An Easy Borate Indicator

[Don P]

I was curious about my penetration depth from rolling borate on, stickering and turning the fans on. So I took a slice from a waney year old red oak 1x6 and dipped it in a homebrew boron indicator, thus polluting my reagent :D... waalaa;


 
I was in the pharmacy killing time while they counted pills, spotted this when it occurred to me, you can get turmeric in the spice aisle as well, its all the same ground up root of a relative of ginger. Main ingredient in curry.

Curcumin is an indicator for boron. When boron and curcumin mix it creates rosocyanine a bright orange compound as compared to the yellow of the curcumin solution. Give it a few minutes.

Curcumin does not dissolve in water so you need to make a solution in one of several spirits. I had acetone handy so grabbed it, high proof alcohol should work as well. I mixed and shook it up, strained through that Kleenex in the background into the spice jar you see with a little solution left in it (slightly oranger than it was before dipping in it) then dipped my slice in that end for end, yup I got yaller fingers. Best not to do it near anything the boss will hang you for staining.

[Nebraska]

Looks to me like it would withstand a moderate amount of planning,  1/8"  of penetration  or better. Was this plain solubor and water or glycol borate? Got to love better living with chemistry. 8) Neat idea Don.

[Don P]

It was just solubor and water with a few drops of dish soap. I began drying it right away so wasn't really trying for deep penetration, just a barrier which it looks like it did. This doesn't really tell anything about concentration just presence of boron. We did the same to the framing and sheathing of the little house which I later planed and edged. I might take a spray bottle of indicator and see if it shows anything left in it but had planned on doing a spray of glycol/borate on the whole thing before we button it up just to be sure.

My mix there was 4 of the 500mg capsules emptied into acetone that was about up to the narrowing on that bottle, that was more than enough curcumin in the mix I think. I suspect something like high proof vodka might be a better solvent, just guessing a little slower flash off might be better. And then I can try turning a banana orange :D

[farmfromkansas]

Glad you posted this, think I will copy you and just use a bucket and roller to apply my solubor.  Along with a few drops of dish soap.