Re: [CAD_CAM_EDM_DRO] What kind of motor should I use?

In a message dated 03-Feb-02 12:27:51 Central Standard Time,
prototype@... writes:

> The only problem, other than noise, that I'm aware of is that the price on
> the #7518 just went up to $330 usd at discount. I paid $275.

You call this a "problem"??? Think about Perske 400 Hz. 3-phase
router-motors! The motor/collet alone is around $1000, and it is USELESS
without the motor-generator power-converter which gives you 400 Hz. 3-phase
power for the thing, and that will cost you another $3000 or so, and take up
about as much room as three 5 hp "tool motors" all in a row!

One would THINK they would design these totally-enclosed external-fan-cooled
24,000 RPM motors to be less noisy than the "universal" type motor which is
noisy for you. BUT! "That's someone else's job!" is the response, and you
get a fan in a SQUARE cast-iron duct-cover at the top of this motor, with a
fan-disk/impeller thing inside that, resulting in a near-SIREN of a
noise-maker! Makes the noise from the kind of motor YOU have seem like an
infant crying in another room, door closed!

Anyway... If you intend to use this CNC X-Y router-table thing more than a
total of 5 running-hours per week, expect to replace that router every couple
of months, if not weeks! They just aren't EXPECTED to last many
running-hours! But the HF 3-ph kind, cost notwithstanding, will run many
hours until bearings need replacing. NO brushes!

Lotsa luck! Jan Rowland


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