Page 1 of 5

Need help fixing a cracked tank

Posted: Tue Aug 16, 2011 8:09 pm
by xvCODY
Ive talked about this in 2 other threads slightly but i figured id make a thread just about it. I recently acquired a 75g tank off Craigslist practically free because the end was cracked. What would be the easiest way to go about fixing this problem? Replace the whole piece of glass, fix the cracks, reinforce the glass? Needing some tips. lol

Here's the cracks.

http://i57.photobucket.com/albums/g224/ ... ack003.jpg

Thank you, anyone and everyone, for any future input!

Re: Need help fixing a cracked tank

Posted: Tue Aug 16, 2011 8:22 pm
by Black Widow
That crack is to big to reinforce!

Replace WHOLE GLASS is the only thing to do to ensure its strong enough to remain water tight

Re: Need help fixing a cracked tank

Posted: Tue Aug 16, 2011 9:19 pm
by xrayjeeper83
Ya the only way id feel safe is to replace the whole panel

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 10:17 am
by xvCODY
i figured id have to replace the whole thing. Is there an easy way to remove the black brace from the top of the tank?

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 10:24 am
by Black Widow
xvCODY wrote:i figured id have to replace the whole thing. Is there an easy way to remove the black brace from the top of the tank?
Nope just a razor blade, and slowly slicing away the silicone

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 10:30 am
by bertie 83
You got quite a project there. As stated above chop out silicone with a razor, clean the edges to be resealed of silicone also. Good luck

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 10:33 am
by xvCODY
Right on. ill keep you all posted. this wont be fun with one hand. lol

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 10:40 am
by J-P
it can be done, BUT a pain in the a$$.

The trim is easy to remove.
tankcrack003b.jpg
It MIGHT be possible to laminate a sheet of acrylic to it both inside and outside. That will certainly HOLD. The downside of that is the acrylic is more heat absorbant than glass and will expand more readily.

You'd have to cut the outside acrylic to the exact size and silicone all the cracks and seams and adhere the outside pane. The inside pane should be cut only to the edged of the corner silicone. Adhere it the same way. Then re-silicone the the corners and bottom in question.

That is the cheap and easy and not guaranteed 100% to work way ;)

P.S.
I laminated the inside of a glass tank with acrylic in a similar fashion. Once the tank was brought up to temp the crack grew BIGGER because the acrylic expanded. I was lucky because the acrylic was thick enough to take the pressure. This will not always be the case.

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 11:10 am
by xvCODY
im thinking the hardest part will be to remove the trim, imo. removing/replacing the panel wont be too hard

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 11:13 am
by J-P
feel it with your fingers on both the inside and the outside. You can slip the exacto knife under and wedge it along. The top will still be held to the tank but with the sides cut away you can start folding it back and cutting that portion also.

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 3:18 pm
by xvCODY
Is there anyway i could heat the tank to get through the silicon faster? maybe with a hair dryer?

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 3:44 pm
by Arny
xvCODY wrote:Is there anyway i could heat the tank to get through the silicon faster? maybe with a hair dryer?
Why don't you use silicone remover. You apply it to the silicone and leave it for a bit and the just scrape it off with a razor blade

http://www.ebay.co.uk/itm/NO-NONSENSE-S ... 35b2c1c900

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 3:55 pm
by xvCODY
the trim around the top is almost 2 inches tall. Its just difficult to get the blade all the way up in there and to cut the silicone. Im just being impatient i guess, lol

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 4:28 pm
by bertie 83
Yes, have a break, look at the tank and what you can do when complete. Then take a deep breath and start again

Re: Need help fixing a cracked tank

Posted: Wed Aug 17, 2011 4:43 pm
by Black Widow
Why dont you heat the razor til red hot then melt thru the silicon bit by bit