I had not even thought about the wood hardness, thanks for that.
Let me ask then about wood such as Mesquite. I would like to make some knife scales, animal calls, and revolver grips from Mesquite. I have a lot of it on my place and some of it is really nice. With a wood such as Mesquite, how much penetration might I get? Does anyone stabilize Mesquite?
I know it is dense and may not need to be stabilized (need being debated by many).
Well, there are other factors that will affect/determine how much CJ will penetrate, and they are natural wood oil, resin, silica and how dry/free of moisture the wood is.
Yes, one could agree or disagree about the need to stabilize Desert Ironwood and Mesquite type woods however you make that decision and I can tell you that you can stabilize pen blanks, knife scales or blocks not of excessive thickness, you get a better result but cutting your blanks to the sizes you need and not a big chunk for later to slice out.
The are 2 of the stabilization steps that I will bring to your attention to achieve satisfactory results with that dense wood, make sure you oven dry it for a couple of days at 60° Celsius, make sure the wood is well covered with CJ, let the CJ stop forming any bubbles when under vacuum and most important step, after opening the chamber's lid, make sure the CJ still cover the wood well and let it stay there for 24 to 48 hours before curing it in the oven.
Good luck.
Cheers
George