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Author Topic: Simplex guru's: please help
Frank Angel
Film God

Posts: 5305
From: Brooklyn NY USA
Registered: Dec 1999


 - posted 04-28-2002 10:02 AM      Profile for Frank Angel   Author's Homepage   Email Frank Angel   Send New Private Message       Edit/Delete Post 
We have a Simplex soundhead from the Simplex 35 series after Strong/Ballentine manufactured them. The older models that I have in the big theatre have felt around this pressure roller, not rubber. This is the roller that sends Brad into spasms.

Yesterday in the middle of SW Ep 1, the sound begins to warble. A quick check reveals that pieces of the rubber pressure roller had actually broken off the roller assembly (the roller that presses the film against the sound drum). Leaving a gap and a very knarly looking metal substrata that evidently the rubber is formed around.
Amazingly enough I found four of these parts in a rather spare parts box, which leads me to believe that they must fail quite often.

First I tried to simply replace the part, but unscrewing the plate on the end of the assembly only revealed that the entire assembly has to be removed to get at this roller. Worse, once I discovered this unhappy fact, I tried to replace the plate with its 3 small screws only to find that I can't because the screw into a washer behing the assembly that now is impossibe to align with the assemble in place.

My down and dirty fix was to remove the other pieces of remaing rubber, expose the metal roller beneath and then wrap an appropriated thickness of electrical tape around the metal. Of course, there is no way to get a wrap that will not have a bump in it where the tape ends, so I wedged a piece of cardboard between the roller and the houseing and that lifted the pressure roller up enough so that it didn't hit the drum but still allowed enough pressure on the film to turn the drum. It sounded fine for the rest of the night.

Is there any way to remove and replace that roller WITHOUT taking out the entire assembly AND, if what I am seeing is correct, the solar cell assembly looks like it has to be removed also. This would require a complete realignment of the cell. If that's what needs to be done, the a curse on all their houses!

Is anyone familiar with this setup to suggest an easier way to replace a simple roller?

Thanks in advance.

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99


 - posted 04-28-2002 10:11 AM      Profile for Gordon McLeod   Email Gordon McLeod   Send New Private Message       Edit/Delete Post 
1 Remove the Pinch roller assembly( this requires first the removal of the slit lens mounting assembly
2 Remove the 3 small screws on the cover plate on the operators end of the roller assembly
3 Put a screwdriver into the slot screw on the end of the shaft and one in the slot screw at the other end and remove the screw from one end
4 slide the shaft out
5 put the new roller in and enjoy the fun of getting the the screws back in
realign the sound head

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Steve Guttag
We forgot the crackers Gromit!!!

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


 - posted 04-28-2002 12:46 PM      Profile for Steve Guttag   Email Steve Guttag   Send New Private Message       Edit/Delete Post 
Putting the three screws back in is an art that once mastered, isn't that big a deal.

Let gravity work in your favor. Hold the roller assy. vertically so the ring with the threaded holes rests on the casting. Now take your tiny screws (one at a time) and try to find the threaded hole by gently rotating the ring. Once you get the first ones, the remaining two should go quite quickly.

Steve

------------------
"Old projectionists never die, they just changeover!"

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Randy Stankey
Film God

Posts: 6539
From: Erie, Pennsylvania
Registered: Jun 99


 - posted 04-28-2002 12:57 PM      Profile for Randy Stankey   Email Randy Stankey   Send New Private Message       Edit/Delete Post 
That assembly is a real "Can of Worms" isn't it?

Here's my trick:

Go to Radio Shack and get a packet of small machine screws that match the ones that hold the roller together. You'll find that they come in many different lengths in one package.

Get one extra, extra long screw and put that in first. Yes, it will stick way out and won't hold things together right... BUT... You can use this screw as a "handle" to hold things together while you put the other two screws in. Then, when you have everything else back together, you can remove the long screw and put the proper one back in place.

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Dave Macaulay
Film God

Posts: 2321
From: Toronto, Canada
Registered: Apr 2001


 - posted 04-28-2002 01:28 PM      Profile for Dave Macaulay   Email Dave Macaulay   Send New Private Message       Edit/Delete Post 
Gord is right. I would add the helpful fact that removing the slit tube mounting block complete, without disturbing the slit tube adjustments to the block, means the assembly can be replaced )after fixing the pinch roller) without upsetting the sound adjustment much if at all, it should sound fine afterwards.
So you don't have to be afraid of doing the roller without a way to reset the A-chain.

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Brad Miller
Administrator

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


 - posted 04-28-2002 02:42 PM      Profile for Brad Miller   Author's Homepage   Email Brad Miller       Edit/Delete Post 
Frank, don't bother replacing that stupid pressure roller. Instead take a piece of rubber tubing from a Kelmar film cleaner's takeup shaft (or get an appropriate sized piece locally) and cut it to length and put it on the shaft instead to act as a spacer. From that point on it will NEVER wear out because it won't be touching anything and your films will be happier without it. Anyone who really thinks that roller does not embed dirt into the film needs to get themself some white leader and run a loop through a few dozen times. Heck, I can notice a print that came from a Simplex theater just by that dirt strip left on the print.


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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99


 - posted 04-28-2002 02:46 PM      Profile for Gordon McLeod   Email Gordon McLeod   Send New Private Message       Edit/Delete Post 
So what keeps the film tight across the scanning drum for the flywheel to do its job
I mutch prefer the felt ones that I think wolk still supplys

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Rick Long
Jedi Master Film Handler

Posts: 759
From: Toronto, Ontario, Canada
Registered: Nov 1999


 - posted 04-28-2002 03:51 PM      Profile for Rick Long   Email Rick Long   Send New Private Message       Edit/Delete Post 
Well, at least we can blame Frank this time for sending Brad into spasms.

If the flanges on the roller are sufficient to provide the required tension on the film without the G-1987 idler roller, would simply not a short (cut to size) aluminium tube do the trick (since it never touches the film anyways)?


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Brad Miller
Administrator

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


 - posted 04-28-2002 03:54 PM      Profile for Brad Miller   Author's Homepage   Email Brad Miller       Edit/Delete Post 
I'd have to go back in and look at one to give you a specific description Gordon, but I did this years ago (before digital was commonplace) and the audio did not suffer one bit. If memory serves the edge guides simply rode on the sprocket area of the film sort of similar to a Cinemecannica soundhead to provide the necessary tension. All I specifically remember was that the picture was no longer abraded.

Sure it's minor and it takes a certain number of runs to be noticeable, but it IS damage and that is unacceptable. (You are certainly right Rick, I feel this is a very stupid design with little respect for the film which irks me every time it comes up. I wish Strong would redesign it.)


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Frank Angel
Film God

Posts: 5305
From: Brooklyn NY USA
Registered: Dec 1999


 - posted 04-29-2002 05:35 AM      Profile for Frank Angel   Author's Homepage   Email Frank Angel   Send New Private Message       Edit/Delete Post 
Thanks for the tips, guys. Seems like the same story I get from my automechanic --"Sorry, but I have to take out the entire engine block to fix a screw on the air conditioner compressor."

And Brad, you are preaching to the choir....the first time you pointed out the fact that the roller does indeed press against the emulsion, especially when it is still hot, convinced me. As I said, I have felt rollers in one booth, but even that doesn't seem to be a much better solution as they still forcing the film between them and the sounddrums. If I understand your fix correctly, you want to eliminate the roller completely and just use the tubing as a spacer to keep the spring loaded flanges properly spaced apart, right?

Since the rubber is now completely off the roller, that reduces its diameter considerably; wouldn't just leaving it that way accomplish the same end? In other words, the reduction of the diameter of the pressure roller will now prevent it from touching the film. Had I not wrapped it with tape, I would have been home free (although the center of the roller is corrigated metal and it looked too viscious to leave uncovered anywhere near film). As it is, I raised the pressure arm with a fold of cardstock to prevent the uneven tape from thumping against the sound drum. Evidently that holds the film in tight enough contact with the drum that the drum spins normally. As I said, the sound played perfectly the rest of the day. It sure would be nice not to have to disassemble that whole thing.

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Brad Miller
Administrator

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


 - posted 04-29-2002 05:47 AM      Profile for Brad Miller   Author's Homepage   Email Brad Miller       Edit/Delete Post 
That's basically the point, yes. However if you don't put some kind of spacer in there (meaning that rubber insert I mentioned), the flanges will be way too close together to run film on.

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Pete Naples
Phenomenal Film Handler

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


 - posted 04-29-2002 03:32 PM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
I'm with Brad here! A place that opened a year or so back had the usual terrible dust problems in the booth, and those rollers left lovely witness marks down the middle of the prints for weeks. Then there was the one that came with an egg shaped roller from the factory, I spent ages trying to figure out why it ahd such awful wow and flutter, it never entered my head that a NEW machine could have a roller in such a state. I quickly found out why there were so many spares of those rollers sent with the kit! They're a fiddly beggar to change too.

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Will Kutler
Phenomenal Film Handler

Posts: 1506
From: Tucson, AZ, USA
Registered: Feb 2001


 - posted 04-29-2002 05:38 PM      Profile for Will Kutler   Email Will Kutler   Send New Private Message       Edit/Delete Post 
How to hold small screws?

1st, there are a couple of nifty tools that have been around for decades and can be purchased at Sears. One is for straight slotted screws and the other is for Phillips...they are screw holders/starters specifically made for this purpose.

Ancient mechanics' tip: a little heavy grease on tip of screwdriver!

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99


 - posted 04-29-2002 11:33 PM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
Doesn't matter if Brad gets spasms or something else from them but if you carefully examine these rollers at regular intervals you'll see cracks that start to appear long before it actually falls apart. This allows you to replce the part before it causes grief. Stave G is right about the three screws. Let gravity work in your favor and if this is your first time order several extra screws so when you loose the practice screws you still have enough left to get it all back together. I've been in too many booths that have that part of the lateral roller assy. held together with only one or two screws!

Also if this is a multiplex check the others very carefully by looking through a powerful lens with some good light. Bet you'll find others starting to go as well. This is a typical problem.
Mark A GTS

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Frank Angel
Film God

Posts: 5305
From: Brooklyn NY USA
Registered: Dec 1999


 - posted 04-30-2002 03:34 AM      Profile for Frank Angel   Author's Homepage   Email Frank Angel   Send New Private Message       Edit/Delete Post 
Ok. So I am looking to see exactly WHAT is the function of that damnable cover cap on the end of the assembly? Is it just cosmetic? Or is it just there to stop dirt from getting into the rotating shaft?

After watching this thing frustrate me and two other good and honorable men, and after plying the neat tricks suggested on this board, only to be mocked....MOCKED I tell you, by the perversion of this inanimate object, did I begin to wonder if the simpler solution would be to silicone cement the thing in place. Not only would it satisfy the reason for this thing's pitiful existance, but it would also satisfy an organic life-form's instinctive desire to triumph over the evil that is this cover cap with its three vile little screws.

You say I have been working in the booth too long? Perhaps.

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