what material for lighted sign

[technowolf]

Hi guys,

I just got my first lighted sign job.... a 44'' x 94'' double side neon light box.
I know how to do the install and all but dont know what kind of plexiglass to use or thickness?
There will be no printing only cut vinyl but what kind of oracal vinyl must i use?.... and do i aplly direct on plexiglass??

thanks for helping

Alex

[andy]

Plexiglas panels should be 5mm thick for this size. Depending on how your box is built handing strips on the back of the Plex which allow it to "hang" inside the box framework will help to eliminate bowing and warping when the Plex gets hot/ cold.

You need an Opal White Plex- we standardise on 050 (50% light transmission).

You should ALWAYS use proper translucent vinyl for illuminated signs- lot's of people slap on standard vinyl BUT translucent gives you a proper colour tone when illuminated PLUS it makes for a much better looking sign.

You can apply vinyl straight onto Plex- rip off the cover sheet, give it a quite whipe with IPA and you are good to go.

[imaSIGNr]

Neon ?

[technowolf]

Andy thanks for the tips

but you say ''framework will help to eliminate bowing and warping when the Plex gets hot/ cold.'' what kind of frame work you talking about?

[andy]

In the UK all our illuminated sign cases are made using specially designed aluminium extrusions- you just cut to size and assemble.

These extrusions are shaped to allow you to slide Plex panels into the box once you have made it up. Part of the extrusion allows for a 12mm deep offcut strip of Plex to be bonded onto the back of the Plex panel flush with the top edge.

If you use the hanging strip method you undercut the Plex panels so that they don't touch the case/ frame on either end or the bottom. As a rough rule of thumb you under cut the depth by 10mm and the total length by 10mm. (this varies depending on how big your panels are).

Once you slide the Plex panel into the frame the hanging strips pick up the panel and support it on the case extrusion. This means that the panel weight is supported from the top by the hanging strips.

With an under size panel supported from the top by hanging strips your display panels "float" inside the sign case- allowing the panel to breathe.

A good move is to ask your Plex supplier for a workshop manual- not a sales manual. In the workshop manual it will tell you by how much a sheet of Plex of a given thickness will expand when it gets hot. This movement when the plex heats up on hot days and shrinks back on cold nights is the reason why some illuminated sign panels look warped.

On large panels without hanging strips all the weight is simply resting on the bottom of the box. Once the panel gets hot and starts to expand (which all acrylic does) the expansion has no where to go and the panel starts to warp.

Another crucial reason for using hanging strips is that they help to secure the panel inside the frame- an unsupported panel is at more risk of wind loading- panels can either be blown in or sucked out on windy days.

If you are working with a case that does not allow for hanging bars I always used to take of the top frame trim and screw the Plex onto the case through oversize holes- this allows the panel to "hang" and also helps to secure it inside the casing.

You are lucky because the size you have means you won't need a join between two sheets of plex which will make your life a lot easier.

The Plex manual will also have information on the panel thicknesses recommended in relation to how deep your sign is- I said 5mm as I know it has worked with no problems. On a 44" panel you may well find that Plex recommend an 8mm panel (but that causes problems with weight). Plex panels need thicker material the deeper they are.

Google a Plex workshop manual- the German Plex site has a stack of good info. If not try Perspex (same stuff as plex just different name).

[Techman]

lot's of people slap on standard vinyl BUT

Those that cheap on this by using regular vinyl need to be punished severly. IF they cannot charge the amount needed to make a profit using the proper materials shouldn't be in the bizz.

[technowolf]

Thank you Andy for taking the time to explain the wonderfull world of plexi sign, that was super good info.

Alex

[technowolf]

how much should I charge for 1 signs like that 44'' x 94'' double side whit install. the layout is split in half for 2 customer.

Alex

[Gino]

On 3/16" modified acrylic and that's not a metal divider bar, only vinyl... around..... $1,600 + installation.


Make sure you have the correct dimensions, because you don't want to make the sign too snug and it bows out in the summer. Give yourself a good 1/4" all around whether it's a hanger or a slide in.

[technowolf]

thanks for the tips Gino