Preserving paints?

I've got a handful of "classic" Testors enamels which I would estimate to be around 30 years old. (Had them from before I switched over to Tamiya acrylics when they first hit the market in the early 80's) These are still quite usable, some of them having never been opened. (Well, I assume they are still usable, as they will mix when shaken)

Tamiya's enamels (yes - enamels, which are available in some countries) are another story, These will dry out in the jar within a few years, even if never opened. I've seen it happen in a jar that I bought to try when they first came out and seen dry/almost dry jars on the rack in a LHS.

I have some paints that are 20+ years old and are still good, while I have purchased some about 1-2 years ago and those have gone rubbery on me. Just two nights ago I went to open a small Testors flat red little botttle I bought at Hobby Lobby about a year ago and it felt like silly putty. Yet another bottle of Testors bought over 20 years ago with a .19 price tag on the cap is still good! I wonder if paint companies are adding a shelf life to their products to make sure you come back for more.

Jimbot58, I'm with ya. All those things you listed follow right along with the boat I'm in. And I really hate acrylics. Those I've used have been to delicate to handle and I fear masking them because I've had way to many problems with the paint lifting. I'd rather build models than spend years and hundreds of dollars trying to learn a new system.

jimbot58,

I have been experimenting with the caps off 20 oz Diet Coke bottles (of which I drink too much of). The seals inside the plastic caps fit exactly into the metal lids of the paints. Whether they will hold up to the solvents in the paint only time will tell.

Excellent idea! I will start collecting them for now on. You should submit this into FSM's 'reader's tips'

Holding up to the solvents is not a issue if the paint is kept away from the lid & threads. Besides the pop bottle gaskets can withstand regular Coke. I use a stainless steel pin to dip the paint out onto a clean piece of glass to work with. Thinner is in a eye dropper blue puttied to a jar for immediate use. It is a bit messy & wasteful but works for me. I will take a pic. & post when I am set up brush painting.

hkshooter

I'm also a user of MM enamels but I get so aggravated at the rubber plugs I find way to often. I've had unopened bottles turn to rubber and others I've only used once do the same. I'm dilligent on keeping the lids, bottle necks, and all threads clean to no avail.
I've been so aggravated that I'm considering switching to something else.

I am the same as you but the problem is multi-fold:

1. I don't play well with acrylics and they don't play well with me.

2. I have used MM paints so long, I wouldn't know how to use anything else.

3. I have so much invested in MM paints (and I should own Testor stock after all these years!) it would be difficult to change!

4. The color selection is pretty good, I don't know about other lines of paint!

I'm also a user of MM enamels but I get so aggravated at the rubber plugs I find way to often. I've had unopened bottles turn to rubber and others I've only used once do the same. I'm dilligent on keeping the lids, bottle necks, and all threads clean to no avail.
I've been so aggravated that I'm considering switching to something else.

Its quite true of Testors MM enamel......two simple things to help

1. Wipe the glass lid of the bottle clean of all paint

2. Use a Q-tip to wipe the paint out  inside the metal screw cap so the seal is intact when you close it.

I do this every single time before I close a bottle and it seems to help. No name Q-tips are very cheap.

Gentleman,

there's an easy fix that helps preventing drying paint in the container and costs nothing. That powerful concept is storing the jars or also tins upside down. By doing so the paint itself seals any excess air out and the drying surface is drastically minimized. It works all right for my humbrols, and also for paints in jars.

There's also the problem of excessive tightening of the lids - doing so might distort the lids a little and instead of improving the fit of the lid it could make it worse. So I'd not recommend gronking the lids star-tight.

There's also the point of brush cleaning agent residue on the paintbrush contaminating the paint in the jar - happened to me too before. It's important to dry the brush well before dipping it in the paint container.

Hope it helps, have a nice day

Pawel

I wish they all used bottles like Tamiya or a cap similar to Alclad's. Some people store MM bottles inverted so the paint will seal the cap but if one has a pretty good leak it will at least leak into the threads. I just keep them clean and right side up. I lose a bottle occasionally but live with it. One shop in the area is charging $3.99 a bottle for MM but the other two charge $3.29.

Tony

I see from the responses here that I am not the only to have MM paints go bad, so it is not just me and my methods. I also have found that adding thinner of any type seems to make the paint go that much faster.

I have been experimenting with the caps off 20 oz Diet Coke bottles (of which I drink too much of). The seals inside the plastic caps fit exactly into the metal lids of the paints. Whether they will hold up to the solvents in the paint only time will tell.

The actual price I pay here is $3.49 which is well on it's way to $4! Squadron sells it for $3.33, Internet Hobbies for $3.29 and Sprue bros seems to be having a sale  at $2.99 right now. I am not really paying that much more than internet prices and I don't pay shipping charges.

I use acrylics so this is not directly applicable, but I've bought a gallon jug of distilled water and a small syringe. When I notice the paint starting to get thick I'll add one or two cc's of water. So far this has been working well. Being enamel you would need to add thinner and I remember back when I used enamels the paints were very sensitive to what thinner you added to the bottle, some actually thinning the paint as desired and some reacting overtime to create a rubbery substance in the bottle.

I've seen canned nitrogen (like the canned air for cleaning computers) sold to extend the life of resin in the jug. Perhaps that would be a possibility to extend the life of the paint, just a little squirt to displace the air before putting the lid on.

Clean the top of the bottle especially the threads and rim. Make sure the threads on the cap are clean as well. Lay a piece of aluminum foil over the opening large enough to let the cap secure it in place when the cap is screwed on. You can use wax paper as well, but if you elect to use plastic wrap, test it to see there are no adverse reactions such as melting the plastic.

Replace worn lids with new ones.

Adding a thinner, especially one that is not the mfrs can cause the paint to react over time. Dissimilar solvents tend to react in less than acceptable ways. Once air has been introduced, the paint will also begin to slowly  separate and degrade.

jimbot58

nearly 4 dollars for a 1\2 oz. bottle it can be expensive!

Nearly $4? 

I'd highly recommend buying online, at least for the paints you know and don't need to see before buying. Bottles are typically a dollar cheaper than you'll find at Hobby Lobby or wherenot, and if you tack them onto an order or stock up on enough paint at once you'll easily come out ahead, even with shipping.

I have noticed Testors enamel gums up faster than any other model paint I use, but only after opening. I have wondered if just the increased air volume as paint is used is responsible.

I have begun to buy paint new for each project I start.  With the cost of models going up so much lately, I find the cost of new paint is a minor expense.

In spite of the "going bad rapidly,"  I still like Testors enamel and it is my primary paint.

Agreed,

One thing I do before closing the bottle is to put a few drops of thinner in the cap. It moistens the paper gasket with the logic being it can evaporate from there fist before drying out the paint.

What is really needed is upgraded gaskets, the paper ones work and they do keep the costs down but maybe the AM could run with this idea and sell better ones.