Preventing solvent evaporation in bottles of Accu-Paint and Tru-Color paints

[peteski]

George's post in another thread reminded  me to post my method of keeping those paints stable.

I'll also mention that the plastic bottles that Tru Color comes in seem to allow slow evaporation.  Even hitherto unopened older bottles have appeared half empty and too thick to spray well.  Easily remedied by adding Tru Color thinner (again, not just Acetone).   In my experience, when spraying Tru Color paint, thinning to the right consistency is more critical than the air pressure adjustment.

Accu-Paint (discontinued), and the currently available Tru-Color paints are very similar, so my method of keeping my 20+ years old Accu-Paints fresh also applies to Tru-Color paints.

George's observation is right on the money.  Both brands of paint are packaged in the same type of plastic bottle with the same type of plastic seal in the cap.  And the solvent does evaporate from them over time.  My solution is to transfer those paints from plastic bottles to 1 oz. (Floquil-style) glass bottles.  Solvent will not evaporate through glass. But I take it one step further:  I don't trust the plastic-coated cardboard seals in the glass bottle's caps. I add my own aluminum seals over the cardboard one.  Again, solvents will not evaporate through metal.  I got this idea from a quart-size can of Acetone.  Its cap came with a metal-lined seal, and there is no evaporation.



I make those metal seals from disposable aluminum roasting pans or cookie sheets.  I buy them in a dollar store, but they are not expensive even in supermarkets.  I look for ones which have large areas of flat surface.  They are made from aluminum that is thicker than aluminum foil, but still quite thin.  I cut up the pan and only keep the flat pieces.  Then using one of the cardboard seals extracted from the bottle cap as a template, I trace a circle on the aluminum foil. Then using curved scissors I cut the seals out.

After each use, before I replace the cap, I clean the rim of the bottle, and also the seal inside the cap. After screwing the cap on I shake the bottle to get the paint into the seal area.  If there is a microscopic gap, the paint will seal it.

I also take yet another step to make sure to keep the paint's original  viscosity.  After I reseal the bottle, I let the paint settle in the bottle, then I mark the paint level and date (month/year) using a fine permanent marker.  This is what it looks like:



If some slight evaporation occurred, I simply open the bottle and add thinner back to the marked line.  As shown here, there was very little evaporation, even in the bottle that was last sealed 8 years ago.

While this  all might seem like a lot of work, I actually enjoy doing all of it to keep my paints fresh.

I used to get my empty 1 oz. (Floquil style) glass bottles from Micro-Mark but it seems that they no longer carry them.  Walthers might still carry them. I have a a good stash, and lots of colors already in my collection, so I will not need to buy more for quite some time.

[daniel_leavitt2000]

Accu-Paint... that was part of SMP industries, right? I think they also did decals too, such as the Concord Car Shops line.

Since I use water based paints almost exclusivity, I like to use Badger jars. They match both my airbrushes and Modelflex paint jars. To keep them from drying out, I add Badger jar gaskets like these:

https://www.sunwardhobbies.ca/badger-air-brush-set-of-3-gaskets-for-50-208-and-50-308-jar-adapter-50-0241/

[peteski]

Accu-Paint... that was part of SMP industries, right? I think they also did decals too, such as the Concord Car Shops line.

Yes, that is correct.  The paint and decals were produced locally by George Bishop in Bolton, MA.  Those SMP decals were excellent quality, and the instructions included detailed drawings. Too bad they were only done in H0. Still, I bought several sets for the drawings and I was able to use some of the smaller B&M logos on some of my early N scale models.  I'm not sure if Concord Car Shops decals were printed by SMP, but those were also very good, and N scale.

George passed away several years ago, and SMP was no more.  I had a decent stash of Accu-Paints, but I was still ecstatic when I discovered Tru-Color paints.

[up1950s]

Somebody here suggested to me use a new piece of wax paper aprox 2.5 inch square over the cleaned rim of the glass jar and just screw the cap over that wrinkles and all . Give a shake when tight to seal the deal . Do that each and every time you open it . I keep a bunch of pre cut wax paper at the ready in a tube , hanging with arms reach . This idea was given me as a cure to opening problems because the paint glued the lids to the jars . As to evaporation I can't say , it hasn't been so bad if any to attract my attention .

PS 90 % alcohol comes in a plastic bottle .

[MK]

I don't know if these will work since they are 2 oz.  But they are relatively inexpensive as they come in a box of 6.

https://www.towerhobbies.com/product/jar-and-cover2oz-one-box-of-6-jars/BAD500053B.html

[DKS]

I replace the metal bottle lids having only somewhat useful metalized paper seals with Polyseal caps. Pretty much bulletproof, and they come in sizes that exactly fit Floquil (and other) bottles.

[Hedron]

Obvious, but I have had occasion to look there for bulk packs of bottles before, and Bezosville (Amazon) has all manner of small glass bottles and jars. Pro-tip: Put "JAR" in the search to get options with wider mouths.

[thomasjmdavis]

I replace the metal bottle lids having only somewhat useful metalized paper seals with Polyseal caps. Pretty much bulletproof, and they come in sizes that exactly fit Floquil (and other) bottles.

Based upon my previous experiences cutting and handling sheet metal of any sort, I think my fingers will vote for the DKS solution.

[wazzou]

Where are these found?

[DKS]

Where are these found?

Amazon has 'em.

Example: https://www.amazon.com/28mm-Poly-Seal-Screw-Caps/dp/B0064OFNGW

[peteski]

Thanks for the Poly-seal caps info DKS. Those should also work well.

I looked on Amazon for 1/2 and 1 oz. glass bottles, and I only found the Boston-type bottles. They are tall and have small necks. I prefer the Floquil-type bottles.

[haasmarc]

Tamiya sells nice glass paint bottles with tamiya's normal lids.  I got some this weekend and so far I like them.

https://www.1001modelkits.com/thinners-for-models/33256-tamiya-ta81044-paint-mixing-jar-0000045073977.html?gclid=Cj0KCQjwk8b7BRCaARIsAARRTL6FTMV0QlGLTQ0Bn_ySWb7KnRLG68OCM-HpzGsQqqEKJHUz6aieHA8aAm3VEALw_wcB

[peteski]

Tamiya sells nice glass paint bottles with tamiya's normal lids.  I got some this weekend and so far I like them.

https://www.1001modelkits.com/thinners-for-models/33256-tamiya-ta81044-paint-mixing-jar-0000045073977.html?gclid=Cj0KCQjwk8b7BRCaARIsAARRTL6FTMV0QlGLTQ0Bn_ySWb7KnRLG68OCM-HpzGsQqqEKJHUz6aieHA8aAm3VEALw_wcB

I have bunch of Tamiya acrylic paints in those jars.  The jars are nice but I hate the seal design.  It is very difficult to clean all the paint from the deep gap between the lid and the seal.  I really like to clean the lip and seal before rec-closing the jar, and those just don't make it easy.

[DKS]

I looked on Amazon for 1/2 and 1 oz. glass bottles, and I only found the Boston-type bottles. They are tall and have small necks. I prefer the Floquil-type bottles.

You're looking for Wheaton bottles. I got a bunch of these so I could mix my own paint colors.

https://www.amazon.com/Wheaton-Valumetric-Graduated-Capacity-Poly-Seal/dp/B003G2ZYQY

[peteski]

Again, thanks for the hint DKS.