Dying leather = gigantic mess!

I try to put off dying leather as much as I can. It is so messy. The bottles do not seal very tight, but they need to be shaken extremely well, otherwise the pigments in the bottle are not even and you can get different results each time! This is the problem I have been struggling with over the last few dye batches. Certain mixes will turn out too dark, or too uneven than the last time I did it. Dying leather is a complicated business and it is so time consuming to prep all the leather pieces for dying. So you can see the frustration when things don't turn out how they are supposed to! There are so many factors that go into what the color will turn out to be. A few, but not limited to are:

• natural hide color: this can darken naturally if left out in the sun or even out on the kitchen table for a few days!
• solvent in the dye: if you leave the cap off for awhile, the solvent in the dye will evaporate and affect how dilute (or concentrated) the solution is.
• the amount of dye that goes onto the leather piece
• how well-mixed the dye is
• humidity: affects how fast the solvent evaporates after being applied to the leather, aka how fast it dries
  

Too light of a brown shows blemishes on the leather, but too dark of dye looks black and does not have nice, rich brown tones. To combat these problems I have been having, I decided to get more "scientific" about this process, I am a chemist after all! OH not to mention that when the dye gets on your hands, it will be there for the next few days- and I mainly work with browns and blacks...hmm. Anyways, I got some syringes and gloves to use for this next time and tried mixing some "formulas". I did three new mixes, wrote all the amounts down and tested it on some leather scraps. I liked how two of them turned out, but tweaked them just a bit. So tonight I have dyed some real leather pieces and we'll see how they turn out compared to my "test" pieces. It takes a good 5+ hours for the pieces to dry completely, then they need to be conditioned and sealed before the true color really shows. All in all, starting from a natural hide to the dyed and finished pieces is about a 3 day process! Whew! well keep all fingers crossed that this batch will work out, otherwise it will be another week before I get a new batch finished.