Waves on BOC - wallpaper adhesive?

[neilc01]

I bought some projector screen cloth (vinyl style BOC) from an eBay dealer and I constructed a 140” screen using 2.5” x 1” pine from Home Depot (measurements from memory). The frame was strengthened with 5 vertical braces and metal “L” shaped brackets at every join. I stapled grey felt to the frame before stapling the projector screen cloth. My wife and I had two attempts to do this, but we still have significant waves that make the screen unwatchable.

Clearly, the screen material isn’t tight enough.

The eBay dealer suggested I use a backing board and glue the projector screen material to the backing board using wallpaper adhesive. Does anyone have any thoughts on this - type of material for backing board, brand of wallpaper adhesive? Unless I can get the wallpaper adhesive perfectly smooth, I’m going to have lumps and bumps that will be bad as the waves. I was thinking a heavy duty, slow drying vinyl floor adhesive may be the way to go – lots of time to roll out the wrinkles.

My alternative is to start again and go with some Wilsonart laminate. I can’t help but think that this might be the easier approach to getting a watcheable screen than dismantling the existing frame and gluing down the projector screen cloth.

Any suggestions or advice?

Thanks

[mechman]

I've only got a second right now... I'll add more later.


Make sure you use something absolutely smooth. You don't want any deformities pushing there way through. You also may want to go and view a couple of online videos for hanging wallpaper before you start. The other thing is at that size it's gonna have to have seams.

Also if you have any scraps let me know! I'll have more later today.

mech

[muzz]

Welcome to the Shack neil!!

I've never used BOC, but folks use it all the time on home made frames.

Did you start in the middle of horizontals, then work towards the corners?

Why did you put grey felt on there?
From what I've seen, most folks use a small strip(thin depth) of 1/2 round(or something) right along the OUTER edge of the FRONT of the frame, to keep the cloth from being actually against the wood.

Somebody with experience using it will stop in and give you a hand, but it sounds like a couple of mistakes were made.
No biggy though, they'll get ya straight.

m

[wbassett]

Hi neil and another welcome to the Shack!

It's odd they recommend a substrate, that almost defeats the whole purpose of going with BOC in the first place... ease of construction, no painting, and most important light weight.

Now you just lost all three of those benefits. Construction just went up and got messy, you may not be 'painting' but you will be brushing or spraying on adhesive so what's the real difference there? And it's going to end up weighing two to three times as heavy, maybe even more depending on the substrate used.

I've seen some of this for sale on eBay too. I'm not sure what company you bought yours from but one of them offers a screen frame kit that uses bungees to tension the screen.

I'd think you would need to be very careful when putting the BOC on the glue and substrate so no runs or tears happen (BOC is tough but not indestructible) and then you have to worry about any foreign objects on the substrate, or even a clump of glue for that matter that's heavier than other spots... they will show through as bumps and imperfections for sure.

I'd try to re-frame and staple it. Get some help though, it makes it a lot easier to keep it pulled tight while you put staples in.

neilc01 wrote:

My alternative is to start again and go with some Wilsonart laminate. I can’t help but think that this might be the easier approach to getting a watcheable screen than dismantling the existing frame and gluing down the projector screen cloth.

As long as the material isn't damaged I'd give it another shot at tensioning it. If you have a Michael's Crafts nearby, stop in and talk to them back in the artist supplies, not the craft paints up front. They sell artists canvas and used to sell stretcher bars and they can explain in person and detail exactly how to get the artists canvas tight, and that's exactly the same as what you will do with the BOC.

If that doesn't work, shop around for laminate prices. Home Depot and Lowes are definitely the most convenient place to go, but they also have been known to charge twice as much or more than a local lumber yard or kitchen center.

[neilc01]

Thanks everyone for the warm welcome and advice!

Muzz: My wife and I started at one corner and worked to the other corner in a clockwise direction. We did this because we thought we could get more tension on the cloth by having a bigger piece of the BOC to pull on. I guess we were wrong. I also had vertical banding on the first version of the frame, so my wife thought that two layers of thick grey felt would help provide a smooth surface on the pine frame, and also visually block out the banding. Again, it didn’t turn out as planned.

I had never heard of the ½ round around the front edges, but that would certainly help remove the banding. That’s a really good idea.

Bill (wbassett): I think I will follow your advice and re-frame. Gluing the material down has the potential to permanently ruin the screen. I’m going to buy a canvas stretcher – hadn’t heard of them when we made the screens – to get it really tight.


I used dressed pine from Home Depot, buying the straightest pieces I could find. Reading other threads on this forum, I wonder if this material is rigid enough to hold the strain on the cloth over such a big frame. One thread suggested that you could be getting the screen material really tight, but as you progress, the pine slightly buckles, losing the tightness.

The previous frame, in hindsight, was too big (140”) for the resolution/quality of my projector (Epson Moviemate 20 – my first projector), but I was thinking the large size would be OK with a projector upgrade in the future. If I make the new frame at 130”, I can easily cut off the screen material with a knife and have enough extra to fold around the smaller frame. And, I don’t want to spend all weekend pulling out staples!

I’ll find a better quality of wood to use (my only local options are HD and Lowes) and put the ½ round the front edge. I’ll start at the middle of the top longest length and staple a few inches, then do the same at the bottom longest length, then at the middle right shortest length, then middle left shortest length; continuing in that manner until I get to each corner. I’ll use craft pliers to tighten the material.

Thanks everyone!

[brent_s]

Neil, sounds like you've probably already found some proper stretching directions somewhere. But, just to confirm, here's the first decent set I found using Google. I think I did 5-6 staples at a time as opposed to the 2 in these instructions. And here's a step-by-step with photos of a DIY screen build.

You can definitely distort the frame if you crank too hard on the canvas, but I don't think that would create waves in the material. I made a 6' wide screen out of 1x3 material as well and ended up with a little bowing, but nothing that annoys me enough to redo the screen...3 years later. For the size screen you're going for, you may need to step up to 2x4 material.

If you could *settle* for a 100" diagonal, you could simply get a nice 4'x8' sheet of plywood, 3/4 would probably be best. Then use your weapon of choice to cut material from the field to create a solid frame that should be square, plumb, strong, and light.

Just my .02. I couldn't find a Moviemate 20 at ProjectorCentral or Epson, but they do have a PowerLite Home 20 or Moviemate 25. Even at the rated lumen output (most projector produce less as they age or after calibration), neither of those models has enough output for 130" screen 1.0 gain screen...ProjectorCentral's calculator puts them in the 10-12fL range. Even 100" only gets you up to 15-17, depending on which projector you have. The recommended target is 16fL for a full darkened room.

-Brent

[neilc01]

Brent

Thanks for the additional information and support. I'm going to dismantle my screen this weekend and start again, this time with the canvas pliers and the correct approach!

My projector is the Epson Moviemate 25, with the built in DVD player. I know it is, at best, an introductory model, but I've had my money's worth out of it. Currently, my son's playing his Wii through it.

Once the screen is fixed to my satisfaction (I'm still half tempted to forget the cloth and go the Wilsonart DW route) I'll upgrade the projector.