I upped my spindle to 6K and rapids to 400 ipm about 3 years ago, and it works perfectly. As far as how, a very helpful gentlemen took the time to email me the step by step. Here is the text from that email:
First off, you really need to do both mods. Rapids are fabulous, but you
need the ability to turn carbide faster when necessary. These machines
don't make a lot of torque at high rpms, but they are great up to .5" cutter
diameter, so be prepared to learn to carve rather than hog. I do run at
6000 occasionally, but I frequently run between 4500 and 5500 with up to .5"
cutter on soft alloys and plastics. For the rpm mod, follow this
recipe...and remember to slowly let the machine ramp up over half a day or
so...bumping it up occasionally, before you run at higher rpms so that you
properly break in the bearings at that speed. The tm1-p is the same spindle
and runs at 6k, but there is the same break in process when it lands on your
floor. I usually start by hitting mdi, typing in 1000 and hitting spindle
cw button. Then every once in a while, increase spindle rpm by 10%.
Anyway, I have been running at these speeds for a few years with no problem,
so don't be afraid. Also, every day that you intend to let your spindle run
in the upper rpm's, remember to let the machine warm up properly and watch
your spindle load. Recipe for rpm is :
You first have to unlock the Parameters to do this.
1) Press Emergency stop
2) Press the SETNG/GRAPH key
3) Type 7 the push the down arrow
4) Use the Left or Right Arrow to change to off.
5) When off is shown press Write/Enter
Then follow these steps
1) Press Param/Dgnos
2) Enter 131
3) Press down Arrow
4) Change parameter 131 from 4000 to 6000 and press Writr/Enter
5) Enter 183
6) Press down arrow
7) Change parameter 183 from what it is to 20000, mine was 13333, and press
Write/Enter
Now that you know how to unlock and find parameters, this is the rapid mod :
Turn the parameter lock off and change the max speed for all three axis by
TWICE its current setting. The parameters are listed under 'X PARAM A', 'Y
PARAM A' and 'Z PARAM A'. The factory setting for each axis was 462394 which
equals 5.1 meters/minute. Change them to 924788 and that will equal 10.2
meters/minute. 10.2 meters times 39.37 inches/meter equals 401.574 inches
per minute. Piter also changed the acceleration two fold, and while that
might make the machine a little faster, my thoughts were that it would be an
unnecessary amount of extra force on the thrust bearings that wouldn't be
worth the extra second or two it saved per cycle. I left the acceleration at
3000000. This mod was extremely simple and to me just as important as the
max rpm mod. Just remember to back the rapid down when testing a new
program.....I generally use 25% when trying out a new one. You will LOVE
your new tool change speed. Feel free to ask anything else.