Hi, this is my first post and I'm looking for some basic advice. I'm just starting out with my design and I plan to build a 4'X8' router. I am using the shopbot prs as my inspiration and will be using a two motor drive for the X axis on a rack and pinion setup. The Y will be a one motor setup also implementing an R&P drive system. As of now I would like to use a premade Z axis from K2 routers www.k2cnc.com which incorporates the leadscrew drive off a NEMA 23 mount. First off, can you incorporate these two different drive systems together and adjust the difference in lineal ratios with the controller software? I realize that I will need a geared reduction on both my R&P axis and I plan on using some sort of planetary gear box that mates directly with the steppers. Any ideas on reduction ratios? I'm not looking for an ultra speedy machine and would rather error on the side of accuracy. My rough estimate on gantry weight is around 100-150 lbs depending on materials. Could I get away with NEMA 23's on the X and Y or will I need something with a bit more muscle? Also, any ideas on rack and pinion parts. I've seen Boston gear sited here occasionally. I think I will be using a PBC al extrusion profile (www.pbclinear.com) that has built in guide ways for both x and y axis. Any advice would be great. Thanks!