New and in need of wisdom

[JAZZCNC]

It would seem that I need at least 2 machines to cover the range of materials I work with: CNC router for softer materials up to say 6061 T6 (will a router style rig handle this grade?) and a Mill for 7075/Steel work.

Yes and NO.? If steel then YES you really need a milling machine. . . .BUT. . . If you choose a different design router style that doesn't use long gantry sides but instead has strong frame with high sides which the X axis rails sit directly onto so gantry pretty much sits directly on the bearings so reducing flex and handling resonance's better. Along with driving the gantry from both sides with twin ballscrews then coupled with raising or lowering the material near the cutter either using a adjustable bed type system or just putting in tempory raising blocks you'll be able to cut a vary good range of materials right upto 7075 aluminium. Obviously you'll still need a decent spindle for this a run of the mill wood router won't cut it.

You could also build a fixed gantry style machine which tend to be slightly stronger design.? It just requires more working space for the same cutting area.

Search the forum and you'll find loads of references from Jonathan and me regards this type build has it's one of the few things we agree on.!!

When you say "stronger" would this mean replacing many of the extrusions (especially on the gantry) with aluminium plates, upping the size of the ballscrews and supported rails?

I have already lowered the Z axis, widened the spacing on the Y axis supported rails and added in two ballscrews on the X axis - any other areas I should look at and should I look at flood cooling from the outset?

Has I suggested above it would be a completely different design really but would or could still involve profile and alu plates. Regards upping size of ball screws and rails then no that's not required and can actually be detrimental to machines performance if too big.

Flood cooling is always good idea but when cutting Aluminium then blown air works very good, esp if used with a misting system.

Software - CAD isn't a problem, so no worries there. CAM/toolpath software I have seen is the Vetric stuff and VCarve Pro appears to be what I need (I've also been playing with Cut3D already just to try stuff out) the and Mach 3 for the machine control? Any others out there?

Oh and cutting carbon/glass re-inforced resins and plastics - can this be done, as I also do some composite work?

All those you suggest are OK for wood and v-carving, engraving type work but you may want to look at others that are more suited to engineering type.
The difference comes mainly from the 2D & 3D tool-paths they provide which tend to be more suited to milling metals. Things like Drilling, boring, chamfer, thread milling cycles. They also tend to come has standard with more material entry options, things like ramping, contour ramping, spiral, parallel roughing etc.
3D tool-paths tend to come with features like advanced roughing, pencil, flatlands, equidistant offsets etc

Bobcad cam, Dolphin, Mesh cam and even Cambam I believe offer some of these options and his quite cheap.
Personally I use Bobcad cam for most of my basic mechanical metal type work and Artcam for the more Art'y stuff like Engraving, V-carving and general wood/plastic type work.
Really there hisn't one software that does all aspects best so you may find your self using a few different software's depending on what your doing.?

Apologies for the flood of questions,

Don't Apologise and keep asking untill your 100% happy and understand. Esp ask before buying components if your not 100% sure.