Testor's bottle paint going bad; air leaks or why?

[Wickersham Humble]

I have quite a large collection of Testor's Pla and other small-bottle paints.  The latest cost $2.69 per at Hobby Lobby, but some still have the 15-cent label on the lid!  Now, I'm not surprised at some of them 'going bad' considering the age of a few, but a number of bottles only one/two years old have gotten hard, or turned to clumpy glue recently.  I wonder: Iike the marbles in the bottom of our aerosol cans (the famous 'rattle') I have been adding 3-4 metal B.B.'s to each of my bottles to help keep them well agitated until needed.  However, does anyone think that good old Daisy copper-plated B.B.'s would have an effect on hobby enamel paints?  I'm beginning to wonder... 

Some I can rehabilitate by adding lacquer thinner, some not.  Ideas?  I'm not switching to water-based.

Thx!  Wick

PS/  Now I appreciate why Testors and a few other brands use square-cornered bottles: I can put the old ones in a vice, and use pliers to dislodge the painted-shut lids!  Tamiya and others with round containers, take note!  (Only had one break in my experience, and it was dried out anyway!)

[1972coronet]

1 hour ago, Wickersham Humble said:

Tamiya and others with round containers, take note!  (Only had one break in my experience, and it was dried out anyway!)

To break those caps loose, I run the bottle - cap-side-only - under hot running water. That usually does the trick. If they're extra testy , I'll smack the lid with the blunt side of pliers.  

Edited December 22, 2024 by 1972coronet
*TYPO*

[gman]

I have experienced that with Testors bottle paints- from the 70's to present. Some colours are worse for that than others.

Sometimes they separate and clump on the bottom (and no amount of mixing gets it back), sometimes the solvent seems like it gassed off leaving a curdled clump in the bottom of the jar- even when the jar has never been opened. The flat colours always seem to do this over time. Lacquer thinner may get them usable if you won't be overcoating other enamels with it. A safer bet would be Testors airbrush thinner which I have used multiple times. These days I leave the Testors enamels alone for the most part as there are better paints available- whether you'll be brush painting or spraying it through an airbrush.

As for opened bottles that have sealed themselves shut, running a flame around the edge of the metal cap sometimes helps but if it is really stubborn, turn it upside down and put a few drops of laquer thinner inside the edge of the cap and let it sit that way for a while.

[Wickersham Humble]

Reasonable strategies; sorry you're having problems with them too.  I wasn't sure many avid modelers still use them with all the well-publicized alternatives.  I just bought a little jug of lacquer (Japanese WWII a/c) from MCW, and a Pontiac OHC six which fascinated me, but I have no kit for; maybe a street rod?

Yeah, I've had some issues with Tamaiya colors too, but usually not until the jar gets past the half-used level; I like 'jet exhaust' for carbs, m-cyls, stuff like that.  Also, I need 'stop light red' fairly often, and the 'smoke' hue.  I paint my kits with mostly PPG auto colors, bec I used to work for them (retirement job, got laid off at age 71) and I had/have access to a lot of mis-match colors, even in gallon lots!!  Never had a problem on styrene; knock on plastic!  I do toss the old Testor's jars and lids into my gallon soaker of lac thinner, and rebottle some colors in them; not always successfully, I'll admit.  The little craft store glass jugs seem to leak air; noticed a number of mine had gone away already, darn.  But no info on B.B.'s causing problems, so that's good.  Wick

[slusher]

I have opened stubborn jarsI use a small pair of Channelocks. That will fit in your poocket. I keep extra bottles paint on Hand but if it’s not good I will toss it out not worth reviving a dead jar of Testors paint  don’t need another problem! 

Edited December 22, 2024 by slusher
Typo

[bobss396]

I gave up on the Testors enamel decades ago.

I made the leap to acrylics like Tamiya and Vallejo and have never looked back.

[Miatatom]

I always clean the bottle and lid well and place a small piece of Press and Seal on the top before replacing the lid.

[LennyB]

I like to store the bottles upside down, it helps keep them from drying out as air doesn’t seep in the lid. As for reconstituting old paint I’ve always had good luck adding a bit of testers thinner, not brush cleaner mind you, different animal

[Mike 1017]

Micro-Mark sell this.

 

 

 

 

Edited December 22, 2024 by Mike 1017
wrong word

[Mark]

The OLD bottles of enamel can be revived with thinning (with decent quality enamel thinner) and thorough mixing.  Shaking alone won't get it done.  The five-cent ones ought to be usable, as they've probably still got some lead (among other nasties) in there.  The bigger the skull and crossbones on the label, the better it will work, and for longer.

If they're drying out, air must have gotten in.

Avoid using channel lock pliers or vice grips on the caps unless absolutely necessary.  Same goes for putting the square bottles in a vise; they do break.  Save caps from used bottles, and use them when needed to replace those subjected to vice grips and other hackery.

The "turn the bottle over, and put a couple of drops of lacquer thinner on around the bottom of the cap" works the vast majority of the time.  The vice grips come out only after that fails.

Don't put the cap back on until the opening on the bottle is wiped clean.  That prevents future troubles 99% of the time.

Edited December 22, 2024 by Mark
D--- spell check

[peteski]

Once enamel type of paint turns into gel or rubbery clump it cannot be revived. You can add some type of thinner, but the paint will not turn into usable liquid again. Even if you mix it back into liquid state, the liquid will consist of very small chunks of the gelled enamel paint. Not usable.  That is because when enamel dries (actually hardens) it goes through a irreversible chemical reaction.  If enamels are still in viscous liquid state (not gelled) they adding thinner will still make them usable.

Thickened or dried lacquer paints on the other hand can be readily be made usable again by adding the appropriate thinner to them. That is because lacquers dry solely by solvent evaporation.

[bill-e-boy]

I think the problem is that you opened the jars and let the air in when you put the BB's in. I to have a whole bunch of Testors square jars and the majority are still OK. If the lid is hard to get off chances are the lid will not reseal properly so I never open a jar until it is needed. 

I use a nut cracker to open tight jar lids

[Wickersham Humble]

Yeah, sad to say, but I guess when the clock starts ticking on paint, it has a finite life left.  I was mostly just speculating on the addition of the B.B.'s since so many of those have tanked.  Outsmarted my ole' self?!

I've rebottled a lot of colors and paint types, having done the mixing job (along with delivery route) at our local PPG outlet, Martin Auto Color: my wife saves those tallish square spice jars for me, and with a big sticky label to spell out all the details of the paint (type, source, name and application -- if known -- and whether catalyzer required, etc.) paint-stain-proofed by a wrap of clear shipping tape, and mostly it's been okay.  The spice jars usually have a poly-ethylene perforated shaker lid beneath the cap, so I trim that out leaving the perimeter to serve as a cap gasket.  OC, they go through the dish-washer first.  Until the gasket seal tactic, those often leaked or dried up, I must admit.  I have lots and lots of 1/1 car finishes, naturally, and almost overwhelmingly they work okay on styrene models if they're primered properly first; eg. so far no failures in forty years!  Doing 1/1 restos, I just accumulate them.  Anyone want a pour off from a gallon of PPG Hemi orange, slightly metallic?  Before y'all jump on this as bogus (as I was inclined to do) the store manager, a life-long MoPar guy, said that it was a rare exterior color one year... I dunno.  I even have most of a gallon of USAF-issue o.d. (olive drab, to you civilians) lacquer that I got from CA state surplus.  If you're ever in town...?

I even have a few of the very old Aurora rectangular paint jars left; the paint long defunct.  Surprisingly, when I used it c. 1962, it brushed-on gratifyingly well, dried slick and fast!  Actually, I did my MA thesis and show on using air-sprayed paint for sculpture, etc.  Mine were mostly - not surprisingly - race and custom-car, aircraft, and truck shapes and colors.  I'm too 'senior' to convert to water-based stuff; it's a whole different world.

Thanks again for the enthusiastic responses; count on MCM Forums for a helping hand!   Wick in N CA

[peteski]

Here are some older topics related to vintage hobby paints.  Fun stuff!

 

[deuces wild]

The testors bottles I have are around 27 years old....

[bobss396]

I had some PLA paints with 5 cents marked on the lids. I recall Testors going for 10 cents back when brush painted everything.

[Wickersham Humble]

No man is an island -- he's a peninsula!  Jefferson Airplane

I know that there were other brands too, but don't have any left -- probably just as well!  Five cents was about in my budget, in the 'fifties!  Thx!  Wick

PS/ Due to a hacker, I had to change my email address, so my forum status is back to rookie Jr, Woodchuck!

[peteski]

2 hours ago, Wickersham Humble said:

PS/ Due to a hacker, I had to change my email address, so my forum status is back to rookie Jr, Woodchuck!

You could have contacted the forums moderators to help you to go back to your original account (and probably even merge your new posts to the original account.  They are a helpful bunch. To me that makes more sense than starting fresh Mr. Humble.

[slusher]

Testors don’t want the paint to last. I have been using Tamiya, Mr color and craft paint more and building them slowly..

[peteski]

1 hour ago, slusher said:

Testors don’t want the paint to last. I have been using Tamiya, Mr color and craft paint more and building them slowly..

Do you really think that hobby paint manufacturer purposfully do something to have paint go "bad" quickly?!  I doubt that very much.  Plus many of us have 50 year old bottles of Testors PLA enamel which are still usable.  To me that is lasting.

Any paint will go "bad" if its container is not sealed.  I'm anal and make sure the lip of the bottle and the gasket in the lid are perfectly clean every time before I reseal the bottle, and I also shake the bottle after sealing (to have the paint fill and harden in any microscopic voids between the lip and gasket, but most modelers just screw the lid back on, so the paint crusts up over time, preventing a good seal from forming.  Then their paint dries up rather fast. Not manufacturer's fault.

Edited December 24, 2024 by peteski

[rattle can man]

Making sure the lid and bottle are clean is a big must. Use hot water and minimal force if they are stuck. Brute force can bend the metal lids out of shape, and once bent, they will not seal properly. An open flame would be questionable, since they are flammable. Plus excessive heat combined with a sealed container could lead to failure, from pressure, of the lid (flying across the room, along with some paint) or bottle (cracked or shattered glass) with paint getting everywhere, at a minimum.

[Wickersham Humble]

"For what it's worth" Something happenin' here... what it is ain't exactly clear...  

So far, in my latest usefullness-check of my Testor's bottles, every single one that went 'curds and whey' on me had my infamous B.B. treatment!  And in all cases, the copper covering on the B.B. had been neatly stripped off... so chemists out there...??  No more B.B. agitators for me!  Ole' Wick

[gman]

5 hours ago, rattle can man said:

Making sure the lid and bottle are clean is a big must. Use hot water and minimal force if they are stuck. Brute force can bend the metal lids out of shape, and once bent, they will not seal properly. An open flame would be questionable, since they are flammable. Plus excessive heat combined with a sealed container could lead to failure, from pressure, of the lid (flying across the room, along with some paint) or bottle (cracked or shattered glass) with paint getting everywhere, at a minimum.

The solvents in Testors enamels are not that "hot" so while flammable if you intentionally try to light some on fire, licking the flame from a lighter around a stuck cap does not result in shattering jars or pressurizing the jar to the point bad things happen. The metal cap heats and expands at a different rate than the glass jar, and all that happens is that it slightly breaks the seal so the cap can be unscrewed.