Can you plunge an endmill longer than the cutting edges?

[trialanderror]

say you have a 10mm diameter end mill that is 7cm long. The cutting edges only cover 3cm of the length. If your drilling a deep pocket, will it matter if you exceed 3cm depth with this endmill (will the round part of the end mill cause problems since its not cutting anything?)

[mcphill]

It is fine to plunge deeper. Obviously you can't travel in X/Y deeper than the cut depth, though.

[rowbare]

Your terminology is confusing. Are you milling a pocket or are you drilling a hole? If you are milling a pocket, clearly you can't go deeper than the flute depth in one pass. If you are drilling a hole, you have to be mindful of chip clearing, they have no place to go once the flutes are buried. It won't take a lot of chips to bung things up at that point.

bob

[fizzissist]

say you have a 10mm diameter end mill that is 7cm long. The cutting edges only cover 3cm of the length. If your drilling a deep pocket, will it matter if you exceed 3cm depth with this endmill (will the round part of the end mill cause problems since its not cutting anything?)

I can think of lots of bad ideas, and this is definitely one of them.

A. No where for the chips to go.
B. If there is ANY runout at all....guess what happens.

If it works, it's because you're lucky..... not because you're a good machinist.

[txcncman]

I can think of lots of bad ideas, and this is definitely one of them.

A. No where for the chips to go.
B. If there is ANY runout at all....guess what happens.

If it works, it's because you're lucky..... not because you're a good machinist.

+1

Bad machining technique/practice.

[juergenwt]

Try to get an 10mm Endmill with a 8mmn shank or - relief the shank for the distance needed and keep the rest of the shank at 10mm or- buy a 10mm Endmill with longer flutes (look in a catalog).

[trialanderror]

It was actually contouring but did not mill all the stock, there were a few places where the stock was still there (acting like a pocket)

I actually did what my name suggests and tried it out and it worked perfect. I think the round top of the endmill got shaved .001 mm by the top of the stock as it went down but that wasn't an issue as the stock cut smoothly. Will invest in a longer endmill for future use.