Shelf life of anti fouling paint

[marshcat]

I have a five year old can of Woolsey Neptune II bottom paint. This is a water based paint, similar to Hydrocoat. Does anyone have any experience using older cans of bottom paint? The Hydrocoat data sheet does not say anything about shelf life, and Neptune II is no longer made. I am thinking that if I can still mix the pigment and copper thoroughly, than it is OK to use the paint.

Also, does anyone know the correct syntax to search the forum for a phrase? I tried enclosing "shelf life" in quotes, but still seem to get all posts that contain either shelf OR life. I could not find any suggestions in the FAQ.

Thanks,

Kevin

[Ian McColgin]

Original seal in tact?

If so, get a powerful stirrer on a drill press or get a boat yard paint shaker (hardware store and paint store units are not up the throw weight) to mix it up and have a go.

If it looks ok when mixed and goes on smoothly - no ropey or flakey - then enjoy.

[kc8pql]

I'll add that turning the can upside down and leaving it for a few days will make mixing easier if you can't find a paint shaker.

[Ian McColgin]

The paint stirrer I recommend fits a 1/2" drill chuck - won't get into a 3/8".

You'd be amazed at the momentum this process can build. If you must do this, dig a hole in the sand to put the pot half or further down, tamp it in, and only then open to start the stir. Get a comfortable low stool because it'll take a while. Start at a pretty slow speed and work your way towards the bottom slowly. I've brought some old cans back to life but it took a good 20 minutes and left me pretty tired.

G'luck

[marshcat]

The seal is not intact, but when I shake the can I can still feel some fluid moving around inside. I'll try leaving it upside down for awhile, then use the stirrer on my 1/2 inch drill. I can put the chuck handle back on to make it easier. Thanks for the suggestions.

[Ian McColgin]

Don't turn it over. It's amazing what bottom paint can get out of.

It may have skimmed over. Open it up. If there's a skim, carefully cut all around at the pail interior and pick it out.

Then stir.