What the hell do I need ?? (humourous replies expected :-) )

[Greeny]

Hello Alan,

I too am a self build noob, with no track record so bear that in mind :-)
I do have quite a bit of experience with CNC in the glass industry though, both operating and programming.

Glass CNC is BIG stuff, you are talking 6 ton+ for grooving (brilliant cutting) and edgework (table tops, balustrades etc)
Stone machines are essentially glass machines with the word glass crossed out and stone written below

You will probably be ok with very light engraving on typical self built CNC machines, but as far as glass/stone goes that's about it.
The sandblasting we do is computer cut masking material stuck on glass and then Sandblasted in a cabinet. Other than cutting the mask i doubt CNC will help.

Wooden signs is absolutely bang in the zone for self built/low end commercial CNC routers.
They can produce some outstanding designs.
Many self built routers far exceed the quality of low end commercial ones. Of course some don't. lol (Prob mine)

As to build or buy. If you have the time then definately build your own.
You need to read and read and eventually it will fall into place.
You will understand the machine FAR more than if you bought it and be able to service and fix it yourself.
The cost both financially and timewise of relying on a service company to maintain and fix a CNC can be VERY high.

Of course if you don't have the time/confidence/inclination to build then you will have to buy.
If so be sure to ask about maintenance & ongoing costs.

Hopefully more experienced folk will be able to give more detailed advice.

Cheers
Greeny