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acrylic adhesives

Cynosure

New Member
Has anyone had any luck adhering acrylic standoff to a "used" acrylic water feature? I have tried weld on 3 & 16 and both failed within days of the water being turned on. The customer said the last guy used some kind of "white acid" that melted the pieces together almost instantly. Sounded like #3 to me.....no luck.
 

Moze

Active Member
If both pieces are acrylic, there's no reason it shouldn't hold. Sounds like you probably already know this, but the Weld-On cement acts the same as PVC cement in that it actually chemically welds/melts the two surfaces together. So the cemented part will typically become stronger than the rest of the material. If put under stress, it typically won't break at the cemented portion - it will break elsewhere. Anyway, point is, if the materials you're cementing are indeed compatible, the Weld-On should work fine. If it's not working....it would make me think you're dealing with different/incompatible materials.
 

Biker Scout

New Member
Sounds like a polycarbonate standoff to me. Besides that, you'd need a fresh, perfectly flat surface to work off of. One that has not been flame polished as well.
 

Moze

Active Member
Even with polycarbonate, he should be ok if using Weld-On 16 though.

Weld-On 3 should only be used on like-materials (acrylic with acrylic, polycarbonate with polycarbonte, etc.)

Weld-On 16 can be used on unlike materials (acrylic with polycarbonate, etc.). The Gemini pads (not sure if that's what the OP is referring to as 'standoffs') are cellulose acetate butyrate, which is one of the materials Weld-On 16 can be used on.

And not to be argumentative, but the Weld-On 16 allows for some irregularities in the surfaces. Some of the large Gemini pads can be pretty wavy and it works well on mounting those to flat surfaces.
 

Cynosure

New Member
They are custom, acrylic standoffs from Laird plastics. The backer board, I was told, was acrylic. It looks very warn, but there was a portion where an old standoff had broken away and it was shiny black like acrylic underneath.
Hopefully the attached photo will help.
 

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Moze

Active Member
Weld-On 16 Specs: Bonds rigid PVC, ABS, styrene, butyrate, polycarbonate to themselves and each other, as well as other plastics and porous surfaces.

Maybe that backer isn't one of those materials. Maybe there's chlorine or something in the water or embedded into the backer that's not allowing the cement to bond.
 

Biker Scout

New Member
Oh, that's a fountain? Yeah, water impurities and pitting are going to be a factor in getting anything to stick long term. I'd suggest using Lexel. Doesn't bond instantly, so you'd have to use tape to hold while it's curing, but should last way better, and it's not going to have an issue with water being present during the install.
 

Cynosure

New Member
The customer is against any kind of silicone type product like lexel as it is not a "weld" process. He is worried about "play" in the standoffs if we use silicone. The water is turned off during install and they left for 72 hours after install. I'm just stumped...
 

Biker Scout

New Member
It looked phenolic to me as well... but when they said it was a water feature, well, that could be from the calcium deposits. Either way, a tough way to mount something when having to work on site with a vertical surface, and deal with impurities.
 

Cynosure

New Member
So, if it is phenolic (honestly...no clue what that is), do we know of an adhesive that will work? I removed the old companies logo and they were mounted to it...so something works. The back walls were cleaned before installation, so the calcium buildup is gone.
 

Cynosure

New Member
Any reason you can't stud-mount them?

The customer does not want holes drilled into the back of the feature. Water cascades down from the top and they think eventually it will find its way through the holes and out the back of the unit, all over their marble floors.
 
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