Originally Posted by
SSN Vet
From my perspective, the key ingredient to any machine purchase or build is to have a clue what your want to do with it.
Many DIY types (and I'm certainly a DIY type of guy) have never operated, observed or seriously talked to anyone F2F who is running a CNC machine for any commercial application. They see a couple YouTube videos and think, "I want to do that" and then they're off to the races to build Joe's 2006... and are disappointed to find that they can't machine AL on it.
The idea of cutting forces escapes many and while pushing a router bit through sign foam has next to zero cutting force incident on the tool, Hogging out 1" MDF in a single pass at 900 ipm is another matter.
My contribution to this discussion is that of economics.... with the Chinese pumping out decent quality linear bearing kits and ball screw kits in high volumes and selling them for on e-bay for very short money, I suspect that the 80/20 linear motion ideas, made in short volumes will likely cost more and deliver less.
Just my 2 cents.... worth exactly what you paid for it.