Methylated, also called denatured, alcohol will darken wood, leaving a brown tint. So do not use it
You may have just told me the reason why every time I de-oil an old stock in acetone, then denatured alcohol, the wood always has a grayish look to it after drying. Can I prevent that by using surgical alcohol ?
I was under the impression that it was just because the wood was so old. It never looks anything like "new" walnut.
SRH
P.S. Is surgical alcohol the same as isopropyl alcohol?
The term "surgical alcohol" does not have a chemical meaning. I looked it up and it generally refers to rubbing alcohol which is a mixture of (generally) isopropyl alcohol and some oil. It does not mean ethanol.
Denatured alcohol is ethanol (drinking alcohol) that has stuff added to it to make it undrinkable.
They used to add methanol (wood alcohol) as the denaturing agent and that product was often called "methylated alcohol" or "methylated spirits"
Drinking methanol can blind you or kill you so they don't use it anymore to denature alcohol. Instead they some other agents that just make you sick. I don't know what the various denaturing agents in current use are but it is likely that they, and not the alcohol, are causing the graying you see. I have used methanol extensively for decades and have never had it gray anything.
Is your graying so dark that it makes staining difficult?
