Borax in methanol=better contrast agent

Community Laser Talk
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So I poked this idea around for awhile. Water is slow to penetrate wood, slow to dry, and can swell/lift the grain.

I went out and researched what other solvents could be used. Ethanol, isopropyl, methanol, acetone, vs either baking soda or borax.

Of those, only one combo has good solubility: borax in methanol. I didn’t need to experiment, precise solubilities are well documented. Mixing water with these alcohols doesn’t seem to have a sweet spot- adding water would require such a high % that it would bring back the problems I wanted to get around before adding much to its capacity to hold borax or baking soda.

For this, I found Wal-Mart has 10oz isopropyl spray bottles. Perfect. I emptied the isopropyl into another container (who doesn’t need isopropyl?). Then, in a second container, mix methanol with “too much” borax so it saturates and sits on the bottom. It generally doesn’t need much time to fully dissolve as much as it can at room temp, and we don’t want to heat it because it will be supersaturated at room temp and clog the sprayer.

If you have any sediment in the spray bottle, it’s likely the sprayer straw will pick it up off the bottom first and clog. That’s why we’re mixing in a separate container- just decant the saturated methanol only into the spray bottle. Add a small amount of methanol to give it some margin from saturation so evaporation or temp shift doesn’t make it fall out of solution again.

You can save the second container and just add more methanol and borax to keep from wasting the remainder, keep it for refilling the 10oz sprayer

I gotta say, looks notably better to me. The sprayer makes a finer mist than I get with water, it coats the plywood evenly, soaks in deep pretty aggressively, and is totally dry in a few minutes.

Methanol does have some toxicity to it, more so than isopropyl. It’s got some inhalation hazard, and is readily absorbed through the skin. It would be hard to see getting a troublesome exposure from “normal” use, but do your own research there. Spray it on wood but keep off the skin. It shouldn’t be dripping with it anyways.

The results seem pretty great! It darkens the way you expect borax to do, but it’s a smoother, deeper blackening. No grain swelling, dries super fast. Adds some toxicity concern but shouldn’t be significant in normal use.

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A bit off-topic:
Have you noticed.. that over time the wood gets ‘yellow’ after applying Borax solution?

That is the reason I don’t use borax anymore.

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YIKES!!!

Methanol is HIGHLY toxic!

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@Dannym, thank you for the research and writeup. Although you minimized the safety warning, it was included and should tive everyone warning.

@sensor mentioned his yellowed over time, maybe coating it with water-based Urethane spray (Varithane) will minimize this color shift. Then again, the yellowing might give an old timer look.

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Methanol is being used as an aerosol.

As little as 3.16grams (0.11oz) can cause optic damage with inhalation causing nerve damage.

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Well he’s spraying it not drinking it.

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it is a systemic toxicity, but it has a significant threshold. methanol is a byproduct of ethanol fermentation and present in all wines. 150-250mg/L in red wine. up to 20mg in a std glass of orange juice.

methanol metabolizes into formaldehyde then formic acid, and the formic acid is the actual toxic part.

methanol is notably problematic in that it is highly absorbable through the skin. while you might use a bit of isopropyl to clean ink off your hands, you should never do that with methanol. most people think about it in terms of whether it dries out or irritates the skin, it will probably dry out skin but the problem is absorption. but it would require quite a lot of skin exposure to exceed a toxicity threshold, more than would make any sense from handling wood while spritzing a bit on it.

I’m trying to think through how to reasonably frame the risk. “don’t drink it or use it to wash your hands” covers most of it. obviously don’t let it spray in your eyes, but it’s not that different than the 91% iso that the spray bottle first had in it.

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That’s a lot to inhale from a fine spray.

Per the Methanol Toxicity writeup:

Toxicity may also rarely occur through extensive skin exposure or breathing in fumes.

Spray it outdoors, stand upwind, and it’ll be all good.

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it is a systemic toxicity, but it has a significant threshold. methanol is a byproduct of ethanol fermentation and present in all wines. 150-250mg/L in red wine. up to 20mg in a std glass of orange juice.

methanol metabolizes into formaldehyde, neither are really harmful, but then metabolizes into formic acid, and the formic acid is the actual toxic part.

methanol is notably problematic in that it is highly absorbable through the skin. while you might use a bit of isopropyl to clean ink off your hands, you should never do that with methanol. most people think about it in terms of whether it dries out or irritates the skin, it will probably dry out skin but the problem is absorption. but it would require quite a lot of skin exposure to exceed a toxicity threshold, more than would make any sense from handling wood while spritzing a bit on it.

I’m trying to think through how to reasonably frame the risk. “don’t drink it or use it to wash your hands” covers most of it. obviously don’t let it spray in your eyes, but it’s not that different than the 91% iso that the spray bottle first had in it.

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I think this discussion has run it’s course.

Methanol has specific considerations that must be taken for safety. Here’s the MSDS sheet.

https://www.fishersci.com/store/msds?partNumber=AC423950040&productDescription=METHYL+ALCOHOL%2C+ACS%2C+99.8%25+4L&vendorId=VN00033901&countryCode=US&language=en

We are not recommending methanol as there are many other delivery methods for borax that would be less dangerous - but if it works for you, thanks for letting us know. Follow all MSDS recommendations, as always!

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The alcohol drug conflict of the 1920’s legislatively added methanol (wood) to ethanol (drinking alcohol) to poison it. Killed about 10,000 people they believe.

As @Colin advised, I’d also suggest not using methanol.

:grinning_cat:

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