Re: [CAD_CAM_EDM_DRO] Re: Best benchtop 3D CNC milling machine

Andrew Werby wrote:

>[By "high speed", are you referring to the spindle speed, the feedrate, or
>the whole process? True High Speed Machining really can only be done with a
>very rigid and heavy Vertical Milling Centers- the kind that are enclosed in
>a shower-stall type closet, so coolant can be blasted at the part without
>making a big mess. They have very powerful spindles too- in the 5hp and up
>range, and cost upwards of $50,000. Benchtop machines, much as I love them,
>are not really in the same league.
>
>

Yes, I read a book on high speed machining. The grand finale was a
report by a group at Boeing,
I think, that had modified a Cincinnatti gantry bed mill with a 75 Hp,
75,000 RPM spindle.
The were running a 1/2" end mill at 75,000 RPM, and used up all the
spindle HP when they were
removing aluminum at a rate of 600 Cu In/minute! They did not use any
coolant, as the whole
idea of high speed machining is that the WORKPIECE becomes the coolant!
The spray of chips
from this process eroded and broke through a cinderblock wall during
their tests! Definitely out
of the range of the home shop, I decided!

Jon