On Sat, 02 Oct 2010 23:37:49 -0400, John
wrote:

Ignoramus6607 wrote:
Someone is offering me a lot of appx. 300 lbs of used HSS endmills,
which are neatly sorted by size and need resharpening, for $75.

Let's say that I had an end mill sharpener like a Darex V90 or
whatever. Realistically, how long does it take to resharpen an end
mill (I would hire someone) and how much can I get per dozen of
"professionally" sharpened end mills, say in 1/4" size.

i


For the hobbyist they may have a value but a commercial shop would
probably have no use for them because of them being undersized from the
sharpening. Unless you can hold the size to within a tenth or two you
must reprogram the cutter comp for each end mill as compared to using
new end mills that are right on size.

The small 1/4 in end mills are not worth that much. Larger ones over
3/4 inch start to become economical to sharpen because of the higher
replacement cost.


John

Maybe I'm just a little bit weird, but I actually LIKE when an endmill
is just a little undersize....

.....as an example, if I am using a 3/8" endmill and the print is
actually calling for a 3/16" corner radius, if I just use the 3/8", I
may end up with chatter in the corner....

....but if I use a resharpened 3/8....it'll likely be around .360" and
all I need to do is change the tool diameter in the tool setup and I'm
done.

That gives me the strength and chip load of a 3/8 while being
undersize just enough to generate the radius rather than forming it.

And yes, I'm talking about in a commercial setting.

The only real drawback to it is that if there was any coating...TiN,
TiAlN, whathaveyou...it's largely ineffective.

Luck

Mike