Hi Joe,
The Offset for the V-carving operation could include a negative offset of a thousandth or few if you thick narrowing the plug a tiny bit will make a better fit. The steep cutter angles are just going to be less forgiving with any kind of tolerance/precision, and as I mentioned previously they will make it difficult to have small details and features depending on the wood and how well it can hold up to having thin narrow features. I don't think I'd ever attempt such a steep inlay! A 60 degree V-bit is probably the narrowest that I'd be comfortable going, for a 30deg taper on the plug, largely because of how flimsy and unreliable my machine is. With an inlay I need all the help I can get to make sure everything will fit together :P
- Charlie