So I've been kicking around for a while in my head mixing a little ground up charcoal into my borax. In theory it might add a little carbon to the mix, or at least keep the decarborization to a minimum. The mix I came up with is about 1 part ground charcoal to 5 parts borax. The 1st blade pictured is done using this flux, the second is standard borax. The etch is a little different. I'll do some more testing before I call it beneficial.
Rule #10; "I can make that" translates to; "I'm to cheap to buy it new."