Hi, I'm in the aluminum-milling router design process. Desires for rigidity have led me to a fairly large gantry, 200x150x12.7 steel tube, which plus the Z axis will weigh 80-90 kg. I'll be using a granite surface plate as the bed, 600x900x100, which weighs in around 190 kg. There will be a stand support, which might weigh another 50 kg or so, but it got me to thinking: what is an acceptable ratio of mass between table and gantry? I'm only planning on cutting around 2000 mm/min with rapids at 5000 mm/min, but if I go faster with servos, at what point does the gantry mass cause problems relative to the table mass?