Im enlarging some 1/4" holes in the lower inside door portion of a Roadmaster to fit one of my rust proof wands in. all goes fine then several minutes in the die grinder starts bucking. This is nothing new had it many times over the years. I use those endless assortment of carbide end mills of different shapes. In this case started out fine then after a bit the bucking began,. ive tried changing direction and lighter cuts heavier cuts, have a very tight grip of the beast but still wants to skip and bang and rattle all over the place. I dont see any clogging either. Im doing light steel whatever thickness they used on these 96 bodies. It used to happen with thicker material as well though so. Sorry if this is in the wrong place, move me if there is a column for bucking die grinders