Enamel paints, small lots

[Don Y]

I keep an assortment of "Testor's" enamels on hand (think: models) for odd "marking" jobs -- times when I want to apply color to something to make it more readily visible (e.g., "legends" molded into items that inherently have no real CONTRAST to make them noticeable).

The tiny bottles are great because they don't take up much space, give me an assortment of colors, dry quickly, etc. And, the aroma is definitely nostalgic!

But, they eventually dry out -- it appears the seals aren't intended for multiple openings and closings.

Can I buy similar paints in containers that are more readily resealed? Or, modify the containers so that they seal better (they seem to just have a metalized cardboard "seal" tucked up into the cap)? Or, transfer them to different sorts of containers?

Or, just resolve myself to replacing the individual paint bottles despite how much (hardened!) paint remains within? (this means keeping spares on hand as you never know when you'll go to use a bottle only to discover that it has dried out)

[clare]

Put saran wrap over the bottle before putting on the lid or store the bottle upside-down or place a few drops od reducer on top of the paint before closing the lid. Do not shake, stir or invert. The reducer/thinner will keep the paint from being contacted by air/moisture in the bottle.

[Frank]

They are in bottles with metal caps and should not dry out when closed but solvents are very volatile. I see from them that they do recommend stuff for thinning:

Nail polish remover may be a cheap solvent to use as would be acetone.

[Don Y]

I think the problem lies in the metalized foil piece of cardboard that fits inside the cap that is intended to act as a "rubber washer" to seal the imperfections between the metal cap and glass bottle "rim". As it has very limited flexibility, it is probably not intended to see many "use cycles": open it, paint, close it. Repeat once or twice (but not dozens of times).

Perhaps I should try fitting a piece of rubber into the lid, instead.

I've got a bottle of their thinner (comes with each "set" of paints) that I use to clean brush after use, etc.

I've no idea of the age of the current set of paints. The red bottle sees far more use than any of the others. And, it is still "essentially full". As I said, I'm just using these for marking so I waste more paint *in* the brush than I ever actually apply. This leads to lots of open/close cycles but very little paint *usage*.

E.g., last night, I used it to highlight the embossed "paper goes here, not there!" icons on two of my scanners (because I can't see the raised, same-color plastic molded into the top of the scanner's plastic case UNDER the lid when trying to load a sheet of paper). A single "drop" of paint would have been much MORE than I needed to highlight the icons on BOTH scanners.

[Unlike watercolors, I don't think pouring thinner into *dried* paint is going to rejuvenate it]

[dpb]

...

...

I keep something like these instead...

Not as many colors available, but no brushes to clean, etc. They will dry out eventually as well, too. No idea what relative cost might be; haven't price the model paints since "like forever" when was a kid...

OTOH, there are some half-pint cans of paint been around the house here that some must date to the 50s that when open are still apparently as good as new...then again, they haven't been opened generally for 40 of those years so no idea if would've sealed/remained ok if used more than the one time when were initially bought.

Of course, if you were to instill a "preventative maintenace" program an replenish the solvent periodically (and you're right simple acetone will work fine; it's probably cheaper by the pint or quart at the Ace than buying nail polish remover, though, altho again there's a volume issue of it'll also evaporate in the can over time) you could probably extend the usable bottle time almost indefinitely at the cost of another chore.

[Don Y]

Unless your Saran Wrap is heavier duty than ours, it just tears. Do you recall how *small* the bottles of Testor's are?

That *might* work. But, i suspect paint getting on the underside of the metalized cardboard "washer" is what has caused the problem in the first place -- i.e., interfering with how well the cap/washer "seats".

I'd think a better solution would just be some sort of container that seals better!

SWMBO gets her paints in "toothpaste tubes" (sort of). I'll check to see if I can purchase enamels in a similar form (though they may be too fluid for that sort of dispensing).

[Don Y]

I use those to label (for example) the "USB icon" on the A-side of USB cables. With a steady hand, you can almost trace the shape.

But, the paints are more universally applicable.

E.g., I have painted the "mounting brackets" of my differential SCSI HBA PCI cards red so I can easily recognize "this one is differential while this other one -- that looks identical to it -- is single-ended".

Yeah, I think the opening and closing is what is eating my lunch. I.e., the other colors in the kit are good as new. It's the ones that see the most "access" that seem to dry out quickest.

We keep MEK, acetone, spirits, xylene, etc. on hand as we use them often enough. So, adding some to the paint each time it is used is possible.

*But*, how do you decide "how much"? Weigh the bottle each time you seal it and then add solvent to it BEFORE each use to restore that same weight?

[clare]

Yes I do, and I've done it in the past - with both the testors bottles and the Humbrol cans.

Buy Humbrol. Snap on can lids.

[clare]

Not for thinning enamel!!!! Mineral spirits is best - turps will also work.ANY enamel paint thinner.

[clare]

Putting a film (of thinners) over the un-thickened paint keeps it from thickening though.

[clare]

Spirits or possibly xylene are much better than MEK or acetone for these enamels - or use ronson lighter fluid. (naptha)

[Frank]

Depends on the base resin. If acrylic then nail polish remover or acetone would be better than mineral spirits.

[dpb]

On 4/4/2016 3:27 PM, dpb wrote: ... We keep MEK, acetone, spirits, xylene, etc. on hand as we use them often enough. So, adding some to the paint each time it is used is possible.

*But*, how do you decide "how much"? ...

It isn't when you use it that's as critical as the time in between usage that may be quite some time; altho you'd certainly at least extend life some.

It's not critical, thin 'til it's just a tad thinner than the consistency you'd like to use...but again, it it's two years before you use that particular one again and you've not checked and "topped it off" it may be too late.

[Don Y]

Testor's thinner smells neither like acetone nor spirits. It claims to contain: n-Propoxy Propanol and Xylol

As I've, to date, only used it to clean the surplus paint off the dinky little brush at the end of each use, I haven't even exhausted the 1/4 oz bottle that came with the paint set -- though I have a gigantic 1.75 oz (!!) bottle that I will use to refill that little bottle when it's exhausted.

[And, I note the large bottle has a large conformal "plug" that fills the opening instead of just relying on the "metal cap" for a seal!]

[Don Y]

Exactly. Hence I'd rather have a *seal* that is more reliable and not NEED to worry about it drying out. It can easily be a year between uses -- or, every day for a week! It tends to be driven by new kit or new uses for old kit.

E.g., I've had the scanners for several years. But, only recently moved them to a different location that is not as well lit -- nor readily accessible (all I need to be able to do is slip a piece of paper onto the glass and KNOW how it should be oriented so location need not be "prime"!)

[hrhofmann]

My solvent of choice is Naptha. It seems to work very well.

[clare]

Testors enamel isn't acrylic unless they've changed in the last couple of years. I've had the sruff go all stringy and useless using the wrong thinner. Acetone and MEK work for cleaning, but I wouldn't use it for thinning - particularly on styrene. Even laquer on styrene makes a terrible job. (it eats into the surface and wrinkles)

[Terry Coombs]

Throw a couple of turns of black electrical tape around the lid after you righten it .