I work in the industrial chemical industry. I'm very curious to what bonding solution is inferior ? Weld-on ? IPS (i.e. weld-on #3) is one of our company's customer. :dontknow:
Wish I could answer that one for you. I'll ask and see what they use.
Im no chemist major, but just an educated Guess:
I'm thinking it's like comparing the different PSI strengths on silicon. Some aquarium High end glass aquarium builders use low psi silicone (I researched this). Industrial builders of Epcot and Seaworld use a higher grade silicone. I picked up a couple of those industrial tubes for myself and used them when I built sumps.
I know acrylic solvents melt the acrylic together to create one piece. So maybe it has something to do with how well it melts them together, and the strength the bond has made physically once it sets. :dontknow:
What I can tell you is what ever they use works well enough to hold these huge tanks together. Most builders I wont name, dont make large tanks, they hire PFI and mark up the price after they slap their sticker on the tank. Most of the guys on the group buy called other builders for quotes, the builders called PFI.
I'm thinking the reason a lot of people haven't heard of PFI is because they don't sell to the public directly. Places such as LIVING ART AQUATICS DESIGN are the ones who cater to clients such as Disney, Snoop Dogg, and so on. But the acrylic tanks are built next door at PFI.
See for your self.
http://www.aquatic2000.com/press.php
http://link.brightcove.com/services/player/bcpid1745089117?bctid=23201673001
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