I've wanted to build one of these for a while, and am finally getting around to it. I intend to use it for planing solid bodies, as well as archtop & acoustic tops/backs. I found some CNC rails & linear bearings on eBay. The sled itself is made from 16ga. steel plates with 3/4" cabinet grade plywood spacer sandwiched between. The table measures roughly 36" x 48". I'll build drawers & shelves underneath to maximize all that space I'm taking up in my shop. The bit is 1-5/8" diameter, which ought to cut down on the amount of passes I'll need to make. I need to find some brush type material to put around the sides (to keep sawdust contained), and I still need to install the T tracks for holding material down. Hopefully I'll get to test it out soon!