Tried dyeing my s28 and s29 again, this time with nearly half a bottle of brown dye and some red dye as well, and these were the results-
This one (s28) turned out very nice in terms of even coverage. The dye went onto the figure nearly evenly with no obvious splotches. It seems like using a lot of dye rather than dunking the figure over and over again into diluted dye works best.
I wanted the s29 to be dyed darker than the previous one so I left it in the pot longer. The dye didn't go on as evenly, but I assume this will probably disappear in a few days. What's interesting with this figure is that I had previously painted some nipples with a mixture of silicone caulk and oil paints, and I was curious to see what would happen with that in boiling water. Turns out it didn't ruin the paint at all.
Before-
https://i.servimg.com/u/f39/20/08/92/87/paint311.jpg
And after-
https://i.servimg.com/u/f39/20/08/92/87/paint810.jpg
HOWEVER, I did notice something troubling with both of these figures. This is the third time I've dyed both of these figures in boiling water, and it seems like repeated dyeing sessions does start to have some effects on the quality of the figures.
The s28 had a little tiny bubble appear on the thigh. I had noticed a little bubble or two on my s12 that I dyed earlier as well. On its own it's not a huge deal but I suppose if you try to dye your figure frequently eventually more of these will start to appear.
A bigger problem I noticed was the silicone tearing in the groin region. The s29 got it pretty bad, and the s28 has it somewhat as well. Now I didn't check back when I first started this whether these figures had tear before I began or not, but I definitely don't remember the one on the s29 looking as bad as this.
https://i.servimg.com/u/f39/20/08/92/87/defect11.jpg
Not a big deal if your character is wearing pants obviously, but something for people to keep in mind. It seems like the best way to dye the figures is to do it once in a pot with a lot of dye in it, like the way that Titan did earlier.
I still want to try dyeing another figure though. Next time I'll try dyeing a brand new one using a lot of dye, and see how evenly it goes onto the figure and whether or not it fades. That experiment might have to wait for next month though.