Primarily Petroliana Shop Talk Forums Shop Talk Petroliana Forums General Petroliana Discussion Lexan sign repair????

I bought a Standard Oil sign at Rex's sale and the lexan is cracked. My question is what can I use to glue the cracks back together. I am going to display it when I am done so all suggestions welcome.

Thanks, phil

Phil you can use model glue if it is not going to see the weather. If it is outside try some clear liquid nails or silicone. You dont want it to show up bad when you lite it. You could also call a local sign shop to see what they recomend.

Hey Phil,

First off, it's probably not Lexan (polycarbonate). Lexan typically does not crack unless under extreme low temperatures. It's most likely acrylic (polymethyl methacrylate), which stands up to weather (UV) better than Lexan, but is brittle and prone to cracking. Just a guess.
If it is acrylic:
Bonding agents exist for acrylic, both for its biomed uses as well as in manufacturing.

A quick search of the web, though, shows that the most promising and affordable looks like Ambroid Pro Weld, seen here: http://spruebrothers.zoovy.com/product/AMD110XXX?META=froogle-AMD110XXX

If you think it's Lexan, though, this will not work and you'll want to try something else in the hobby industry.

Try not to get it on the exposed front surface.

If you do, you may end up having to wet sand and plastic polish, which I know you don't want to do, because then you'd have to do the whole thing.

Good luck,
Wes


[This message has been edited by thermactor (edited 02-03-2006).]

A guy named Lance gave me a good tip, apply glue from the display side, it will wick thru and the mess/cleanup will be on the unseen side!

Wow Wes,

Great reply. Thanks to you Brad and dodo. I tried a local sign shop and they brushed me off so I thought I would ask the experts. I did not know that there were nuclear scientists on this site (Wes)

Thanks to all,

Phil

Nuclear scientist? I wish... No, just a lowly engineer.

Wes

No kidding Phil. I cant even say the words & he is spelling them & giving the definition to them

I have used cyanoacrylate bonding agents very successfully on all types of plastic - especially Lexan and PMM acrylic.
Cyanoacrylate is what "Krazy Glue" is made of - but don't buy or use Krazy Glue! It is a very low-grade product, full of stabilizers and fillers.
Go to a model airplane shop and buy "Thin" cyano glue to seal a crack. This stuff will wick into the crack and if you get lucky, you will barely be able to see the repair. It will definitely stabilize the crack.
This glue comes in several thicknesses. If you need to fill a bit of a gap, get the medium or thick.

Be very sparing with your application of the glue. It dries clear, but if you use too much, it dries whitish, and can "fog" surrounding surfaces when it "goes off" - cures more or less within 5 minutes or so.