Wobblycogs CNC Mk2

[Wobblycogs]

I've been having a look at the control / motion side of the machine for the last week or so hence the lack of updates. I think I've now settled on a fairly uncontroversial set of components but I'd be grateful if someone more experienced could have a quick look over the shopping list...

• Steppers - 4 * Nema23 3.1Nm, CNC4YOU
• Drivers - 4* AM882, Zapp - Is there a reliable cheaper source?
• BOB - PMDX-126 Rev C - I plan on using the Rev B slave feature for the X-axis.
• Spindle Speed Control - PMDX-107 - Unlikely I'll set this up straight away but might as well get it now
• Step Generator - Ethernet SmoothStepper
• Software - Mach3 - Might wait till Mach4 as it looks like there won't be an upgrade option.
• Stepper Cable - 4 Core CY Cable 1.5mm^2
• Spindle - Spindle 2.2kW with VFD
• Computer - One of several spares kicking around the house, running Win XP probably.
• Power Supply - Currently planning a self build...

Total cost:

I plan on adding limit switches, water cooling pump, radiator, etc but I think this will get me started. I could do with a recommendation on cable for the spindle though

Most of the machine will be bolted together with M4 cap head screws, will this be strong enough? I settled on M4 rather than M5 to get additional threads in to the aluminium box section. My gut feel is that with the number of bolts I'm using either would be fine but I don't want to go buying a million M4's only to find they are the wrong size