Fixing Visible Folds in Theater Screen

[Chris Haller]

So, the theater I manage part time made the distinct choice of leaving its screens folded in its packaging for many, many moons. This has resulted in a handful of our screens having incredibly visible fold lines in the these screens. The option of purchasing and installing new screens in these theaters has been nixed pretty aggressively, of course. And the installers, who visited shortly after theater operations started, kinda just tossed their hands up and said they couldn't fix it, I guess - all of this happened before I started here, of course.

Anyone here ever come across this issue and know any meaningful actions a lowly theater manager could take to try and fix this? Might there mechanisms somewhere to allow me to tighten these screens at all to correct for these folds? Or should I just try to live with it, as I currently have to.

[Ryan Gallagher]

Contact the screen material/frame manufacturer and ask for advice?

[Chris Haller]

Contact the screen material/frame manufacturer and ask for advice?

Fair. Just figured I'd ask around if the crew here had ever had to tackle it themselves.

[Mark Gulbrandsen]

They must be Harkness Matte White screens. They typically folded them in boxes to ship, unless you asked for rolled in tubes, at much extra cost. Anyway, the latter is the ONLY way to ship screens. I only had them shipped in boxes once or twice, mainly because I could always see the very slight lines where the screen was lightly folded. I have had minor creases and such on other screens, but never anything as major as yours. I always fixed them with a heat gun I use to do heat shrink on cables. It always worked ok for me... Not that It's the right thing to do. You can also try cranking up the heat at night, but your cheap skate owner might complain about that. I also think the owner underestimates his customers ability to go to another theater once they notice the creases. I certainly would...

[Randy Stankey]

How long has it been since the screens were installed?

Creases usually flatten out over time. I've seen a few newly installed screens with creases and, over a span of a few days or weeks of being held under tension, they should go away. If they don't go away on their own, check the screen tension to be sure it's even across the face of the screen. It should be "tight as a drum," so to speak, but not so tight that things break or tear. If you thump it with your finger it should bounce back.

How is the screen installed? Laces or springs? If it's laced you might be able to tighten the screen a bit. Screens should be checked for tightness every so often, regardless of the method. In your situation, I'd definitely check. If you've had the original installers look at it but they threw up their hands, I'd expect it to be tight but, as they say, two sets of eyes are better than one. Right?

If the screens have been there for a long time, more than a month, but they still haven't flattened out even if the tension is right, the creases probably aren't going to go away any time soon, if at all. If that's the case, I'd go for what Mark suggests. Carefully apply heat with a heat gun...but WATCH THE TEMPERATURE! Keep the heat gun set LOW! LOW! LOW! Under 200º F. More like 150º or even less, depending on the heat gun you use. (If the temperature will go that low.) Maybe, you can use a regular hair dryer set on medium or low temperature.

We use heat guns to do rework at my job. The highest temperature that's supposed to be used is between 250º F and 350º F and the absolute maximum is 500º F but I've picked up heat guns that are set to over 800º! It's easy to pick up a heat gun, thinking that it's set to the right temperature but some butthead turned it up because they wanted to get done faster. Then, when you go to use the heat gun, you accidentally end up burning the part. The smell of scorched thermoset plastic is terrible! Worse than regular plastic! It's happened to me, a couple of times! Check the temperature of your heat gun before you start working! You don't have to ask my how I know!

Anyhow, set your heat gun/hair dryer on low temperature and start on an edge or corner where it won't be seen if there is an accident. Gently heat the screen and carefully "iron" it flat, using a piece of smooth plastic, from the back side. Work along the crease, from the edges to the center. Just use common sense. If it doesn't seem to work the way you want or if you start to see damage, STOP! Pull back, regroup and figure out another way!

You should be able to minimize the creases if not make them disappear, all together. If they don't, tell your bosses, "Lesson learned!"

There's a time and a place for frugality but the public-facing feature of your entire business shouldn't be one of them!

[Ryan Gallagher]

Yeah the inquiry about how long they have exhibited this issue is valid.

also. Are they visible on a projected image? Or only when looking at a screen lit by high angle house lights. If the latter, maybe just ignore it a bit longer and see if they relax out.

at my theatre others made an issue of very minor dimples of the house air pushing the screen against the frame. Only visible without an image when looking at it from where no one sits. Their solution IMHO is worse than the problem. They pushed the bottom bungees downstage with a clamped board.

But because the board could not function the same in the corners, now we have brightness/color issues in the bottom corners! It was crazy how inaccurate it was when we had a temp 4k laser in for a premiere. They shot their colors and it was like “WTF is that”!

I’m about to make them remove that hack, but trying not to insult the coworker who made it his project.

[Chris Haller]

We've been open and exhibiting movies almost a year. That's how long the creases have been there as well, which is what irritates me. They opened like this!

[Randy Stankey]

I’m about to make them remove that hack, but trying not to insult the coworker who made it his project.

I hate bungees. You can't adjust them or tighten them like you can with lacing. Lacing is a lot cheaper, too. You can get a 600 ft. spool of it for around $100-$150. You should be able to lace at least two screens with a 600' spool of it and still have a bunch left over to use on odd jobs, around the theater. The stuff comes in handy!

I laced in the screen at Mercyhurst, nearly twenty years ago and, to this day, it's still tight as a drum. Just every so often, go back and check to see if the laces need tightening. Tug on them with your finger. If there's too much slack just go around and pull on the laces to progressively tighten them. It shouldn't take more than thirty minutes.

If Ryan's screen had been laced, it could have been fixed instead of Jerry rigging it.

The problem is that lacing is kind of a PITA but, once you start getting the hang of it, things go faster.

Chris, if your screen is still creased after a year you've either got permanent creases or else the screen wasn't tensioned enough. (Or, maybe not tensioned evenly.) You might be able to iron them out with a heat gun and a block of Delrin or something. I don't know for sure. I'd have to see it.

[Gordon McLeod]

I use 3' long black heavy tiewraps (zipties) and then I can just go back latter and add more tension as required

[Ryan Gallagher]

I hate bungees. You can't adjust them or tighten them like you can with lacing. Lacing is a lot cheaper, too.

Heard, I think one consideration for us where bungees may be more desirable is that we often have ALOT of action on the strip of stage downstage of the screen... often whole casts that are rarely cognizant enough to avoid touching the screen. Worst cases our stage carpenter will go behind the screen and be the "voice of the screen" telling people to take two steps downstage.

With bungees if someone does manage to lean into the screen it is a bit more forgiving, cause otherwise the only thing to stretch would be the screen itself.

[Randy Stankey]

... often whole casts that are rarely cognizant enough to avoid touching the screen.

Yup! I got the T-shirt for that one!

We used the screen at Mercyhurst for PowerPoint and multimedia during lectures and things. There would often be a whole flock of people on the stage. We were constantly warning people not to touch the screen.

We had a graduation ceremony where the graduates would enter the stage from the Stage-Left stairs and walk across the stage where the officiant stood near the lectern at Stage-Right. The screen displayed the graduate's name, major and some cute graphics, etc. Despite the warnings, one of the A-hole students walked by and high-fived the screen! Right there in the middle of everything! I was pissed!

The screen is a Hurley Super-Glo with a gain coating. There was a hand print on the screen, after the incident, but I was able to clean off 90% of it. It was mostly just a clean spot in the dust.

Considering that it was hung on the fly system, we were able to keep the screen pretty clean except for minor incidents. There were a few small marks on the screen but nothing that showed during presentations.

[Mark Gulbrandsen]

We've been open and exhibiting movies almost a year. That's how long the creases have been there as well, which is what irritates me. They opened like this!

What really irritates me is that some dealer actually sold these screens to be shipped in boxes in the first place. Avoid THAT dealer in the future.

And I have no idea why on earth Harkness started the 'LETS SHIP OUR SCREENS IN BOXES TREND". I serviced theaters where their Harkness screens had hung for five or more years, and you could still tell there were fold points in them. You could probably keep stretching that 15' X 32' screen out to Eyemax size, and those fold areas would still be noticeable.

[Marcel Birgelen]

Well, what idiots do fold a cinema screen? We did... We had a big vinyl-type perforated screen lying around coming from a re-install. Instead of destroying the screen, they kept it in one piece and I opted to keep it and store it. The screen itself was still in pretty good condition. We've stored in a big box for a few years and have since given it away to a location that had its screen destroyed due to severe water damage. They cut it to size, being able to cut around some of the biggest problems, but due to the way it was stored, visible folds had developed across the entire surface. Since they didn't have anything to loose, they opted to try to use heat guns on it after rigging and properly stretching it. It worked pretty well. If you really know what to look for, you can still see some folds on close-up, but I can't make them out during presentation.

Now, this message comes with a big disclaimer: If this works as intended or not probably depends mostly on what your screen material is made from. Most plastics loose their capability to retain form when being exposed to a certain amount of heat, but a heat gun can obviously also damage your screen beyond any reasonable repair if you use it incorrectly.

[Randy Stankey]

Assuming that the movie screen is made of Polyvinyl Chloride (PVC) or at least something similar:

According to Wikipedia, PVC melts at temperatures between approx. 100º C and 260º C. (depending on its exact composition and form) and it's transition temperature (the temp. where it begins to melt) is around 80º C. (175º F.)

If I was doing this job, I'd start out with my heat gun set at a temperature as low as I could set the gun for and work up. The heat guns where I work can go as low as 120º F and as high as 1,200º F. I'd start at 120º and work up to 150º but I'd be hesitant to go above that.

[Mark Gulbrandsen]

Randy,
It's the distance from the heat gun nozzle to the material that matters. The gun I used in the past to do it was my heat shrink gun which had three heat settings. I ALWAYS started out on the lowest temp as you say. But if the end of the nozzle happens to get too close, the gun temp may still rise too high, damaging the material. The few times I've had to do this sort of thing I always went very slow. till the wrinkle or crease disappeared and stopped immediately... I'm also lucky in that the crease's I had to deal with was in an outer edge area each time.