SNIP

You are going to need ceramic bearings......

More than that. CAT 40 won't handle 32,000 rpm. Neither will ER.

No tapered-shank toolholder is reliable at those speeds. A key word
here is "reliable." If you really nurse it, you could get away with
it. Whether you need ceramic bearings depends on bearing diameter.
Again, it's a question of how well you can nurse the whole affair.

For around 15 years or so there has been extensive coverage of
spindles turning in this range of speeds. I kW is a small motor (why
CAT 40 with 1 kW?); it does present fewer problems than a 5- or 10hp
motor, which is where the action is these days in high-speed spindles.
As long ago as 2000, Fischer was making 100-hp spindles that would
turn 50,000 rpm, and 50-hp spindles that would turn 100,000.

There's plenty of discussion around about it. I'd start with
toolholding systems and work backwards.
The CAT 40 tool holder is stationary. The spindle fits inside it. I'm
pretty sure an ER11 or ER8 toolholder will work. According to the
bearing calculator I don't need ceramic bearings. I can see my post
wasn't clear. I will be making a spindle cartridge that fits into a
CAT 40 tool holder which will in turn fit into nthe machine spindle. I
hope my calculations are correct. I will be doing them over before
starting the build. Fortunately the motor doesn't need to spin at full
speed so I can test the spindle at lower speeds and work my way to
destruction . Maybe I should order 6 bearings instead of just three. I
will post my results.
Eric