I have a DF500 and everything was working fine, then earlier this week I broke a 5 mm cutter on some white oak. I bought another one and within 15 cuts it broke the tip too. Festool is standing behind the cutters, so that is good, but then today I was using it again with a 10 mm CMT cutter and it broke the tip off too in popular, so very soft wood. I'm plunging it slow and smooth. After the 10 mm broke I noticed a small screw on my workbench that looks like this... Any ideas on the issue? Thanks. [/img]