3/8" acrylic for lids?

[robham777]

I salvaged some 3/8" x 5" x 4' acrylic strips thinking they might make good aquarium lids. I have some weld on 4 to cement them together, but was wondering how badly they would bow before taking the time to cut them, prep them, and cement them. The largest unbraced span would be around 30" and if not good for lids any suggestions of possible uses.

 

[aotechs]

I put two sheets of 1/4" on a 40 breeder and have to flip them over every two weeks to keep the bowing to a minimum. If you plan to drill holes in it, keep placement in mind for when you have to flip it.

 

[paulW]

They will warp. You might want to glue a few strips of acylic perpendicular to the lid to help.

Sort of like this picture. See how he has two pieces of acyrlic glued at 90 degrees.. put bracing like that around the lid.. Also gives you a handle to lift the lid.
http://melevsreef.com/pics/12/2/acclimation_box_open.jpg

This helps on soild sheets of plastic used as lids (They will still warp a little though).
Not sure if it will help when the lid is strips glued together as you plan to do.

 

[Drstrangelove]

Acrylic in the presence of heat and moisture tends to warp. Obviously thicker is better and warping can be corrected to an extent by flipping regularly, but that would be a pain to me. Over the long term, I just don't see it staying consistently flat over it's entire surface as something like glass.

 

[robham777]

Thanks for the input guys. I ended up using polycarbonate for now. I may use the acrylic to build some overhead filters at some point. It would be nice to get a little hands one experience working with free acrylic scraps before attempting any large scale projects.

 

[squint]

I use polycarbonate as well. They're only 1/8" but have held up well.

One material I've been meaning to try is Coroplast.