Every now and then I have to make a small batch of rosettes in the machine shop. I normally don’t do this on this Bridgeport because I don’t want the dust to get on the mill. However, I did today because I had to do a little work on the small mill. We have a couple of other machines to do these in bigger quantities but this is just as good a way as any to do them in quantities of 50 -100 pcs.
The other reason that I prefer to do this on the smaller mill is because the highest speed on the Bridgeport is around 2700 RPM where as the smaller mill made by grizzly has a top speed of 5000 RPM.
We use a head made by Charles G G Schmidt that has a max RPM limit of 7500 RPM. We grind and sharpen the knives in our grinding room. However, the one thing that I insist on doing myself is to put the knives in the head myself to make sure they are inserted properly and that the retaining screws are tight. This is for an obvious reason. The centrifugal force is relatively large and if one of these knives comes loose the force will throw the knife out at a speed that is high enough to go through a man’s body.
Everything so far has worked out fine but that is because I always try to be careful. Someone was killed by one of these heads in a small shop a while back because someone foolishly put one of these heads in an overhead router at 20 or 30 thousand RPM. One of the knives flew out and went straight thru the mans heart and out his back and he was killed instantly. The reason that MAX RPM is stamped on a cutter head is so that people will not be killed or injured. Please, folks, don’t foolishly neglect things like this. The laws of physics are real and the warning notice is there for a reason.
-- If a man does not keep pace with his companions, perhaps it is because he hears a different drummer. Let him step to the music which he hears, however measured or far away. Henry David Thoreau