Is there anyway to dye nylon or dacron?

Question

I want to make a tie-dyed sail for my boat and those are the only two feasible materials to use....

Answer 1

man, that would be cool, i never thought of it. it though can be done but it is beyond the normal do-it-yourself-er as it takes special equipment and dyes to do it. the fabrics you describe are basically plastic so the colorant has to be forced into the material.
this is usually done with acid dyes, high pressure and heat. see if there is a local dye house that does piece work in your area.
good luck and hope to see your hippy sails on the lake soon.

Answer 2

Honestly, no. These are synthetic materials and won't hold dye.

The only way around this I can think of (and I know absolutely nothing about sails, so sorry if what I suggest is ridiculous) To start out with a cotton and/or any other natural material, tie dye it then somehow treat it with something to make it act as if it is nylon, etc.