thus doing I was able to accomodate 63" discs that I had hand made with 6" diameter centres that would run just over 8 hours of film.
I can't understand why anyone would want to run that amount of film on one spool. You wouldn't run a programme that long without an intermission, probably more than one, and if you have an intermission then why not just change smaller spools? I would have thought that the core to full spool diameter ratio of 10.5:1 would be likely to cause problems too.

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Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12814
From: Annapolis, MD
Registered: Dec 1999


 - posted 10-07-2005 08:16 AM      Profile for Steve Guttag   Email Steve Guttag   Send New Private Message       Edit/Delete Post 
I think Kinoton's SPT5000K is an elegant machine for what it is. It has BOTH reels (40", if I'm not mistaken) just about an inch off the ground. The electronics are such that floating hubs are not as needed as with other systems.

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Robert Throop
Master Film Handler

Posts: 412
From: Vernon, NY USA
Registered: Jun 99


 - posted 10-07-2005 08:55 AM      Profile for Robert Throop   Email Robert Throop   Send New Private Message       Edit/Delete Post 
[/QUOTE]I remember reading somewhere that lifting equipment was provided for the original Cinerama installations, I'm not sure if this applied to all of them, but I think the Cinerama spools were only about 8-9k, considerably smaller than tower spools.[/QUOTE]
The reel elevators were added for HTWWW as one of the acts was over 11000 ft.
Bob

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Mark Hajducki
Jedi Master Film Handler

Posts: 500
From: Edinburgh, UK
Registered: May 2003


 - posted 10-07-2005 09:02 AM      Profile for Mark Hajducki   Email Mark Hajducki   Send New Private Message       Edit/Delete Post 
quote: Leo Enticknap
that we buy a couple of 6k spools to move prints up and down
I thought virtually every tower using cinema made up the films onto 6k spools and only made the one splice on the tower.

I have heard of people hand winding onto 13ks using a modified winding bench, but that is not recomended.

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Pete Naples
Phenomenal Film Handler

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


 - posted 10-07-2005 09:35 AM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
Yeah, make up on 6k's, join on the tower, break down with asplit spool on the top of the tower after the last run.

If you make up from cans, on the tower, you can't be checking the print properly, end of story!

The Dominion in Edinburgh has a modified bench that will take 13,000 foot spools, personally I hate it, but then their Cinemecannica towers aren't the friendlies of things when trying to use smaller spools on. There is NO adjustment for wind speed or tension.

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