Hello i am new to the world of engraving . I get a CNC from Stepcraft ( m700 ) and i take it to engrave brass ( wax stamp ) .I use a 3.175 mm . I using cutters like the ones that i attached. My main problem is that the cutters are broken everytime . I want to engrave like the attached photos . The wax stamp is 2.5 cm perimeter . Can someone tell me another cutter for such a detailed job ? The cutters i used are for hard material . Can someone help me with this ? I am using 12.000 rpms till now .Thank you in advance .