Acrylic Letters to Cement Face

[joshGN]

Im installing 3/4in and 1/2in acrylic letters to a painted cement outdoor monument sign.

The 3/4in letters are 9.5in tall and the 1/2in letters are 5.5in tall....Not stud mounted.

What would you suggest for adhesive?

I was going to use VHB and silicone....thoughts?

 

[Billct2]

VHB and Lexel

 

[bjt140]

Scibond 45 is a good one. Not sure if it's rated for outdoor use, but after an hr it pulls chunks out of our granite if we try to separate it.

 

[visual800]

a lil bit VHB (to hold) and silicone should be fine

Scuff the back with a low grit paper and clean with alcohol to give silicone a bite

 

[T_K]

Scibond 45 is a good one. Not sure if it's rated for outdoor use, but after an hr it pulls chunks out of our granite if we try to separate it.

That sounds great, until they're ready to replace the acrylic letters. But it's concrete facing, so I guess patching is always an option.

 

[joshGN]

Thanks for the suggestions.... I used VHB and Lexel...came out great!

 

[a77]

a lil bit VHB (to hold) and silicone should be fine

Scuff the back with a low grit paper and clean with alcohol to give silicone a bite

Have you ever had an issue with crazing/cracking when using acohol to clean? I have and now I try to not use high concentration isopropynol.

 

[Moze]

Thanks for the suggestions.... I used VHB and Lexel...came out great!

Looks good.

You kicked the light, didn't you? lol.... (kidding, but I've been there...)

 

[Moze]

Scibond 45 is a good one. Not sure if it's rated for outdoor use, but after an hr it pulls chunks out of our granite if we try to separate it.

Lexel is about the best you can use for outdoor use - especially with acrylic. It eats into the acrylic. In fact, maybe not coincidentally, it's like when you would assemble models as a kid - the model glue would eat into the plastic pieces. That's what this does. It also smells exactly like model glue. They must have similar ingredients.

 

[Gino]

I really like happy endings.​

 

[Chuck Peterson]

Lexel is a great product. I don't know why anyone would use silicone on a job where they really need to be extra secure.

 

[visual800]

Have you ever had an issue with crazing/cracking when using acohol to clean? I have and now I try to not use high concentration isopropynol.

no sir havnt had an issue and never use on the front

 

[FS-Keith]

Lexel is a great product. I don't know why anyone would use silicone on a job where they really need to be extra secure.

I have yet to use lexel but look forward to trying it. I use silicone without any failures. In fact a couple years ago i was removing a 17' long channel letter raceway from a building about 50' up that i had only installed a year prior. We make a habit of putting a ring of silicone around the power hole on the backside of signs and along the top of the signs so water does not run down the back. We had taken all the fasteners out and had to use a 3' prybar and the weight of 2 guys in the basket to break the seal of the silicone behind the sign. Silicone works really well in diff applications. I am going to try the lexel and the sikaflex on a job soon thought because I always see everyone raving about it here.

 

[Moze]

Silicone works great for non-acrylic and non-polycarbonate applications. For those, Lexel is the best. It's the only adhesive I've found that specifically lists those items.

I posted this a while ago, but this is a picture of an acrylic panel that was adhered to concrete that had to be replaced.

On the flip side, I've removed acrylic signs from walls and could peel the silicone off like that gummy stuff they attach credit cards to paper with.

All of that being said, most sign companies still specify silicone in their drawings and some actually provide me with the tubes they prefer to use. Not my preference and typically smaller room ID signs will be fine with it. But if there's something exterior or with some weight to it, I'll use Lexel.