I was googling around for small glass beads, and I stumbled upon this auction.

http://cgi.ebay.com/Glass-Micro-Beads-for-...0QQcmdZViewItem

or these:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI..._PCN_BIX_Stores

Has anyone tried this? maybe with spray adhesive on blackout cloth?
Could it be a cheapo high-gain solution?
I think I may give it a try.

Check out the sellers other items.... some interesting stuff!

Here is a home made glass bead screen that was painted with white paint and sprinkled with 50-100 micron glass beads.
http://www.dvlachy.ic.cz/phpBB2/viewtopic....der=asc&start=0
Notice the results with ambient light in the 8th picture.

The original thread that this came from is here.
http://www.avsforum.com/avs-vb/showthread.php?t=653681

This shows a lot of potential once the proper bead size and applicatiion gets figured out.

Cool.
This might be a brainfart here....
But if there glass, could they be crushed or grinded to a finer bead size?

And then snorted?

Wait, scratch that last part.... ouchy

If they were crushed then they wouldn't be beads anymore. You would wind up with a bunch of jagged pieces. It's my understanding that it's the roundness of the beads reflecting the light that give the results.

If you crush them you lose the round shape and retro-reflective properties.
One of those eBay links looked interesting but the size of the beads varied greatly.

That sounds right.
I was just thinking if it were ground to dust consistency, the grains would still be round.
But they would go on flat, and it probably wouldnt work properly as you suggested.

So how do the bead sizes of those auctions compare with the experimentation so far?

I tested some retro reflective paint in a pressure pack, I wasn’t too impressed with the results. To see any gain you have to look at the screen from the source of the light, in this instance at the triplet. Moving off axis resulted in no gain at all. But don’t let my results deter you.

DJ

The results seem promising with the 50-100 micron beads. There are lots of different size beads that are used in blasting media.
http://www.caswellplating.com/aids/cyclone/blmedia.htm

I'm just not sure how "micron" compares to the "grit" sizes that they list. Or maybe it's the same thing?

Here's some interesting reading on the subject.

http://www.da-lite.com/education/angles_of...ails&issueid=29
http://www.diyaudio.com/forums/showthread.php?threadid=23795

Too bad the DIY thread just kindof died out.

I purchased 4 tubes of these to experiment with.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI..._PCN_BIX_Stores

I will post some experiments soon.

They have red too.

http://cgi.ebay.com/Red-Micro-Glass-Beads-...1QQcmdZViewItem

I was really just going to use bo cloth but the more I see I may have to give some stuff a try some day.

I'm not sure if I want my screen shining like a stop sign though.

I think you would mix the beads in the pant and apply one layer then cover that up with one more layer of plain white. I kinda liked the small beads better but some test would have to be done.

Neat find.

Link doesn't work

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI..._PCN_BIX_Stores

Try that Pagercam. Think it works now.

AV, thanks for the input.
Im thinking about just hitting the BO cloth with spray adhesive, and then the beads, then kind of misting a top coat of flat, bright white over that if the beads alone are like a crazy kelidescope stop-sign like you mentioned.

I will try a few methods in stripes, so anyone wants to,
feel free to suggest an application method for the testing.

Thanks for the link, looks real interesting and price isn't bad.
keep us posted on the results

Definetly!

I hope five containers will be enough. That was my ballpark guess, going by how they spread out on the cardboard in that picture.
The price is right as you said, Good combined shipping too, 45$ total for five. ssshhweeet.

You can get paint that almost clear or light white. If you mix in the beads you will get a fairly even coverage. Thin the paint so the beads can flow a little. A yard seed spreader might work. To throw a even pattern is a hard thing to do unless you go 100% full then you just pile the beads on but I would worry about clumping.

just do a one foot sample It may take a few tries to gey it right

Thats an awsome idea AV.

My adolesent days as a graffiti artist may come in handy on this one...
A nice 'fat-cap' on a can of krylon provides a very consistent, misty thick line. If I can get my "can-controll" back, I think I can get an even coat on there,
But Im going to also try the technique you suggest. Any specific suggestions on the opaque white paint

Another neat graf trick, is mixing spray cans. It involves boiling one can, and freezing another.
Sounds nuts, but it actually works. This was origianly done by graffiti artists to reproduce discontinued colors, like Krylon's 'Jungle green', or to make your own colors.
Ghetto-fabulous DIY!

Im going to also try the technique you suggest
I was thinking somthing like 60% flat-white satin, 10%silver, 30% thinner to start out
Im going to also try the technique you suggest. Any specific suggestions on the opaque white paint mix?

I don't like a lot of the laytex paints that now sell that are 'one coat' they are so thick that they won't self level so you need to thin them some and then a roler will give a nice even coats. I have not looked at all the paints in a long time so the color is up to you

You might try a sand blaster gun with the preasure turned way down, you know, one of those gravity fed ones that you power with an air compressor.

The auction says it can be mixed 5-6 lbs to a gallon of paint.
At that size, I think I could put it in my airless piston-pump sprayer with the pressure really low without hurting it. I might just have to get a new nozzle, and take the filter out.

But I see no reason to use a sprayer just yet. Im not even really convinced on mixing the beads with the paint.

I have a small, old-school 'Radiant' glass bead screen from super8mm times, and its my favorite, but its tiny, and all banged up. Anyway, if you look at it, the beads are just a very even glass layer. Thats what I want to try and replicate first with just spray adhesive on blackout cloth.
Simple-pimple

But,
Its likley with the flux in bead size, that it wont work so good, and it will have to be mixed with paint, and put on even-steven. Or, mabey just use paint, as glue... and try to sink an even layer of the microbeads on top,
mabey aid the eveness with a plywood samich', and clamps.

mmmmmmmm plywood samich'...

What sort of piant are you thinking of mixing it in? Sounds like it would be better to sprinkle on top of wet paint to get the reflection without having to go through paint.

Deflinetly. Im going to try just spary adhesive first. I would rather not use paint at all, other than to take the place of an adhhesive.

If the light is really bad off-axis, or if it looks like I just ate my last half of the sunshine acid...
thats when we need to worry about coating the whole bead i think.

somthing opaque, or like skim-milk consistency, to kill unwanted glare, but still fuse the light from bead to bead.

Theres a box on my porch!
Damn that was quick, turns out the guy was in my home state of RI,
and Im in Boston now, which is only 45 minutes away from RI.

Im finishing my midterms this week, so I wont be able to start playing with it till next week. :angry:

And Im having an enclosre custom re-built on a CNC, who knows how long that will take either

Although I do have a comercial pj at my disposal, and a 250 watt DIY pj I built for my niece and nephew here, so even if my new one isnt done, I can use those to test with. Should have some experiments posted next week

ooooh...
these looky nice!

There very close in size to the beads on the beat-up old glass bead screen I have. Tiny!

The variation in size is undetectable to the naked eye in the small amount I poured out to take a peek so far.


So Im contemplating the best way to apply them in a way so there is one layer, and there all nice and tight together. i was thinking about sprinkling the on the adhisive treated bo cloth in square sections at a time, then waiting for the glue to loose a little tac, and then tamping the sections down with a piece of MDF.
I will try somthing like that first.

Also this is the only way I could do it if I use spray adhesive, since it sets up so fast.
My only concern with spray adhesive is that it would dry too glossy, and interfere with the the way its supposed to work. Any opinions or suggestions?

So I had another idea after reading some info on dalite's site.
I think I will try the method in the above post, with one change...

Right after the spray adhesive go's on I think I will spray a coat of flat white on top, then sprinkel and tamp the glass beads. I want to try it this way, so its a matte finish uner the beads, and also to sink them into the matte a bit.

Heres the info on how its done at dalite:

"High Power™ has an additional advantage in that its special manufacturing process causes each of the beads to be firmly sunk about a third of the way down into the vinyl beneath it. This means that when the finished material is attached to a roller no beads will rub off when the screen is raised or lowered. This mechanical stability coupled with its exceptional resolution and 2.8 on-axis gain make the High Power™ material the best glass beaded screen on the market."

full article here:
http://www.da-lite.com/education/angles_of...ails&issueid=29

Here's another source of beads. Has a green tint though due to the silane coating used to improve adhesion.
But I'm posting this because they describe how to apply them.

http://www.misterart.com/store/view.cfm?st...oogle&WT.srch=1

you guys are pioneers!!

i hope this works!!!

I'm doing it if i does!!

Here is a thread that I started a while back. I just never got around to finishing the project.

http://www.lumenlab.com/forums/index.php?s...indpost&p=73291

Well not really, this has been attempted and pondered by many before..
But thanks for the words of encouragement!

Pitman, thanks for the link and input. Im gonna give it a carefull read tonight.

FWIW, many people dont recomend glass beads at all for home theater, because of the angle of incedence
problems, but this is still a fun experiment. I think dalite's are sort of made to get the best of both worlds, and if I can even slightly replicate that for my total investment of 60$, it will be cool.

Light or gain will not come free if you incress the front gain then the light will have to come from somewhere.
A large screen by its vary nature puts you in front of it so I would think that staying in the middle should be easyer than for a small screen. Is the wife really going to wach from the kitchen?

So the more you sink the beads the less gain? This might give you some control of the gain. 2.5 might be a little much.

Hey yoshua, any news?

Hello,
no news just yet, my new pj is so close to completion that its all I have been working on.
Although I am anxious to do this too.
At the very least, I think I will iron and or stretch my BO cloth today, in preparation for the bead coating...
which may lead to me just trying one section now.

Should have an update soon...

i've got my own theories but i don't really have the time and money to explore them at this time.
but between you guys working on the beads and also some of the avsforum folks as well...
i'm interested in seeing what comes of it.
best of luck fellas.

Your own theroys aye?
Thanks for the regards and interest.

Speaking of which... this is way of topic, but Im a drummer, and suddenly Im very interested in the material that my coated drum heads are made of. Its like shiny mylar on one side, with a matte white texture on the other side. I just may scrifice an old bass drum head when I do some comparison shots.

before you do that...
pay a visit to jo-ann fabrics.
they have a number of very reflective fabrics that could be used as a base for
a reflective screen.

Am I understanding the theroy correctly in the sense that you want reflection when the light hits the screen,
but you then want the reflection to "stay put" on the screens surface rather than bouncing back OFF the screen?

Just trying to grasp the principals correctly...

Sorry if this is a dumb question, but with all this talk about glass beads, etc., has anyone asked the local high-end paint store if they sell paint that is a substitute for a projection screen?

I have a place I go to all the time, these guys know their stuff..... I think I'll ask them. With a screen of 8'x6' it may be a good alternantive.

They make such a product called screen goo. You can google it to find there website. It is kind of expensive and aplication could be tricky as well. I think it has been reviewed here or avs forum before?

C'mon!!!

I was all excited about this thread.

Anyone ever get a prototype going???

I was too! I even got a bottle of teh same stuff from the seller on ebay! If I had my projector finished I would try some stuff out myself...

Sorry fellas,
My mini hass is at the 80% complteion mark...
im anxious to try this stuff, but i wanna finish the pj first.

Go for it Yoshua. Once the pig is over the grill, there is no way to escape being "barbequed"

Thanks Kv,
The pig is over the grill indeed, and roasting to a savory flavor.

I wont need as much gain as I though( Bright PJ )
My plogy-plog.... http://www.lumenlab.com/forums/index.php?s...ndpost&p=133999


Im still going ahead as planed with the screen. Arizona mentioned over in my plog that I might try a grey coat with the glass beads. I have been thinking about this myself too, in hopes to gain some contrast on my 150:1, 8.9" 1024x600 LCD.

I just have to tweek a few more vitals on the PJ.
I hope to start the glass bead screen experiment this weekend.

I'm very interested as well, but haven't checked with the local paint store about it. I finally have all my parts coming in and all time is spent on the PJ.

I'll report it as soon as possible.

OK,
Although Im still worlking on the PJ, I couldnt help but do SOMTHING with the glass beads. Application is very tricky.
Im using grey, latex rusto primer and spray adhesive on blackout cloth for now.
Its looking like I might want to nix the spray adhesive,
Or do smaller sections at a time.

This is looking like its going to either work amazingly well, or not at all.

The grey is totaly covered in bead on the right side, up to about the shadow of the window frame

and the darker spot in the middle left of the sqare is also bead treated.

I will project on this tonight, and see how it looks.
Im really, really curious now... I also left some just grey with no bead to see how that looks alone on the BOC.
This section will end up being above the triplet and in the middle of the screen. I wanted to make sure to try a spot that wasnt right on the center axis of the trip.

woah... ok
I couldnt project on the screen tonight,
I may or may not have gotten lucky w the girl of my dreams , who also is the chick who I would be married to if my parents were into arranged weddings...
After a concert of some exeptional Aussie musicians, the John Butler trio. Aussies rock!!! Dazz buddy, ya hear that? God bless the Aussie folk
I have serious Aussie envy tonight.
... such an incredibly weird and awesome evening.

OK breath..... breath..... breath...

And back on topic,

I only one class today, so I will come home, close the shades, and post some pics after class.
Right after I have some very nice dreams for a few hours

What can I say, we’re a talented lot. I haven’t heard all of their music but what I have heard I liked. He reminds me of a hippy for some reason, perhaps it is his dreadlocks.

DJ

Just an FYI.

Harbor Freight sells #8 glass beads - 25 lbs for 20 bucks. Only available at their local retail stores, not online.

Yeah, he's definetly a granola-muncher. There music is not exactly what Im into persay, but they seemed like great people, and were definelty tight live.
Austraila is also home to a fantastic virtuoso drummer I like alot, Mr Virgil Donati. That guy is a monster



What is the size of "#8"?

I just hung the screen, and Im going to do some tests now...

#8 is the most popular size. It's listed here along with many others.

http://www.mediablast.com/glass-bead-conversion.asp