what material for underwater and impacts?

[knight_toolworks]

got an email from a place that does a lot of plasma cutting they do it in a tank of water and they want to protect the bottom of the tank from falling metal. they were thinking marine grade plywood. but I am thinking sintra would hold up better or a polypropylene sheet. the panels are about 4x8 with holes to fit over the pegs

[paul_z]

I'd try the polypropylene.

Paul Z

[knight_toolworks]

or abs I could not think of it. more work to cut and weighs more but this would be a very good job to get. I wonder if either float?

[steve_g]

Just threw a scrap of ABS and UHMWPE in a tank of water... the PE is floating, the ABS is on the bottom. Surprised me I thought they would both float.

SG

[shilala]

I'd think stainless grating, or some other thick, rustproof expanded metal.
I immediately thought aluminum, but I'm not sure exactly what your coolant/water reservoir looks like.
I'm not sure if the tank water recycles to the plasma head, but I'd be concerned about wood or plastic chipping and plugging nozzles.
Just thinking out loud, Steve. I don't know enough about what you're dealing with to be any help, really. :)

[gerryv]

I did a project with marine grade plywood that soon turned very, very mushy. The distributor told me that the glue was waterproof, not the wood, so the plywood is not "waterproof" per se. If structural integrity is an issue I'd not use the plywood. It also wants to float.

[knight_toolworks]

I don't know the details really it is not my tank. But they want the bottom mild steel tank protected from dropped metal and slag. abs seems perfect as it will just dent when it is hit. They are looking at 100 4x8 sheets so it is a big machine.