So as the title says, I started a fire today with my Shapeoko XXL. Luckily we caught it pretty early and no extensive damage was done, and nobody was hurt. After cleaning everything up and some damage control, I’ve identified what happened, but I’m looking for reasons WHY it happened.
About a week ago I had an incident where the end mill started slipping out of the router and cutting all the way through my material and into the waste board. I quickly stopped the machine and figured I forgot to tighten down the collet. However, today I was sure I double checked everything prior to starting the job. About 1.5 hours into the operation, I heard violent grinding sounds and smoke coming from the shop. I quickly shut down power and put out the fire that was quickly growing both on the waste-board and inside my dust collection system. After cleaning everything up, I discovered the same issue had happened as before. The end mill had slipped out over 1" from where I installed it. The cutter was plowing through all of my material, through my waste-board, and even into the stock waste-board underneath. A spark was ignited from one of the threaded inserts, and sucked into the shop-vac. So far, I can tell the dewalt router is trashed, but I haven’t checked any of the Shapeoko electronics.
My question is this: how could my 1/4" end mill have slipped out of the collet even after tightening it down? Is this a common issue with the dewalt router? Was this user error, or do I have a defective router?
Any help here would be much appreciated. I’ll attach some images of the router and my stock after this all happened.