"Bob La Londe" wrote in message
...
Ok... I really need a high speed spindle machine that is bigger, faster
and has better wear characteristics than the Taig. The Hurco is coming
along nicely, but it definitely does not have a high speed spindle. Not
even close. I've played with the idea of just using a router on it like I
did the Taig, but then its kind of a headache to deal with switching
spindles in control. No horrible, but not great. I have not found a
speed multiplier I can afford so I was thinking about making my own belt
drive spindle with pulley's to multiply speed, and then just mount it with
a router-esque style spindle mount on the quill of the Hurco. Yeah, it's
a lot of work, but with some planning I would not have to do any controler
changes when going from one spindle to the other. Just load a different
machine profile depending on which spindle I planned to use. This leaves
coolant spray. At 25K-35K RPM even a 1/32" cuter throws coolant
everywhere.

When you get up to that speed, you probably would be better off running dry.
High-speed milling is generally done dry these days, or with a very lean
mist of vegatable oil. VW uses peanut oil.

At those speeds, in commercial milling of steel or iron, cutters typically
are multi-coated. If the top coat or the second coat is aluminum oxide, as
it often is for cutters made for high-speed machining, using coolant will
wreck your cutters in a hurry.

I put the Taig in a full enclosure because of it, and it works pretty
good. Putting the Hurco in a full enclosure is problematic at best. If I
stick with 5000 RPM and slower machining with the stock spindle (not
suited for my most common jobs) I could use a fence on the table, like
Iggy and other have used on their knee mills, but it won't even come close
to containing the spray of a high speed spindle. Maybe some form of
accordion way covers that slide on rails inside the the top of the fence
pushed back and forth by the quill?

Alternatively, I could just use the Hurco to make gantry style router
machines. Well some of the parts. My concern then is (as the title of
this post says) is rigidity. Most gantry router machines are made out of
aluminum. Since I actually push a cutter hard enough to momentarily bog a
1HP router from time to time would they be rigid enough for the job? I
really don't have or plan to have the facilities to melt and pour cast
iron so my thoughts were could I get somewhere in between by making the
gantry routers out of C-channel steel. The Hurco could certainly do all
the cutting on it. My big concern is that I recall discussions here and
elsewhere about harmonics, etc in regards to why machine tools are
machined cast iron rather than steel.

No I can't really afford the step up to a "real" high speed machine yet.