Swapped from a standard collet to a hydraulic holder on our 40-taper Haas

We were getting chatter on a long 3/8 inch end mill doing deep pockets in 6061. My lead told me to try the HPI hydraulic holder instead of our usual collet chuck. The difference was night and day, the finish went from rough to mirror smooth in one pass. Anyone else have a go-to tool holder for tricky aluminum jobs?

3 comments

3 Comments

the_anthony3mo ago

What length was that 3/8 end mill you were running? I've had good luck with shrink fit for anything long and skinny in aluminum, but I'm curious if the hydraulic holder is better for really deep reaches.

the_val3mo ago

That one was a 4 inch reach, 6 inch overall length. Shrink fit is great, but for this depth the hydraulic holder really cuts down on the runout at the tip. The dampening helps a lot with chatter on the long flute section too.

ivan_perez2mo ago

That "cuts down on runout at the tip" part makes sense. A buddy tried a hydraulic holder for a deep 3/8 reach job and said the chatter almost disappeared compared to his shrink fit setup.