As an admitted "hoarder of old paint" I simply keep them in the original containers. Keep them in a cool, dark place so sunlight and/or heat doesn't affect them. I have some cans of paint that are well over 20 years old. If I have a need to use paint that old, I simply pour it out through a strainer into another empty (clean) paint can, add a little Floetrol, mix well, and it's ready to go! It doesn't always work as some cans are more prone to rusty lids/lips and that can be problematic.

Also, if I do get a bunch of paint that I know I'll never use again, I pour the gallons into a five gallon bucket. Just be sure to mix similar sheens/colors so you don't end up with something funky. That mixed up leftover paint comes in handy if you're painting basement walls or some dingy shed or really any paint job where great paint is not needed to get the job done.

 

+1 Leave it in the original can. Wipe the top lip/groove out with a clean rag and seal it up with original top. It will be fine.

 

Well, I dont do this, but they make a produce called Bloxygen, that is a gas, you can spray in the can before putting the lid on. Some people have suggested holding your breath and exhaling into the can before capping it. Glass jas will probably work the best if its a very small amount of paint. Or, you can buy empty quart and gallon cans from a paint store. pour your paint in a new can carefully, and dont get any on the lid, and it should be good to go for years if stored correctly. Some people suggest storing the cans upside down as well...

 

Put the lid on tight, store the can upside down. If a thick film forms it will be on the bottom when you open the can.

The problem with putting the paint in another container ... you lose all the label information about brand, color, sheen etc.

 

The problem with putting the paint in another container ... you lose all the label information about brand, color, sheen etc.

I created an Excel table with info like colour name, code, base code, etc. Besides, my paint store keeps a record of everything they mix for their customers.

 

I'd vote for the smaller cans from a paint store. The less air in the can the better. The people we bought this place from left us heels of paint in plastic tubs - didn't last. The only can I've ever had rust through was a Zinsser's product but I can't remember which one.

 

Years ago, I got access to many small glass jars, that originally held, toddler food.

Used many to hold less than a pint of old paint in them.

I do not know if Baby food still comes in glass jars, but I would guess that one could use clean pickle, jam, syrup, and the list goes on, jars / bottles.

That one that you had rust, must have gotten a lot of water dripping on it, over the last few years.

ED

 

Do NOT put the paint in a plastic container, as I once did. 😁

I put about a pint of oil-based paint in a large yogurt container. Sealed it nice and tight with duct tap too and set it on a shelf in the garage.

After about 6 months I went to use the paint and the container had warped and shriveled up. It was OK, but I think if I had waited another few months, the container would have exploded or melted, and made one heck of a mess.

 

Ah! Glass jars! I've been using those for carpenter bee traps. But yeah, better than plastic soup containers!

 

Throw in some dry ice before you seal it up?

 

Smaller paint cans (available at big box stores) help. You can also put a layer of food wrap across the top before you seal up the can.

 

Bloxygen being argon (I think) and gases such as CO2 from exhaling into a can only work with finishes which cure through oxidation which would include paints containing drying oils. They won’t work with WB acrylics, lacquers, and most waterborne finishes except for maybe hybrid emulsion paints.

I just use a couple of layers of stretch wrap stretched tightly around the lids where meeting the can to inhibit evaporation with waterborne paints which works great.


Edit:
Figured I’d add one benefit which Bloxygen & CO2 could provide when used in WB paint cans is displacing oxygen which would inhibit odor causing aerobes from growing in the cans or on top of the paint including mold.

 

OK, but you don't have to generalize that to "don't put any paint in any plastic container". Sherwin Williams was actually selling their (acrylic) paint in plastic containers for awhile. Obviously some plastics can handle oil based products just fine. I mean, paint solvents come in plastic containers, after all.

 

I make something called "drift cards". I take a sample material (piece of file folder etc.), prime it, paint it with plenty of coats (so it's nice and opaque and not influenced by primer color)... let it dry for a year somewhere dark, then into a Ziploc bag and into the file. Next time I need a match, take it it to the paint store.

I don't attempt to save old latex paint because too often it has gone moldy/mildewey. Thank Los Angeles; the SCAQMD has forced paint makers to remove virtually all VOCs (chemical paint thinners) so there's nothing left in the can that's toxic (to mold).

They could make a separate family of paints just for L.A. but most just bring their national-market paints into L.A. compliance.

Ask anyone who's accidentally painted with moldy paint, it is a horrible nightmare. You try to paint over it to "seal-coat it", that doesn't work. You try 10 different things, eventually you must just strip the paint off and start over. Days of work.



Anyway with alkyds ("oil"), I just move them to smaller cans, being careful to label. With alkyds if the can isn't nearly full, the air trapped in the can will make the paint get a skin. I buy smaller cans in 24 quantity.

With 2-part paints (LPU and epoxy) I just leave them in the original cans: first for safety/MSDS labeling reasons (they are toxic and first responders need that label), and second because they don't have a problem skinning over. They react with each other, not air.

OK, but you don't have to generalize that to "don't put any paint in any plastic container".

You sure can't. The manufacturer has engineered it to work with a particular paint in a particular breed of plastic. As Joe Consumer I couldn't know what to buy. Heck if it wasn't for recycling marks, I wouldn't even know which breed of plastic a thing is, and that only works for 5 of them (#1 and #2 are effectively the same plastic for these purposes).

Sherwin Williams was actually selling their (acrylic) paint in plastic containers for awhile. Obviously some plastics can handle oil based products just fine. I mean, paint solvents come in plastic containers, after all.

I've never seen an alkyd paint in a plastic container. Never. I have seen "waterborne alkyds" which claim to be oil-based but water-borne; I'll grant you that is a thing, but I thoght you needed very special gear to assure agitation.

I created an Excel table with info like colour name, code, base code, etc. Besides, my paint store keeps a record of everything they mix for their customers.

That's useful for a few years. But if you try going back 15 years later, they won't be able to find "Mellow Peacock" or "K1411" in their book (typical whimsical color name). The sticker on your old paint can is readable, but 2 of those pigments were discontinued. (read: the new pigment liquid has less pigment potency than the obsoleted one, which had too much VOC, thanks L.A.)

If you call around enough, you'll find a shop that kept their old chip cards/books, and they'll just stick their chip on the Xrite machine and create a new formula using modern pigments.

All pigments from prior to the 1980s were lost because they relied on mineral pigments (lead chromate, fun stuff).

"Why do we bother" ...

 

And I use small plastic containers, Cottage cheese, sour cream, and similar, as temporary holders for small touch up jobs.

Then dispose of the container, and get another , next time.

ED

 

Instead of excel sheets, these days you can snap a pic of the label and send it right into a dropbox folder and store it in the cloud.