Re: ( was Software ) now Servo Wars

> Now, at the risk of starting a flame war, I know many people brag or

insist

> that you need to have super high rapid speeds, but lets put this in
> perspective. IF you are operating a "manual" mill, how fast are the

rapids

> - 200 IPM? I doubt it as you would have to crank that handle real

fast. The

> point being is, if you can tolerate "slow" speeds, even a rather small
> servo can be geared to handle the forces necessary. This way, you

can get

> started with the small servos and later (with out "buying another

wife")

> and later replace the existing units with larger ones depending on your
> power supply.
>

As I have witnessed, many people laugh at slow rapids, others at huge
motors.

I think a fair rapid is twice the maximum required cutting speed.

If you will be cutting 1/8 alumiunm with a 1/4 inch four flute milling
cutter, you will be flying around the table.

if you are hogging out stainless with a 3/4 mill, your speeds will be
much slower.

The balance to that is the cost of your time.

If you have a job shop where income is involved, forget cheap, forget
surplus, forget custom, get the correct size mortgage the shop.

A too small motor that stalls on a part is useless.
a broken motor that takes a week to replace is useless.

Considder the number of rapids in a day. if you move the table from
end to end 10 times a day. 36 inches x10 = 360 inches and you move
100 ipm or 360 ipm, you can save 2 minutes a day, 10 minutes a week
and 500 minutes a year. at $10 and hour, that 500 minutes is 8 hours
or about $80.00 $50/hr=$400)

If you move that 100 times a day, that is $800 ($50hr=$4,000) and the
savings is more than the differental cost of a big motor.

A home-hobbiest can afford to take 5 cuts where a large motor would
allow 2.

Dave