Quote Originally Posted by Doddy View Post
Start with a more forgiving material to begin with to get used to the machine - a bit of brass would work well. Dial that in to understand what your machine can do (and there are limits that it will achieve with backlash and rigidity inherent in the build of the machine). If you can't engrave brass well enough then don't even go near silver. Another material to play with would be PCB blanks - SRBP - cheap if you can find it).

You might want to look at the micro mill bits (google for end mills with e.g. 0.3mm diameter cutters). These offer the advantage that the cutting edges are parallel - rather than tapered - which means any variance in the height of the material, or movement in the spindle height (flex in the machine, flex in the bed, material thickness) will be less pronounced than using a tapered engraving bit. Watch out though - the bits aren't cheap (~£10 each) and will snap if you so much as look at them).

Be realistic.

From a 5 minute read silver sounds horrible to machine.
Thanks for info :o)

I've been practicing on ally and managed to get some half decent results but not good enough yet... Been using carbide v bits 30 degree x 0.3 and 60 degree 0.2. Had some v bits that came with the machine and these did ok on some carbon fibre I tried but blunted really fast on ally... The carbide ones are more robust for sure and I've managed to cut ally. Only using v bits because I want to do quite small fonts (5mm high) and I'd need a 0.1 end mill to do that the software tells me... and even though I have very limited micro drilling experience I just think there's NO WAY that wont break on the first go! BUT the v bits aren't cutting as clean as I'd hoped... :o(

I guess I was hopeful simple engraving could be done after seeing this video... https://youtu.be/QuM6Ic1Cxok I realise the Nomad is a MUCH better machine but he's using a v bit and only 10k rpm on Silver. He gets a pretty nice cut on the harder silver.