dna drying

[midge29]

after some advice on dna drying please ,been reading on this dna drying using denatured alcohol , does anyone use this method of drying, what do you use as i read you need a license to buy denatured alcohol, does methylated spirit ,the purple stuff do the same job thanks nigel

 

[JakeS]

i read you need a license to buy denatured alcohol, does methylated spirit ,the purple stuff do the same job

Um... methylated spirits is denatured alcohol. All 'denatured' means in this context is that it's had some additive put in it, generally to make it unappealing to drink. To add to the confusion, methylated spirits is called as such 'cause it's got methanol in alongside the ethanol... but both are alcohols! (The pink stuff is something else, just a dye I think... and I seem to recall hearing that they put bitrex in, but since I don't want brain damage or liver failure, I've not tasted it to find out.)

If there's something you need a license for, perhaps it's denat. alcohol which doesn't have dye in it? That'd probably be your best bet, since I'm guessing you don't want your wood tinged pink and it's likely that the dye doesn't evaporate so quickly as the alcohol and may be deposited when the alcohol goes.

I've not tried the drying method myself, but I expect it probably works (if it works!) because the alcohol displaces the water in the fibres of the wood, but since alcohol is much more volatile than water and has a lower boiling point, it'll dry out of the wood quicker than the water would. Isopropyl alcohol is readily available - I've bought litre bottles from high street chemists before for thinning airbrush paints - but sometimes it's diluted with water, so I guess it'd be worth checking that first.

 

[CHJ]

Yes meths performs exactly the same function.

Tried it for a while and got all excited about the reductions in drying time.
Then came to my senses when I found that given better selection of drying location I was only gaining a week or less, far more productive to just put the pieces aside and let nature do the fiddling.

Does tend to result in a harder more brittle wood than if left to air dry naturally.

The wrapping in paper to skew the drying parameters is the more useful aspect of the method to reduce splitting.

Another example <<< link.

 

[monkeybiter]

Hmmm.... I must say I'm [predictably] impressed by the finish of your 'rough turned' bowls Chas. I'd call that done and stop while I was ahead

 

[midge29]

thanks for the information on that , so if soaked in the meths with the purple dye would this dye the wood , as i have read it is the clear stuff that a license is needed for

 

[CHJ]

thanks for the information on that , so if soaked in the meths with the purple dye would this dye the wood , as i have read it is the clear stuff that a license is needed for

No significant change in wood colour, certainly nothing approaching the shade change that occurs when normal finishes are applied.
I think you will find that the dye in meths is not light fast anyway.

Soak a piece of white paper in meths and let it evaporate to get an indication of colour concentration.

 

[finneyb]

Another drying 'solution' I've heard about is to put clingfilm across the top of the bowl. I assume it works by increasing the drying time much as paper bagging thereby giving the internal stresses more time to dissipate hopefully leading to less cracking. Never tried it, too lazy - I just throw the roughed out bowl in a dark place and come back in 6 months - but the turner that suggested is a no beginner and I think he uses it.

Brian