[BLUESMAN]

OKAY I HAVE TRIED TO DO THIS TWICW NOW WITH THE LEXAN NOT SEALING TO GLASS.IS THERE A SPECIAL EPOXY THAT WILL WELD THESE TWO PIECES TOGETHER? AND WHERE CAN I GET IT?PLEASE TELL ME AT HOME DEPOT.THANKS.

[icemark]

Lexan is tough to bond to anything that is not plastic. You might be able to use GE Silicon glue, with a good amount on each side. Make sure you don't use silicon 2, and you clean the surfaces well.

BTW: All caps suggests that you are yelling.

[BLUESMAN]

Sorry for the locked caps.I guess i should of made my problem more clear.I am trying to weld a 48" (1/4") lexan to the back of my 55g.I shattered it drilling for a bulkhead.The two for my 80g went fine.I was thinking that the 55 had too thin of glass.Back to my problem of welding lexan onto glass.Any ideas????

[icemark]

I would still use the GE or dupont silicon glue

[organicreefer]

to fix a glass tank you need to use glass and silicone.

[MarkS]

Originally posted by organicreefer
to fix a glass tank you need to use glass and silicone.

Yep. Silicone will peel right off of plastic under that much pressure. I cannot think of any glue stronger than epoxy and you tried that without success. Apart from that, Lexan is much more flexible than other plastics by design. This IS NOT what you want to construct a tank out of.

Mark

[organicreefer]

also before you can repair the crack ,you must force it out to an edge,if this is not done the water pressure will do it when you refill it.after you have forced the crack out to the edges you can cut or break peices of glass (of the same thickness as the tank)and cover the crack spread and fill with ample silicone and walla!ugly but funcional.hth

[BLUESMAN]

When I drilled the glass the whole sheet shattered...so replacing the whole piece was the only option.So I tried Acrlic since I knew I could drill it.I have tried again this weekend to use the epoxy after I sanded the glass and acrlic.I have just finished siliconing so I will see if this works.I"m not too confident that this will work and that case I will be do one of three things.....1)buy another 55 and hope I can drill it,2)buy a 80 and know I can drill it,or 3)Build an tank from Acrylic(24" x48"x24"deep.The 55 I can get for $80,80 for $150,or the built tank for $100.I'm very unsure that I can build a leak proof tank at this point .What do you all think?

[organicreefer]

im going to say ,since its the back that is broke,i would go ahead and buy a new one.sorry to say that but i think youll save alot of time/money/and frustration if you just cut youre loss.

[David]

Bluesman- There is a product called "Lexcell" that claims to bond acrylic to glass. I know for a fact that it bonds glass to fiberglass because I have used it, I just bought some more to experiment with the glass to acrylic bond. It is similiar to silicon but a little more difficult to work with. You could always use 3-M 5200 but it does not come in clear, only black or white. I am curious to know how you are drilling glass. I have had some success with Lenox "Grit Master" hole saw and silicon carbide grit but the bits wear out after two holes. What is your technique? If you are replacing entire back panel why not use glass? Drill it first and then silicon it in place. Oh yea, Lexcell is labeled "not for use in aquariums". I called manufacturer, the reason is cure time. After a week or two it is totally inert.

[organicreefer]

by replacing a whole panel youre just asking for leaks.when a tank is constructed,it has to all be silconed at once to form a seam all the way round. a cheap glass 55 isnt worth the risk imo.
i have drilled three tanks so far,four holes total,with a tile hole saw from hd

[icemark]

Lexan is also very flexible, you would be much better using acrylic if you had to use a plastic.

Everyone is right though, you should be repairing that cracked panel with glass not plastic.