Paul, what happened to the little prop dyno that you had mounted on
a trailer? I have been waiting for you to use it, to see what
changes if any you would recommend, before building one for
myself. Could you put Mark's engine on it? BTW, I have no need
for the trailer version. Mine could be solid mounted bolted down to
the shop floor. Jerry
The house project is eating all my spare time.
Extend the bottom legs further up under the engine
to balance it better. You don't need the static thrust
measuring capability as it can be misleading.
Rather than the bathroom scale there are other ways
of measuring the torque. A calibrated garage door
spring is one of them. Use a shock absorber to damp
out any oscillation.
Let me know if you need any advice.
Paul Lamar ...No rotor no motor.
I need LOTS of advice. Can I supply resistance without running a
prop? I have heard of driving a pump. Would it be belt driven off
the prop flange? Jerry
Do you have a 200 HP water pump? Takes a lot of v belts to
transfer 200 HP. Do you have a lake on the property?
Paul Lamar ...No rotor no motor.
Your question points out my ignorance and the size of the problem.
The simplicity of the prop version is what made me feel I could
install one inside the shop. (I have plenty of room.) What do
you suggest? The prop is dangerous, but could be caged, but the
prop wash would still be unacceptable inside the shop. It may be
that putting it on wheels avoids problems that a permanent
stationary set up would have. Jerry
Yes I think so. The trailers are about $200 from Harbor
Freight. Move the wheels back under the engine so it
does not take so much weight to balance it.
Here is a very early picture of Everett Hatch's prop dyno.
The flow straightening blades are not necessary.
Put the prop on backwards or use a pusher style prop.
Here is how to make a cheap dyno prop club. Use clear wood.
No knots. Straight grain. Leave it rough like this. No shaping or
sanding necessary. It is just going to beat up the air.
Make the boards about eight or ten inches wide.
Something around 50 inches long as a wild ass guess.
If you want more RPM cut the diameter.
You could also contact a prop maker and ask him if
he has any junk props he can sell you. Perhaps you
can cut off the damaged parts.
The trouble with the club it will give you
HP and BSFC at only one RPM.
You could make two or more at different diameters.
What would be best is a variable pitch hub.
Paul Lamar ...No rotor no motor.
The Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site.
http://www.rotaryeng.net
Copyright 1998-2006 All world wide rights reserved.
