Quote Originally Posted by Ger21 View Post
99% of DIY CNC users don't use Cutter Comp, because they have their CAM software do it. That's why UCCNC didn't have it.
It makes sense. Its probably a function of how one uses a machine, what one cuts and one's expectation. If you run into material you haven't cut before, or a geometry that forces you into to a setup that isn't ideal, and the tool deflection creates an outcome out of tolerance, you can either lie about the cutter diameter in cam, re post and rerun it. Or make a quick radius comp and rerun just that section. I think the latter is baked into most machinist's habits. The former has become perfectly reasonable beccause cam has become nearly ubiquitous at all levels, even in the home.

Quote Originally Posted by Ger21 View Post
As for the Lookagead. There's a lot more to it than just how many lines it looks ahead. Different controls have different methods to determine how they follow the commanded path, and how much they are allowed to deviate from the path. The trajectory planner can make or break a control. If I had to guess, I would expect the Centroid planner to perhaps be a bit better than UCCNC's, because it's been around a LOT longer, and it's been known as a higher end control. But I also know that UCCNC's planner is much better than Mach3's.
Interesting. I played around with both mach3 and UCCC, and I couldn't get along with mach3 at all. Not sure why, but UCCNC seemed way better thought out. I could make things happen immediately. Speaking of lookahead, for my day job I sell Okuma machines, and its amazing how they do it. The look ahead is infinite... the entire program is calculated. The other part is that the tolerance is adjustable, both by a dialog page or in the g code itself. Giving the cutter path more tolerance makes it more aggressive in corners and cycle times speed way up. Think roughing a mold, where 0.020" is left everywhere. There's no reason to hold tight tolerances, and time is money. Then for finishing passes you tighten up the tolerance and the acc and decs get less aggressive accordingly.