Hello, i've been following this forum for a while now because of my eagerness to build a cnc myself, after much searching and "studying" i've concluded to build a rectangular moving gauntry design 1150mm (y axis) by 1000mm (x axis) and 400mm of z axis, i will be using 40x40mm aluminium profile for the cnc Y structure, 80x20mm aluminium profile for the x axis, the 80x20mm extrusion will be between the two plates of the gauntry, i still need to figure out the design of the z axis though.
Anyways, i would like some opinion, if possible on some subjects regarding this build.

-First of all, do the aluminium extrusion sizes seem adequate?

-Second, for the gauntry plates do i use aluminium solid plates or can i make them out of aluminium profiles too?

-And third and most important, these are the rails/screws i was thinking of using for my build:
-2xSBR20 rails 1150mm long with 4pcs respective bearings; (Y axis)
-2xSBR16 rails 1000mm long with 4pcs respective bearings; (X axis)
-2xSBR16 rails 400mm long with 4pcs respective bearings; (Z axis)
-2xRM2510 ballscrews 1150mm long end machined with 2SETS respective support bearings BK/BF15 and nuts; (Y axis)
-1xRM1610 ballscrew 1000mm long end machined with 1 SET respective support bearings BK/BF12and nuts; (X axis)
-1xRM1605 ballscrew 400mm long end machined with 1SET respective support bearings BK/BF12and nuts; (Z axis)

i shall purchase these items from "our friend" linearmotionbearings2008" as it seems to be the best for my budget.

So, does this build seem ok? are the rails/screws too small for the X and Z axis, as they are smaller than the Y which needs to be the most rigid axis?

Thank you very much in advance, any help is crucial