Linear Rail derivative with ball screw

At this stage very much just CAD progress drawing and mochup rough design.
Just trying to work out bill of materials and overall sizing of machine work area

Goals:
reliablility
machinable area min 500x600x100
sturdy, minimum flex
budget: cheapest as possible while not skimping on quality parts where needed
bed area enclosed for cooling/liquid containment

Materials wanting to use:
ballscrew 1605 + components bk12,bf12 etc...
VFD controlled 2.2kw water cooled motor
48volts supply
387 oz.in Bi-Polar Stepper motors
Geckodrive G540 controller

Plan to look at misting/ fogbuster or equivalent system



Update 1: 6/9/17
change to linear rail, possible looking to swap from 1605 to 1204 for smaller components
dimensions
x 1092 overall
y 1000 overall
z gantry 275x90x10, x axis cbeam250
need to adjust offset on gantry endplates for spindle, just dont know what it needed to be at this stage....

x,y rail ,mgn15h 1 block on each rail
z rail ,mgn12h 2 blocks on each rail 4 total

still need to add new ball screw and endplates etc



Update 2: 18/9/17

gone with 1205 ballscrew
as we sit dimensions dropped to account for easier use of parts availability
bed 800x760 may change to account for ballscrew rod a little odd length, still need to work out with bearing blocks.
z clearance 100mm from lowest point on gantry, so depending on tool may have 85-90mm z height