Painting an old Stainless Steel Purex 60 SqFt Filter

[Moondoggy]

I have a small pool service and a customer does not want to buy a new filter and just wants me to replace the grids. She wants to paint the filter when I am done. Is it safe to paint an old Stainless Steel Purex 60 SqFt Filter that looks ugly and has rust stains all over it?

What kind of paint (Oil base, Latex, or ?)

I think I heard somewhere that it is not ok to paint over something with pressure in it because it could cause it to explode. I don't remember were I heard this or for what product the discussion was about but I thought I should ask before cleaning up the old filter and letting her paint it to make it look better.

Thank you,
Happy Easter,
Moondoggy

[PoolDoc]

Painting won't cause it to explode! I can't even imagine what was going on in the mind of whoever originated that idea.

On the other hand, paint won't fix spots weakened by rust -- I'd recommend explaining that in writing to your customer and getting them to sign off on it. If the rust is nearly through the shell, it's likely (if you have my luck) to start leaking the week after you get it painted and all put back together. Customers in that situation tend to expect that you -- the service person -- have some obligation since "you just worked on it!". Explaining it in writing -- ahead of time -- and getting them to initial that can save your . . . 'rear area'.

As far as what paint -- any light color that will adhere well to metal is fine. To paint stainless, you'll probably need to go over it with a Scotch pad and detergent or TSP first, and then use a primer. Otherwise, there's a good chance it will start peeling off rather quickly.
Epoxy pool paint would be very durable, but is not usually UV protected and will 'chalk' over time.

[kelemvor]

Painting won't cause it to explode! I can't even imagine what was going on in the mind of whoever originated that idea.

I suspect it comes from information about painting significantly pressurized metal canisters. Specifically SCUBA tanks that typically are filled to about 3000psi. Some painting techniques heat the metal which can weaken it. Obviously not a significant concern with a filter that's going to hold 100psi or far less. Also, I doubt OP is talking about bake painting the filter.

[PoolDoc]

OK, that makes sense. Paint applied at high temps didn't even occur to me.