Marc Wiese wrote:

The 1996 corvette GM 12v electric motor

driven air pump I have weighs just

2 lbs, 4 oz. I have no idea what amount of

air it will supply yet.

Paul Lamar teased:

Fill a balloon and weigh it before and after

:-)

Anybody care to do the math on the results?

Very funny Paul.  Without knowing the

"strength" of the balloon, or at least

the pressure of the air within, one cannot

determine the amount of air the

pump will supply.

BTW, since your considering this pump for

vacuum power instruments, wouldn't

it be better to measure the amount of air it

consumes (generating vacuum)

rather the amount of air is supplies?  :-)

Russell Kent
[See, I can be a smart aleck, too.]

Paul replied:

You are missing something Russell. Hint: What

does air weigh?

I ain't missing nothin'. How much air have you

got?  Hint: balloons fly because

they weight less than the surrounding air.

Russell Kent

Helium, hydrogen and hot air balloons fly. Others
just sit there.
The rubber is stretched until the air pressure
inside plus the rubber
tension equals the surrounding air pressure. The
balloon also
has a displacement just like a boat in water. This
reduces its
apparent weight and must be accounted for.

As I said it is easier to hook the pump to the gyro.

Paul Lamar

I understand there is a pusher in Fla. with a 13b

that uses a combination alternator, vacuum pump off of
a  chevette diesel engine (izusu?) I haven't checked
into it yet, but it might be a good way to reduce
weight.   Comments?  Jim Coffman

That sounds like Greg Richter's Cozy according to Chrissi it failed.
At OSH he had a aircraft vacuum pump on there and that failed on
the way up.

Paul Lamar
 
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