Polycarbonate

[Meche]

Anyone have any thoughts on polycarbonate for use in a marine environment? Price is no issue. I think is is slightly less rigid than acrylic but I know it is stronger. Has anyone used polycarbonate on a project before?

I'm going to start working on finding youngs modulus, yield stress, and yield strain for glass and acrylic to see how they compare.

PC
Young's Modulus = 2400MPa
Yield stress = 65-67MPa
Yield strain = 6.2-6.3%
Light transmittance 89% @ 2mm, 88% @ 3mm

 

[jsmkmavity]

it is not as clear and it absorbs water

 

[IAP Brian]

it is not as clear and it absorbs water

Yeah, what he said. In addition to that it is a lot more flexable than cast acrylic. Look at it's coefficient of deflection ratio. I have not built any tanks out of polycarb (or extruded) but I have seen tanks built from both. All most every extruded tank that was not a cylinder blew out within 2-3 yrs. The poly carb tanks bow really, really bad. Lanzo at Aq P, has/ had some up stairs and they look like crap. They were 1/2 and 3/8 thick 75 and 90 gal tanks and they looked like footballs. They were also very yellow.

Basically I would advise against polycarb or extruded for tank construction. That material makes a better lid than tank.

 

[Meche]

They were 1/2 and 3/8 thick 75 and 90 gal tanks and they looked like footballs. They were also very yellow.

I still might buy it, just not use it for the "el grande project". I found a lot of it for $50. The lot has 1 4'x8' sheet and many "scraps", wich are feet x feet. I figured I could buy that and make a tank for what it would cost me to buy enough acrylic for my sump baffles.

Maybe I'll just make the baffles and sell the rest on ebay. :lol: