Yeah, that's what I put it down to as well ...................... he really could of done with an extra 100mm or so on the Y axis gantry. But no doubt decided to stay with a standard 1000mm set up. I'm working on a similar design but both my uprights will be on the outside of the Y axis rails. I like this idea as it has a lot of depth to it ( like the base is a box section if you like ), as I'm working with three dimensional forms I can lower my work piece and sit it inside, and have the top of my work piece level with the bed. TURK