If you visit the above link, you can watch this gal (sadly, not Juli Haas) drypoint away with her very sharp & heavy tool. FYI - "Perspex" is Brit speak for Plexiglas. Diamond tipped tools are best, with carbide-steel running a close second. Too bad that drypoint plates have a limited short life. The best prints are the very first ones, & the plate will only hold up for about 10 - 15 impressions.