Film-Tech Forum ARCHIVE: Film is pulling projector out of frame

This is topic Film is pulling projector out of frame in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=007701

Posted by Dan Chilton (Member # 2288) on 12-20-2005, 09:42 PM:

I noticed this starting last week: throughout the course of a film, the framing slowing pulls itself down. It wasn't too bad last week (if the film started with the FRAME letters perfectly horizontal, it would end with a 10 degree CCW rotation). However, during tonight's film, I started with the FRAME nob perfectly horizontal, and when I checked on the film 30 minutes later it was nearly 45 degrees CCW out of frame! I don't know how the audience didn't pick up on that!

I corrected the framing, but as I did I could feel the film trying to pull the framing back down. What gives? Or more importantly, what do I need to tighten to correct this? I'm on a Simplex XL, btw.

Posted by Olivia Coleman (Member # 3193) on 12-20-2005, 09:52 PM:

My stab in the dark would be something with the intermittent shoe...

Posted by Dan Chilton (Member # 2288) on 12-20-2005, 09:55 PM:

Anyway to test that?

Posted by Olivia Coleman (Member # 3193) on 12-20-2005, 10:12 PM:

Umm, I'm not sure... I would see what the tension is like... Do you have any jumping on screen at all? Or is it just a slow shift out of frame??? (I'm no tech, just using my own booth knowledge...)

Oh... I thought of another suggestion: your intermittent may be be loose or almost done??? I'm really not sure about this one exactly...

Posted by Dan Chilton (Member # 2288) on 12-20-2005, 10:17 PM:

No jumping on the screen. From all appearances it's a steady picture... only it's slowly, slowly creeping southward.

Posted by Olivia Coleman (Member # 3193) on 12-20-2005, 10:18 PM:

Very strange... Check editted note on previous post...

Posted by Dan Chilton (Member # 2288) on 12-20-2005, 10:27 PM:

I'll baby it for the last show and then call my tech tomorrow.

Posted by Olivia Coleman (Member # 3193) on 12-20-2005, 10:28 PM:

Alrighty... [Wink]

Posted by Dan Chilton (Member # 2288) on 12-20-2005, 10:39 PM:

Thanks for you help Olivia! [Smile]

ALSO: I don't know if this has any relevancy, but the framing doesn't move when there's not any film running through the projector. When I flip on the manual power, the framing is as steady as a rock.

Posted by Monte L Fullmer (Member # 2797) on 12-20-2005, 11:55 PM:

Sounds like gate tension is WAY too tight and pulling the assembly around. What kind of XL do you have -curved gate or straight gate? Newer models have an adjustment allen stop that loves to turn in after so many times the gate closes, thus putting more tension on the film than needed and causes the intermittent assembly to "pull" around due to so much tension and going out of frame. The allen stop screw is inboard below the aperture opening on the trap assembly.

Proper adjustment is when the intermittent shoes on the gate just barely make full contact with the sprocket when gate is closed with film loaded.

If the shoes looks like they want to "crawl" under the sprocket, the gate is closing way too tight.

good luck - Monte

Posted by Aaron Sisemore (Member # 145) on 12-21-2005, 12:59 AM:

The cause of this is 99% of the time from the little leaf springs that provide tension against the intermittent movement against the framing carriage becoming loose or broken. The framing will slowly just move itself out with time. Replacing the leaf springs cures the problem, I have run across this problem numerous times, this is the cause and fix.

-Aaron

Posted by Dick Prather (Member # 1136) on 12-21-2005, 01:08 AM:

That is a common problem on a X-L or Simplex 35 if the intermittent carrage becomes loose. Look in the X-L manual on page 1-22 of the green version. The P-1705 framing cam retainer plates have worn to a point were they need to be adjusted or one of the newer spring steel versions have broken or come loose.

The combination of the retainer plates and the shutter compensator give enough tension to hold the framer in place. Adjusting or replacing the worn parts should correct this. Most people replace the both older plates with the newer spring ones. I sometimes use two on each side for better tension like they do in the 35/70 machine. Proper gate and intermittent shoe tension can also be checked.

The back door needs to be removed and the intermittent removed to do this properly.
Dick

Posted by Monte L Fullmer (Member # 2797) on 12-21-2005, 02:45 AM:

Thx for the help also on this for usually it was the excessive tightness of the trap and gate assembly that did it for me with my experiences with this.

Need to work on a lot more "XL" machines that have problems...I work on ones that run very well.. lol.

-monte

Posted by Richard May (Member # 2627) on 12-21-2005, 05:03 AM:

Aaron is correct. I have run across this many times on the strong projector. It has always been the spring.

Posted by Mark Gulbrandsen (Member # 72) on 12-21-2005, 05:09 AM:

Well we assume that he has Simplex's but I didn't read that in any of the posts. Framing drift can also happen to Century, Ballantyne, and others...... but we'll assume its Simplex.

When you install the new springs in place of the old style clamp blocks and so you don't have to deal with removing the lower block which is difficult to get at because it is behind the gear sector on the carrige, just install two thicknesses of those springs in place of the upper or easy to get at block. This will effectively give you the correct amount of tension you need and you won't have to remove the carrage stopper screw and rotate the carrage off the intermediate framing gear, nor will U be fishing parts out of the oil sump. Also be ready with the proper size screw driver as the retaining screws can be a pain to crack loose... the screws have special flat heads to clear areas of the framing carrage as it rotates!

quote:
However, during tonight's film, I started with the FRAME nob perfectly horizontal, and when I checked on the film 30 minutes later it was nearly 45 degrees CCW out of frame! I don't know how the audience didn't pick up on that!

Good projectionists don't rely on the audience to pick up on whats going wrong with any given presentation! They check frequently to be sure that nothing does go wrong.

Mark

Posted by Louis Bornwasser (Member # 3063) on 12-21-2005, 09:11 AM:

Dick & Mark have nearly said it all correctly. One add on: (I am assuming this is an old XL) the screws that hold on the blocks are too long to use with the spring clips, so cut down or replace the screws with the ones for the leaf springs. Sometimes 2 leaf springs isn't enough. Double up ONE of them. Also, when finished, be sure you still have full travel on the framer This is an inexpensvie fix.

Congratulations of doing an excellent job! Louis

Posted by Dan Chilton (Member # 2288) on 12-21-2005, 01:21 PM:

quote: Dan Chilton
I'm on a Simplex XL, btw.

And yes, it's an old one... curved gate. After speaking with my tech, he's positive it's the framing shaft friction disc washer (P-1752). According to him, they get worn down over the course of a few years, and should probably be changed every two years or so.

I'll have to wait until tomorrow to pull the framing collar off so I can get a look inside, but until then I have a couple of vice grips attached to each end of the the framing shaft to hold it in place. If that doesn't end up being the case, I'll try some of the other suggestions listed here.

As always, thanks a million for all the helpful comments! [Smile]

Posted by Mark Gulbrandsen (Member # 72) on 12-21-2005, 01:33 PM:

Don't ya just love these guys that think they are techs.... Time for your tech to go back to school or join us here on Film-Tech! That washer and the framing shaft have little to nothing to do with keeping the machine in frame. That part is merely the washer that holds the flat rubber shaft seal in place...... A properly tensioned intermittent carrage will hold frame without the framing shaft or gears in place at all.

Good luck... you may need it ... or better yet repair it yourself.

Mark

Posted by Gerard S. Cohen (Member # 994) on 12-21-2005, 02:52 PM:

I think we've established in Film-tech long ago that proper framing, (setting the intermittant, film loops, etc.) will remove the need to rack focus via the framing knob.

Perhaps in the aforementioned booth there exists someone who habitually starts out of frame, racking focus so often as to loosen the assembly through premature wear?

Posted by Mark Gulbrandsen (Member # 72) on 12-21-2005, 05:07 PM:

Gerard,
You are absolutely correct! Excessive manhandling of framing mechanism wears that area on both of the clamping blocks and on the framing sector itself....

Have a happy Holiday!

Mark

Posted by Randy Bowden (Member # 587) on 12-21-2005, 06:24 PM:

I Definitely agree with Mark, you do not need to replace the lower spring, just the upper. The problem you are having can also be a symptom of a gearbox just about to die, what happens is the upper gear gets worn down to the point that it is vibrating the machine out of frame (I have experienced this more than once) I just replaced an SH1000 gearbox last month with the same symptom of the framing drifting, when I arrived at the theatre there was no oil in the gearbox. If you do have a gearbox soundhead, check for excessive gear lash on the upper sprocket shaft, there should be very little.

[ 12-22-2005, 12:14 PM: Message edited by: Randy Bowden ]

Posted by Andy Bergstrom (Member # 360) on 12-22-2005, 09:31 AM:

Is there any chance of shutter compensator(?) damage by continuing to operate the projector with the intermittant moving or getting pounded out of frame?

Posted by Cory Isemann (Member # 2517) on 12-22-2005, 10:48 AM:

Funny, Andy, I was going to inquire the same thing.

It's a bad thing to operate the framing adjustment all the way in either direction for extended periods of time, correct?

Posted by Monte L Fullmer (Member # 2797) on 12-22-2005, 12:59 PM:

shutter units are pretty durable. Just have to watch out for that guide pin in the fibre gear to get bent with the sudden movement.

Posted by Mark Gulbrandsen (Member # 72) on 12-22-2005, 05:13 PM:

I agree that the X-L shutter compensator is a pretty durable unit but a part that few understand. The parts likely to receive alot of wear from excessive use of the framing mechanism however do include both the male and female spliens in the compensator..... as well as the intermittent framing sector carrage, the main frame bore for the framing sector, and the framing gears themselves.

P.S. Monte: there is not a fibre gear in the compensator... the pin that couples to the steel gear is attached the female splein part. The pin generally bends from sudden stoppage of the entire mechanism or if someone suddenly stops the shutter.

Its always best to know what you are doing and to do what you know.

Mark