Impervious paint

[Anscojohn]

Hello All,
I have just completed cutting some floating lids for my one gallon tanks. They are cut from just plain old pine. I need to paint them with a paint that is totally impervious to developer, stop, and fixer. Any recommendations or suggestions?

 

[keithwms]

How about cutting your lids from delrin. I doubt you will ever find a paint that is impervious to the pH swings of the development process. Resin, maybe, but paint- I doubt it.

How about polyurethane.

 

[Mike Wilde]

consider fibreglass resin? I know it is messy, but my home made sink is still viable after 25 years of use.

The other option may be epoxy paint. I know it was used as a precursor to the now common powder coating for steel, and was used on school class room doors, etc. Small quantities may be hard to come by.

 

[Anscojohn]

Hmm, from what you all say, I might just reconsider and try to find a different material. Thanks for the information.

 

[Mick Fagan]

John, many years ago we manufactured some floating lids out of pine, to seal them we had them dipped into plastic, once dried and cured in an oven they were brilliant.

There was a downside though, the plastic coating made them a little heavy and they sort of floated slightly under the surface.

We had them coated with the 1.5mm thick option, the technicians after noting the sinking floating lids, realised we should have used the thinner 1mm coating option.

Still, they were in constant use in the lab for at least a year, until we put in a new replenishment system.

Mick.

 

[srs5694]

I seem to recall seeing a can of stuff intended to create a rubbery coating on objects, like the handle on many pliers and similar tools. You could try cutting a lid a little smaller than required and then covering it in this stuff. OTOH, it might be simpler and cheaper to just switch to some variety of plastic. IIRC, I saw this stuff in a Lowes store.

 

[removed account4]

consider fibreglass resin? I know it is messy, but my home made sink is still viable after 25 years of use.

The other option may be epoxy paint. I know it was used as a precursor to the now common powder coating for steel, and was used on school class room doors, etc. Small quantities may be hard to come by.

fiberglass resin is great stuff!
my sink was wood coated with that,
and it worked very well ...

 

[mgb74]

If they're untreated pine, and are not moved between tanks, do they need to be treated at all?

 

[John Koehrer]

They'll eventually saturate. With stop bath probably disintegrate over time.
some of the big box hardware have plastic by the sheet. It's not plexi or acrylic but a thick(1/4"?) black plastic that could work out. You might find something online too.

 

[Bob-D659]

Epoxy marine paint will work. The liquid electrical tape will work too, it might be cheaper to get some sheet plastic tho. HDPE pail lids will float, see here

http://www.machinist-materials.com/comparison_table_for_plastics.htm

used ones from pails of laundry or dishwashing detergent are cheap too.

 

[GeorgesGiralt]

Hi John !
I've a tank to store my stock developer. It is made of tubular PVC (used in water pipes). During one filling, the floating lid fall and as it was old and brittle it broke.
I used a sheet of 1/2 inch insulation plastic to make a replacement. Poly something. (it was a left over from roof insulation) it was easy to cut with an X-acto knife, floats well and was cheap ....

 

[John Koehrer]

Hadn't thought of using insulation. The stuff I had in mind was more rigid. But it makes perfect sense. The insulation doesn't have to have any real strength it has to float & keep the air out. Since it's easier to work & easily available it's a great idea.

 

[DWThomas]

Don't know how large a piece you need, but we have some plastic cutting boards in the kitchen that are about 5/16 inch thick and (barely) float. They seem like a pretty solid material; they are an opaque off-white, not the ones that look like textured glass. Check out your handy kitchen gadgets store.

DaveT