The end is near.....glass or plexi?

[ras2a]

Hope I can hit jackpot too.  Cheers minwah

[ras2a]

Just phoned up a local glass merchant and for a piece of: grey tinted & tempered glass @  25" x 25" x 4mm thick, the cost is

[Minwah]

Just phoned up a local glass merchant and for a piece of: grey tinted & tempered glass @  25" x 25" x 4mm thick, the cost is

[dreamcastninja]

clear plexi... won't shatter, easy to clean, looks awesome, won't streak up like glass when you clean it... plexi is awesome stuff

[Shifty]

clear plexi... won't shatter, easy to clean, looks awesome, won't streak up like glass when you clean it... plexi is awesome stuff

You'll be cursing the first time a scratch turns up in plexi.

IMHO glass looks better, has better reflectivity (looks authentic) and greatly resists scratches. Worth the extra $$$.

[dreamcastninja]

i've had my plexi for over 2 years now... not scratched at all

[RandyT]

You'll be cursing the first time a scratch turns up in plexi.

IMHO glass looks better, has better reflectivity (looks authentic) and greatly resists scratches. Worth the extra $$$.

Plexi is more scratch resistant than Lexan and many use Lexan for thir CP overlays.  If you are subjecting your window to that level of abuse, I'd say that something is a bit out of kilter with your playing style  

Also, "better reflectivity" is not a desirable trait for a window, unless you like extra bright room reflections overlaid on your game screen.

Don't let the fear of scratches shy you away from plexi.  I have been using it for a couple of years now and it hasn't a single scratch of any significance.

RandyT

[ras2a]

There must be some attraction with glass though, as so many people seem to use it.  Also I assume that tinted glass will cut down on reflections?...maybe not, I don't know.  Anyone comment on that?

I know I've asked this already but what is the best overall tint level to go for with glass?  There must be a common consensus?

thanks a lot

[versapak]

Also I assume that tinted glass will cut down on reflections?

I would think that it would actually make it worse. The darker it is the more mirror like it would be.

[ras2a]

Ok this is p***ing me off now.  I must have phoned up about 20 glass merchants today and most that offer the tinted glass only do either bog standard grey or bronze.  When I start talking about different levels of tint/transmission grades etc, I am met with the same vacant sounding responses.  They think I'm a friggin' alien or summat - lol.  Has ANYONE in the UK managed to get hold of the 'correct' grey tinted glass required for their cabs?

help!

[RandyT]

Also I assume that tinted glass will cut down on reflections?

I would think that it would actually make it worse. The darker it is the more mirror like it would be.

Ras2a gets the nod on this one.  Read on to understand why this is true.

Glass and other optical materials have a number of properties; Diffusion, Surface quality, distortion, reflectivity, transmission, absorption and index of refraction to name a few.   These can all be controlled to a certain extent by manufacturing processes and/or optical coatings.

The ones that we are concerned with the most are Transmission, Reflectivity, and to a lesser extent, absorption.

The reflectivity of a surface is pretty much a constant based on a material and it's finish.  You perceive the darker material to be more reflective because less *transmitted* light gets mixed with the *reflected* light and the reflected light is seen with less interference and is therefore seen more clearly.

A simple way to think about this for our purposes is:

% Transmission = 100 -  (% Reflectance + % Absorption)
% Absorption = 100 -  (% Reflectance + % Transmission)
% Reflectance = 100 -  (% Absorption + % Transmission)

So in plain English, the less a material transmits and absorbs, the more it reflects, and the less it reflects or absorbs, the more it transmits.

Regular *clear* window glass, has a reflectance of about 2% per surface, or 4%.  If that same glass were opaque (i.e.  0% transmission in the visible spectrum and essentially black to the human eye) then you could only get a reflection from one surface.  Therefore, a dark piece of optical material is actually *less* reflective than a clear piece.

So what is optimal?

Something very expensive.  If you can afford it, an AR coating (Anti-Reflective) would be essential.  The material itself should absorb light *evenly* across the visible band.  This is known as a Neutral Density Filter.  The percentage of light that is allowed to pass should start at about 32 and go down from there, depending entirely on the effect you desire.

But what is practical?

Something that does the job, without breaking the bank.  If you are looking at a very specific transmission, clear glass with a well-applied window tint may be what you want.  Plexi comes in a "light" and "dark" version.  It is also made by a few companies under different names, but it's all Acrylic plastic.  Most will have their own light and dark versions, but may differ by the color and how much light is transmitted.

Suggestion.

Get samples!  If you can get a small chunk, take it home and see what it does over your screen.  When you get what you want,  buy a bigger piece.

But if you want to hide your screen, 20% or less (the dark smoke acrylic is usually between 16% and 18%)  If that's not what you are after, try 30% or slightly above.  You may need to go with one type of material over another just to get the specs you are looking for, and there's always automotive tint as a last resort.

...and that's about all I can tell you.

RandyT

[darktemp]

I've found that some shops carry 1 type of smoked gray glass which they call "regular gray" (not real helpful), however some shops carry the regular gray along with "graylite".  At first I would have assumed that the graylite was a lighter gray and wouldn't work, after doing some research however I found this:

"Graylite is unique among all tinted glass, offering a dark-gray, almost black appearance which provides excellent glare control, shading coefficient and ultraviolet screening.  Available in two thicknesses:

        Graylite #31 (31% light transmittance) is 1/8" thick
        Graylite #14 (14% light transmittance) is 1/4" thick "

I had been calling around looking for a tint with a light transmittance around 20% as RandyT suggested but nobody had that information.  So I ask, is 1/4" graylite at 14% VLT the best glass to use or is it too dark?

[ras2a]

Wow, thanks for that Randy, you sound like a clever bloke who knows his stuff.  Nice one mate .  Also Darktemp, thanks for that...never heard of greylite before.  I have been told that you can get laminated glass and it's the laminate part that is tinted rather than the actual glass itself.  This sounds like a feasible option, but again, it's knowing what to use.  I think I'll just experiment a bit as Randy says, until I find summat that works for me.

thanks guys!

[keltech]

Another vote for glass here: I got a piece 599x642mm, tinted & toughened for

[Minwah]

I was just wondering where you got your glass cut cheap in the UK? have you any contact details please

I got mine from this place:

Witney Glass
Unit 1,
West End Industrial Estate,
Witney,
OX28 1UB

01993 771515

I know they don't do the cutting/tinting/toughening process themselves, they send it somewhere.  One thing I would say is that they cut it very accurately, from the measurements I gave them.

You might end up paying more with shipping costs etc. tho.  Personally I would probably prefer to get glass locally...

[psik0tik]

Just get regular clear glass (its cheaper) and pick up a roll of tint from the auto parts store for like 12 bucks. Its easy as hell to put on and that way if you dont like it scrape it off and try again. Also I think  they sell that stick on stuff too that peels right off. For oldskool you could probably pick up a really light shade of this stuff to darken up your glass some. I used this s tuff and it comes out perfect.

[tommy]

Its true there is only grey and bronze in most cases, it depends what the glass shop is mostly in bussiness to do.

If you buy 1/4 grey it will be slightly darker then 1/8, i dont like plexi at all it does scratch easy and over long periods of time exposed to sunlight it will cloudup.

I always cut my own glass when needed for the best possible fit.