I experienced the dreaded tool pullout (end mill in ER collet) twice last week when making some Tee nuts.
Yes the chuck was very tight, yes the collet bore & end mill were clean & dry, etc.
Luckily the stock was from my bin of chinesium, whoknowsium and some pyro777, that's the stuff that produces a beautiful pyrotechnic display directed straight at the operator with the sole purpose of causing pain & suffering, regardless of what speeds & feeds are used. ( I am fairly new to this milling thing in case the penny wasn't heard"

As a consequence, I now have far less trust than I previously had for end mills,
and very soon I want to remove a strip of metal about 32mm wide, 7.5mm deep, to a length of about 450mm from a piece of heavy 1020 bar prior to cutting dovetail along that length.
Given that it cost me not much shy of $100, I don't want to have it buggered up like the Tee nuts, so would prefer to use a different tool if possible/practical. Doesn't matter if it take longer to do than end milling.
I was thinking I could set it up on it's side and use a slot cutter, of if that is not a good idea, perhaps make a very small fly cutter? Suggestions appreciated


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