"Routerman P. Warner" wrote in message
om...
These small motors often resonate with long and or large diameter
cutters.
It is not uncommon. I have seen it in all small routers, the DW 621
being the most tolerant. If ever you fire the switch and the router
starts vibrating:
Kill it or slow it down imediately.
Http://www.patwarner.com (Routers)


As usual excellent advice but I think you may have misread as I did the
first time the size of the bits that are giving the problems. The 1/2"
shank bit is 2.5" long, that is really not too long and it only cuts a 1/2"
wide.