BIG Adhesive Question

[Bebe]

Here's a tricky one. I need to "affix" four pieces of fused glass that weigh approx. 14 - 16 lbs each to an 8' circular window that is exposed to the elements. My concerns are clarity, flexibility, etc and not killing someone walking in the door under this thing. The client wanted a domed appearance to the glass, but I had to nix that idea due to weight if it were cast, and heat/moisture underneath if it were slumped. So I'm going for flat for more surface to adhere. CR Lawrence recommended a water clear silicon or a loctite product. But they suggested I TEST it first -which doesn't instill a lot of confidence!

I've considered etching the back of the piece for more "tooth" if I use the adhesive, but I hate to lose the clarity of the glass. Is this necessary?

My alternate thought was to drill holes in the fused piece, match it to holes in the window, have all the pieces tempered and then assembled with bolts - AND the adhesive.

Has anyone ever done this? Does anyone know of an engineer who can tell me the technical data on weight/strength etc?

And now - what is my liability? Thanks, guys. I know this is a lot to ask!

[ellen abbott]

In the mid-80's, we did a commission that had 21 different fossil forms cast in clear Blenko crystal glass and glued onto the surface of the panels. They ranged in size from about 8.5" diameter x 2" tall (smallest) to about 13" x 10" x 3" tall (largest). We used a flat lap to finish the bottoms and glued them on with 2 part epoxy. the epoxy 'cleared up' the bottoms that were glued onto the clear glass. Not crystal clear, I'm sure since the forms themselves were very textured and were not crystal clear. 20 years later they are still on there. Granted, this was a ground level installation and nobody was walking underneath it.

E

[M.L.]

I use UV6800. It a silicone based adhesive, doesn't yellow. I have used it and haven't had a loose piece yet. Then again have only used it for 3 years. Comes in a 10oz. caulk gun tube, and a 4oz squeeze tube. I get it from Adhesive Plus (972) 422-2180. They are out of Texas, apparently they manufacture it, and can't find it in stores, at least not here anyway. Good luck. Mike

[Barbara Muth]

I definitely would go for a silicon adhesive. My plastics guy has used silicone in the construction of signs. Somewhere in Maryland is a hospital sign outside, that he made 25 years ago, all glued up with GE brand clear silicone that has never needed any repair despite its exposure to sun, cold, wind and precipitation.

Your liability is a different question. My answer is, I don't know.

Barbara

[Carol Craiglow]

Bebe....is there anyway you can put an unobtrusive thin steel lip/shelf below the pieces to provide some support?

If you could do that and then have the pieces kind of stack on one another, along with silicone, that would be what I would do.

As one who had a ceramic mosaic bas relief sculpture of the world slide off en masse and partially hit a woman in a wheel chair who was window shopping (she wasn't injured thank God)....I would be very careful about gluing anything above people!

In my case, it was outdoors and even tho I had researched adhesives extensively, apparently moisture got thru the grout (even tho it was sealed) and beneath the silicone and one particularly cold night in Colorado caused the water to freeze and expand, breaking the bond between the silicone and the substrate, and then all of the mosaic pieces and grout slid off the next day when it thawed.

So, I'm not sure if yours will actually be outdoors, or if the pieces will be on the inside....that of course would make a difference....but lesson learned for me is - you can't be too careful!

[Carol Craiglow]

Bebe....is there anyway you can put an unobtrusive thin steel lip/shelf below the pieces to provide some support?

If you could do that and then have the pieces kind of stack on one another, along with silicone, that would be what I would do.

As one who had a ceramic mosaic bas relief sculpture of the world slide off en masse and partially hit a woman in a wheel chair who was window shopping (she wasn't injured thank God)....I would be very careful about gluing anything above people!

In my case, it was outdoors and even tho I had researched adhesives extensively, apparently moisture got thru the grout (even tho it was sealed) and beneath the silicone and one particularly cold night in Colorado caused the water to freeze and expand, breaking the bond between the silicone and the substrate, and then all of the mosaic pieces and grout slid off the next day when it thawed.

So, I'm not sure if yours will actually be outdoors, or if the pieces will be on the inside....that of course would make a difference....but lesson learned for me is - you can't be too careful!

[Bert Weiss]

Liquid resin for laminating glass, preferably a low contraction formula. Zircon or Bohle make them.

Or 2 part liquid silicone.

I never used the silicone. The laminating resin requires VHB tape surrounding the top piece with 2 holes, one for the resin to go in and one for the air to go out. I would reinforce the tape with silicone around the perimeter.

[Tom Fuhrman]

I'd suggest VBB type adhesive from Tangent Industries, Winsted, Ct. I've got 4 fountains that are in a museum in Nashville that have been outside for 3 years with water on them and weigh over 85lb. a piece just glued onto a flat sheet of granite and stuck on a vertical wall. It is a silicone based polymer that cures with UV. as far as the liability, Chihuly made his ceiling at The Bellagio in Las Vegas from plastic because of the liability issue. Does that tell you anything. I would make sure that the panel I was adhering it to would be a laminated piece so that it would not break and you wouldn't have any sharp spearlike pieces coming down on anyone. Tenn. Tom http://www.fuhrmanglass.com

[Bebe]

Thank you all SOOOO MUCH for all the good advice! I will take the unanimous vote and go for a silicon adhesive with bolts. And I didn't know that the Chihuly ceiling at the Bellagio is plastic! Wow! There is a never-ending source of knowledge from this board!

Thanks again for your input!
BEBE
PS. If I get the commission I'll post pictures!

[Bert Weiss]

Thank you all SOOOO MUCH for all the good advice! I will take the unanimous vote and go for a silicon adhesive with bolts. And I didn't know that the Chihuly ceiling at the Bellagio is plastic! Wow! There is a never-ending source of knowledge from this board!

Thanks again for your input!
BEBE
PS. If I get the commission I'll post pictures!

I've heard there was plastic involved but it did look like glass to me. Who knows for sure how it was done?

[shesh46]

I would try hexdoyl it is a two part epoxy.

[charlie holden]

I've heard a different story about the big Chihuly stuff. From what I understand, the big, exposed towers and chandeliers were originally glass with a plastic coating on the inside. More recently they have been blown from plastic. The huge, blue towers that sit on the bridge over the freeway at the Museum of Glass in Tacoma are definitely plastic. You can see the seam lines when you stand below them. They are also just slightly dull.

But the overhead stuff that is placed on top of float, I think, is all glass. I would imagine that the float is tempered and laminated which would cover the liability. The pieces in the ceiling on the Tacoma bridge looks distinctly more like glass than the towers do. I don't know how the ceiling at the Bellagio is laid out, so I don't know if it is on float or not.

ch

[Bert Weiss]

I've heard a different story about the big Chihuly stuff. From what I understand, the big, exposed towers and chandeliers were originally glass with a plastic coating on the inside. More recently they have been blown from plastic. The huge, blue towers that sit on the bridge over the freeway at the Museum of Glass in Tacoma are definitely plastic. You can see the seam lines when you stand below them. They are also just slightly dull.

But the overhead stuff that is placed on top of float, I think, is all glass. I would imagine that the float is tempered and laminated which would cover the liability. The pieces in the ceiling on the Tacoma bridge looks distinctly more like glass than the towers do. I don't know how the ceiling at the Bellagio is laid out, so I don't know if it is on float or not.

ch

I am easily ready to believe that the ceiling pieces at the Bellagio have a clear plastic lining that would prevent them from shattering and falling apart.

I saw the bridge a couple of months ago and didn't get the impression that they were not glass. How could the museum of glass have plastic for it's signature pieces??

I've seen the technique used to blow the big shapes in glass. I'm reaching in to my mental storage area for the artist's name who did some seminal work in this area John... He is a comedian / artist from NYC. The work he did at Pilchick as visiting artist utilized 2 part plaster blow molds. The gaffer would get the glass to a point, heat it well, place the bubble in the blow mold and blow the glass out to fill the mold. The molds used when I watched were very large cut crystal gemstone shapes. (bigger than a foot in diameter as I recall them) When I was at the museum, I recognized the technique. The somewhat dull surface comes from contact with the plaster molds as opposed to most blown glass which is fire polished. The seam comes from the interface of the 2 part plaster molds. The plasters were affixed with hinges and long handles that clamped shut.

I certainly hope I am right on this one.

[Brock]

The artist is John Torreanno, but I've heard also, (but don't know for sure) that some of the work at TMG is indeed plastic. Brock