On Mon, 12 Sep 2005 17:30:23 -0500, Don Foreman
wrote:

On Mon, 12 Sep 2005 14:59:35 -0700, Grant Erwin
wrote:

Gunner Asch wrote:


I had a brand new Marathon Elect 10hp 3450rpm motor kicking around so
I decided to breadboard it up into a bigger RPC and see if it would
run the Airco. Getting it up to speed was the problem, as I couldnt
spin it fast enough with a rope wrapped around the shaft, so micky
moused up a 1/2hp 110vt 3450 moter, pulley and flat belt to spin the
big motors shaft directly, before applying single phase power to it.
Which worked just fine.

God that big 10hp motor is loud when it runs....I could hear it 200
yrs away, Of course..bolting it to a pair of I beams, then sitting
loose on the top of my welding bench turned the bench into a sounding
board....aaaaack!!

I bet if you worked on it you could get that idler to run a lot quieter. Make
the feet *right* so nothing is twisted, nothing is loose, everything's just
solid and no teeny warps. Then rubber-mount the whole bidness. I bet that would
knock off at least 15 dB right there. A little enclosure would help a lot too.

GWE
I think you could isolate vibration OK, but a 3450 RPM fan makes a
hell of a racket that would be more of a challenge. It could be done
with an acoustic enclosure, but I bet it'd be a lot easier
(especially for Gunner) to scrounge up a 1725 RPM motor.


Ayup..it really heavy on fan noise. The wind coming off the fan can be
felt at over 20 feet. It was so strong, I had to put up a wind shield
so it wouldnt keep blowing my sheilding gas away...10 feet away.

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner