Dyeing bookbinding leather

[schuetz1619]

I am working with undyed veg-tanned goat, calf, and kangaroo (my favorite). I am trying to find a technique for dyeing these leathers that will produce an even color.

I've been using Fiebing alcohol-based dyes and get splotchy results even though I wet down the entire skin evenly in advance with 100% ethanol or 99% isoprophyl alcohol and dye the skins in two or three stages.

Any suggestions would be appreciated.

I've never used water-based dyes and would appreciate any thoughts on advantages/disadvantages from people skilled in their use.