Quote Originally Posted by JAZZCNC View Post
You don't have to take my advice and by all means go for the larger screws etc but you will regret I guarantee you that.!!

Your doing the classic BIGGER IS BETTER approach and that's a sure fire way to waste money and build an under performing machine. Digital drives won't make any differance if they are sized wrong and mismatched to screws.
Even with the stuff I suggested I recommend you use Digital drives but this as nothing to do with giving more power but more to do with being smoother running and resonance handling capabiltys.
I understand what you're saying- I have received advice saying I should get large screws on my X,Y and Z and I should get 800w digital drives... But here, collaborative experience dictates otherwise...

as for the bigger is better approach; no, I just want a good solid reliable machine and I'm willing to invest the time and effort in researching the best equipment - you guys seem to know what you're talking about, and I'm just trying to understand the reasoning behind, which for all intents and purposes you've so far done well to justify.

My general philosophy when it comes to building stuff is to keep it simple and functional, I hate things that are over engineered unnecessarily.

So with the machine, I would like to use only the best possible parts for the required cutting area and material.

based on what you've told me (and off the top of my head)

profiled rails are best on all axis.
20mm ball screws on x, 16mm on y and z.
the ball nuts should be reinforced more than I have.
the position should be better placed, to avoid chips and being knocked
i should use digital drives correctly sized and I should not get poor motors with high inductance. (Have to get the maths out for the lads!!!!)
the bed should be adjustable, so when I cut alu, I should be as close to the y gantry as possible.
to help reduce resonance, I should use pullies this will also enable me to adjust ratios...
pitch on the ball screws should be 10mm on x and y and 5mm on z...
And dont waste money - unless I really want to ;)

did I miss anything?