You have to mill a slot or a wall deeper than the the flute length / reach of your end mill. That never happens, because the boss / management makes sure before hand when planning the job you will have all necessary tools - right? Here's all these nice carbide standard flute length end mills that are too short to do the job - go get'em tiger! Chuck it up in your cordless drill, go over to the pedestal grinder with the "green" (silicone carbide) wheel & turn down - extend the shank- a few thou less then the cutting dia. You chew up the green wheel & it takes a little practice to hold the drill & rest your baby finger on the grinder tool rest to hold every thing. Hey it beats setting it up in a spinner & using a diamond wheel in the surface grinder, or ordering one of the off the shelf special order extended length "mold makers" brands. My new record = 1mm dia 9mm dp. in titanium 6al4v -those little ones are tough.
A little deckel SO grinder would be nice. Nah that'd be like the "big red easy button"
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