The reason why I don't use solid metal is because of cost and logistics. I cannot spend more than $1000 on the frame and I also don't have a garage nor a car (college student rip) so that kind of limit my choices (everything has to be delivered to my apartment and fit inside an elevator). It is also nearly impossible for me me to carry 300 lbs of steel to the machine shop at school so I prefer to keep individual components relative small. I found out that using 1/4" steel plates to create a box achieves similar results as cross beams while being cheaper and easier to manufacture. All I am looking for is some sort of numbers that would even remotely reflect real world performance, like is 1 thou deflection at 150lbs load good, bad, or terrible? It is impossible to me to design a machine without knowing what loads it will take. I'v also redesigned the gantry a little and now it uses angle iron which are much cheaper, deflection still sits at a little over 1 thou. (https://drive.google.com/file/d/1dQ9...ew?usp=sharing) The gantry is about 10"x10". Does it look like it will work?