450x300 Aluminium extrusion build from scrap/used parts

[Nealieboyee]

Hello boys and girls,
After a long long time of promising myself to build a machine, I'm finally going to do it. I hope to mill/cut plastic, wood, and hopefully some aluminium up to 6mm thick. Accuracy I'm aiming for is around 0.1mm if possible.
Here is my machine plan. I would love some constructive criticism.

Specs:
Y-axis supports are 40x80 extrusion.
X-axis gantry is 80x120mm heavy duty extrusion.
Gantry side plates are 10mm aluminium plate.
machine base is a tooling plate of 10mm aluminium. It has a few holes here and there, which I've modelled in sketchup, so excuse those please.
Final working area is around 440x280mm, but if I can find a bigger base plate, that would be great.
Motors: I'm not sure, but probably around Nema 23 size, perhaps 4Nm?
Rails will be 20mm Hiwin, or Chinese, depending on price.
Ballscrews will likely be 1605.

Would someone be so kind as to critique my build please? :) Note that I haven't included the ballscrews for the x and z axes yet. Still working on positioning those. Ideas?






Thanks all :)