Film-Tech Forum ARCHIVE: Simplex Tension Band adjustment

my profile | my password | search | faq & rules | forum home

»	Film-Tech Forum ARCHIVE » Operations » Film Handlers' Forum » Simplex Tension Band adjustment (Page 2)

This topic comprises 3 pages: 1 2 3

Author

Topic: Simplex Tension Band adjustment

Tim Reed
Better Projection Pays

Posts: 5246
From: Northampton, PA
Registered: Sep 1999

posted 03-02-2008 09:18 PM

It's okay, Mark, no one expects you to know everything. The numbers don't reference anything, they're just tics. Other projectors are beside the point; he's asking about a Simplex.

| IP: Logged

Louis Bornwasser
Film God

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

posted 03-03-2008 07:00 PM

Hey! Don't fix that problem....I repair a lot of intermittents!

Seriously, on our overhaul machines, we set up the machine to track correctly at minimum tension. If we cannot start to attract proper "labor" we are seriously considering removing the "taper" on the shaft behind the knob. That way, they can set it anywhere they want and not destroy an otherwise wonderful machine. Louis

| IP: Logged

Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 03-03-2008 09:37 PM

quote: Tim Reed
The numbers don't reference anything, they're just tics. Other projectors are beside the point; he's asking about a Simplex.

quote: Louis Bornwasser
Seriously, on our overhaul machines, we set up the machine to track correctly at minimum tension. If we cannot start to attract proper "labor" we are seriously considering removing the "taper" on the shaft behind the knob. That way, they can set it anywhere they want and not destroy an otherwise wonderful machine. Louis

Louis.... I see most movement failures due to lack of oil... but there are ones now and then whose cam pin and star slot obviously went through alot of sufferring.
Removing the taper isn't really necessary... you can shorten the shaft...removing the knob and then "fix" the shaft at the correct tension amount. The downside is that different film brands do require slightly differing tension settings to achieve the best results.

Mark

| IP: Logged

Nicholas Stevens
Film Handler

Posts: 6
From: Munroe Falls, Ohio, USA
Registered: Feb 2008

posted 03-03-2008 11:28 PM

OK so I tried to set the tension on all the projectors here and I kinda ran into a problem. I can't get the tension bands to be able to be set on anything below 3 on some of the projectors without the gate having to be so tight that they won't close and lock. Is it possible for the tension bands to be stretched or need replaced because of the excess tension that was placed on them before?

| IP: Logged

Steve Beverly
Film Handler

Posts: 83
From: El Paso, Tx.,
Registered: Nov 2007

posted 03-03-2008 11:34 PM

quote:
Dudes...
I find that line absolutely hilarious [Big Grin] ! With the amount of unsteadiness we typically see in the crapo release prints of today I am finding more and more Simplex's, Century's, Christies, Norelco's, etc., whose gate tension is turned all the way up in an effort to get something stabilized on the screen.

Mark

quote:
How much should we be willing to alter our practices due to lab errors? What if release prints start to come out all with the same misprinted SR*D tracks what becomes correct? To calibrate the readers to pick up the misprinted tracks or to achieve Dolby spec.? All in all I think the labs need to get their acts together.

What exactly are the problems the labs are having, what are they doing wrong and what can be done to correct these mistakes? ( I ask this as we are getting ready to process and print our own work and would like to avoid the mistakes some of the larger facilities are apparently making.) [Cool]

| IP: Logged

Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 03-04-2008 02:03 AM

quote: Nicholas Stevens
I can't get the tension bands to be able to be set on anything below 3 on some of the projectors without the gate having to be so tight that they won't close and lock. Is it possible for the tension bands to be stretched or need replaced because of the excess tension that was placed on them before?

..did we ever get what model of Simplex you have there? wonder if that adjuster got wigged out somehow for you to say "below 3", for 1 to 3 would be lesser tension than from the 3 to 5 position.

Sorry, bands don't stretch being steel, just get thin in the middle.

| IP: Logged

Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 03-04-2008 04:28 AM

quote: Steve Beverly
What exactly are the problems the labs are having, what are they doing wrong and what can be done to correct these mistakes?

Its mainly because they print and then process at Warp Speed 7! Eliminating greed is the only way to fix the problem...

Mark

| IP: Logged

Louis Bornwasser
Film God

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

posted 03-04-2008 05:50 AM

Once tensions are too high for too long, then the intermittents are fried. This is operator induced intermittent failure.

Replace the intermittents!

(While it is true that some projectors/intermittents leak more than others, we have a slow leak problem with Simplex. On Century, a careful intermittent overhaul will result in an intermittent that will only require a top off every 90 days or so. (One plex waited 13 months and only lost one intermittent; one leaked faster than the rest.)

We do not see lack of oil so much since we reduced the leakage, but we do see excess tension every day.

With reduced tensions, 25-50 years is possible on a Century. Louis

| IP: Logged

Tim Reed
Better Projection Pays

Posts: 5246
From: Northampton, PA
Registered: Sep 1999

posted 03-04-2008 06:57 AM

Louis's group absolutely does the best (and quietest) intermittent rebuilds on the planet! His intermittent guy grew up in the watchmaking business.

quote: Markie G.

That's funny. It must've taken you all day to come up with that.

| IP: Logged

Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 03-04-2008 04:59 PM

Tim... Less than one second actually....

Monte...

Actually spring steel does indeed stretch.. it also looses its temper over time from both heat and from being stretched repeatedly as in a clock spring. If you think in terms of a clock spring(Yes Tim... I also have a clock making background! Monte has seen some of them...)it can only be wound and unwound so many times over the years before it begins to loose torque. This is because the repeated wind and unwind causes the temper to break down and eventually the metal weakens(and the spring may even break) With less torque then the clock either doesn't run as long or it doesn't keep time as well because there is not enough constant tension against the escapement. Similar things happen to the trap bands if the tension is left turned up all the way for very long periods of time... on just about all machines with bands the equalizer spring will buckle permanentley and the bands will stretch somewhat as well.

Mark

| IP: Logged

Ron Funderburg
Jedi Master Film Handler

Posts: 814
From: Chickasha, Oklahoma, USA
Registered: Nov 2007

posted 03-05-2008 02:58 PM

As general rule I replace tensions bands every other year weather I think they need it or not. If I can't achieve a good stable picture with tension setting below 5 (and there is no problem with the intermittent) I change them as well no matter the age.

| IP: Logged

Nicholas Stevens
Film Handler

Posts: 6
From: Munroe Falls, Ohio, USA
Registered: Feb 2008

posted 03-05-2008 05:19 PM

I have the gate's adjusted to be as tight as they can be with still being able to close and lock correctly and the tension knob still has to be set at or above 3 (1 to 5) for the film to be stable on screen. so i just ordered all new tension bands for these projectors. I'm going to change them out and see if I can't get the settings below 3 on the knob and if all goes well be able to loosen the gate up some also.

(by the way, they are the simplex 1060's)

Just outta curiousity, how hard is it to rebuild the intermitten's? Is it something that can be picked up easily or no?

| IP: Logged

Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 03-05-2008 06:35 PM

quote: Nicholas Stevens was the last to post

Apparently it helps if you also know clocks [Wink]

. Rebuilding an X-L intermittent is relatively easy but it does help to have a bore gauge to mesure both the cam shaft bore and star shaft bore to ensure proper oil clearance and that the holes are still round [thumbsup]

. With grind house movements or movements that have been abused the front cover bore wears to an oval... Simplex 35/70 is the worst for wear with a very short movement life if you run alot of 70mm... A friend ran Sound Of Music on his "Howard Straight" Simplex 35/70's for about a year and had to change movements once during the run.

Mark

| IP: Logged

Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 03-05-2008 08:48 PM

quote: Mark Gulbrandsen
Simplex 35/70 is the worst for wear with a very short movement life if you run alot of 70mm...

..probably both situations that you mentioned is due to the cast iron INT cover used without any pressed OILITE bearings to support the starwheel in the cover itself and the stronger torque needed to pull that wide film through the trap (prob why the "JJ" unit was a lot better in handling film than the XL-35/70 unit-just can't imagine running 70 in an XL the way how compact that machine is compared to the Century)?

Interesting that a XL movement was designed to do both film sizes without any enhancement for the larger film - or at least some sort of compensation where the assembly can handle both film sizes on an equal basis.

Yes, Mark, those clocks were neat and I did forget about the spring steel tension getting weakened with time ....

-Monte

| IP: Logged

James Westbrook
Phenomenal Film Handler

Posts: 1133
From: Lubbock, Texas, Usa
Registered: Mar 2006

posted 03-06-2008 01:28 AM

To me, intermittent movement rebuilding is like having an automatic transmission rebuilt: Best be done by a professional. Most of the fellows here can rebuild intermittents. I can't.

| IP: Logged

All times are Central (GMT -6:00)

This topic comprises 3 pages: 1 2 3

Printer-friendly view of this topic

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.