look what i found....

[bagedtaco]

true.. but i'm not bonding(chemical bond) the acrylic to the glass.... i'm just forming the same glue joint that silicone and glass would have. not a acrlylic to acrylic bonded joint. remember that large tanks that use acrylic as it's viewing area and plywood or other materials as the sides use silicone to glue and form a water tight seal.

a glass on glass joint with silicone is as strong as a glass on acrylic with silicone.

i'm not sure if weldon 40 will bond glass and acrylic. i've never tryed it.

 

[clutch]

I had to do the same for mine. my glass came right out.You have to clean the glass very good the adhesive will cure to glass proper.
http://reefcentral.com/gallery/data/500/77230210top.jpg

I phoned oceanic if I could put two small braces and they said it would ruin the integrate of the aquarium(wouldn't recommend it)

I was bummed. So I run lights on either side of brace and leave the middle for vho's. MH are too hot for glass esp. 400w I would say that what happened to crack.

 

[jay24k]

Acrylic and silicone is not as strong as a join as silicone on glass just to let you know. I think that is what people are telling you. Silicone does not adhere as strong to acrylic. Therefore that brace up top will not do a dang thing for support. You might as well just remove it IMO. Or use weldon that works for acrylic to glass.

 

[bagedtaco]

ok... thanks

i'll look into the weldon.

 

[Crusty Old Shellback]

There is a silicone that is MADE for use with Acrylic. Home Depot sells it. Works good.

 

[bagedtaco]

63chevy... do you know what it's called??

 

[lfjewett]

Hey bagedtaco, the silicone advice given is accurate. You can silicone Acrylic to Glass in non-structural applications. Perfect examples of this are as baffles in sumps where the force on each side of the baffle is near zero. Large plywood tanks do not count on silicone to adhear to the Acrylic but rather the pressure in the tank to create a gasket out of the silicone.

Both silicone and glass are made of silicate and theirfore they will bond at the molecular level. Your joint has the same tensile strength as the silicone itself. Ever notice even with a razor blade you can never get "ALL" the silicone off of glass?

Silicone will adhear to Acyrlic but will not "bond" with it. Theirfore the strength of your joint is limited by this adhesion.

Honestly your very best bet is to replace the brace with silicone and glass as suggested earlier.

The second best option would be IPS Weld on #15 I believe as this is the only Weld-On I could find that listed glass. Reference is this page HERE ..

Good luck!