I have had success in the past using tamiya acrylics to dye polyester resin a muddy colour, but now i need something a little more transparent. I was thinking of using some water based drawing inks to get the desired effect, but i have a few questions;
1. Does water really ruin polyester resin, and if so what happens. How much water would it take to spoil it?
2. Do tamiya acrylics contain any water? This would clear a lot up for me.
3. If they don't then I assume that they use only IPA and other solvents, which i guess must mix with resin? Or perhaps i there was not enough paint in my last attempt to ruin it?
4. Will ordinary water based inks ruin the finish, even in relatively small amounts?
I am aware that special dyes are available, but i don't really have access to these.
Thanks,
Luke

I've used Tamiya acrylics, Revell/Humbrol enamels and artist oil paints successfully in the past to dye polyester resin from a muddy look to a 90% see-through look, it's just a matter of how much paint you add.

Hi Luke, i don't know the answer to half your questions, but indeed I would not use a water based tint for my resin, that would be like trying to miw water with oil you see. Bad idea.
I personally use some transparent oils, and honestly those do the tricks pretty well!
If you tried with tamiya paints and it worked with resin, maybe you should try tamiya transparent paints? who are some sort of tinted varnishes from what i can remind. But i never tried myself

thanks guys, i hadn't thought of oils before, but i have plenty of greens and blues to use. I will give it a try at the weekend perhaps.