Hi everyone,

I'm planning my first Raw Inventive 2.5 build and would appreciate some advice before I start ordering parts.

My intended machine size is relatively small, around 750 mm × 750 mm overall dimensions, and the primary use will be guitar building (acoustic + electric)

fretboard slotting

inlay work and rosettes

truss rod channels, maybe neck carving

body shaping + pickup cavities

templates, moulds and jigs

I do not expect to machine aluminium, at least not regularly. The machine will be used mostly for wood, hardwoods, plywood and occasional plastics.

I already own a complete NEMA23/TB6600/Mach3 electronics kit, so I plan to use that.

I have a few questions:

1. Ballscrews vs Timing Belts

For a machine of this size and intended use, would you still recommend ballscrews over timing belts?

I'm interested in good repeatability and accuracy for fret slotting and inlay work, but I'm not running a production shop and cutting forces will be relatively low.

For those who have used both systems, is there a noticeable real-world advantage to ballscrews for guitar work?

2. Makita Router vs VFD Spindle

I'm debating between a Makita trim router and a VFD spindle.

For fine work such as:

fretboard slotting

small inlays

detailed engraving

is the Makita's runout a practical limitation?

Would I actually notice a difference in accuracy or finish quality, or is the main benefit of a spindle reduced noise and smoother operation?

If you were building this machine today specifically for lutherie work, what would you choose?

3. Steel Plates vs Valchromat

The plans recommend steel plates, which I can order, but I already have a substantial amount of 19 mm Valchromat available.

Given the relatively small machine size (750 × 750), would 19 mm Valchromat be a reasonable alternative for:

gantry side plates

Z-axis plates

carriage plates

motor mounts

provided that it is properly sealed and reinforced where necessary?

Has anyone built a smaller Raw Inventive machine using Valchromat or another engineered wood product for structural plates?

If so, were there any issues with rigidity, long-term stability, or mounting rails and bearing blocks?

I'd love to hear opinions as well as feedback from anyone who has built a similar-sized machine.

Thanks in advance!

Saïan