Re: High Speed Spindle for SIEG X2 - Finally .... ... just a nagging doubt ?

Message #88701
"Chris Horne" <chris@...> wrote:

> A bit of a question regarding these proxxons. I like the Proxxon

tools a lot for hand use and this new one looks just the biz..
but. The literature says 'rated for 30 minutes continuous'. I don't
want to spoil the party, but. Has anyone used them as a mill
spindle for an extended period of time? My application is 15
minutes on, 30 seconds off all day long.. is it going to go bye
byes in short order? and if it is the bearings that fail.. can
they be changed relatively easily?

> Chris

Chris, I think that KDN Tool may have done some testing which
demonstrated a longer continuous duty cycle. The only way to get a
continuous duty cycle is $2,000 NSK Astro-E 250. What I plan to do
is run the thing and observe the temperature rise. It has self
adjusting motor bearing pre load adjustment. It's a cute solution -
but what do you expect for $110. Changing bearings - I don't think
so.

What I plan to do is purchase a second unit and switch units during
long run lengths. At $110 why not. It switches in a few seconds.
What I need to find out is - does DeskCNC have a time out feature
where I can specify a length of time to run, and then soft stop and
park, so that I can exchange spindles, turn it back on and continue
the machining. Some of the machining sculpting / engraving could
take 12 hours for one job. But I think that the Proxxon IB/E will
run for hours on light chip loads, and small depths of cut. It will
probably hog out aluminum for a few minutes on a short job. It all
has to do with i squared r. High power, high current, rising
temperature. Take a look at the cutting torque and power equations
I posted. If your application will require more than 100 watts
continuous then its going to heat up

As far as the "30 minutes" duty cycle, drop KDN Tool an e-mil and
ask them.

God bless you.

Bill Perun