Re: homemade varnish remover
Lye + starch (corn starch, usually) is a home made stripper for paint, etc., But I never heard of dye.
Lye is of course extremely caustic, and burns skin on contact, and requires a lot of neutralizing before you can repaint. It also burns the wood fibers, and causes the wood to change color. Pine turns greenish, oak turns dark brown, and the color is permanent.
You mix the starch in to thicken it into a more pasty consistency, otherwise it is thin as water. The heat from the exothermic reaction of lye + water cooks/thickens the starch. I have only used this recipe once, in an attempt to remove grease stains from stone, with limited success.
HTH, but I advise against it in the strongest terms.
Remove not the ancient landmark, which your fathers have set.