Weight saving exercise.

To save weight, if an alu prop weight 30 lb. a birch will be 7 lb., mahogany
5.5 lb.

for efficiency, use the aluminium!

Jan Carlsson
www.jcpropellerdesign.com


use a wood or composite prop not aluminum

I went to your site. Why not aluminum?


for the rest of the body, use meat, fat, egg, fish, vegetable, fruit.
stay out of rice, potatoes, pasta, bread (Atkinson method)


Good Friday ....McDonald's $1.00 fish sandwich ...w/cheese


Montblack - raised Catholic

To save weight, if an alu prop weight 30 lb. a birch will be 7 lb.,
mahogany
5.5 lb.

for efficiency, use the aluminium!

Jan Carlsson
www.jcpropellerdesign.com


Aluminum will weigh 5 x the mahogany? Wow.

At 100-110 mph how much (WAG) efficiency would the wooden prop lose, on say
an Ercoupe?

What's the cost difference between aluminum and wooden props?

Why do people buy birch instead of mahogany?

Cool, a prop person g


Montblack

"Montblack" wrote in message
...

Aluminum will weigh 5 x the mahogany? Wow.

Specific gravity of Aluminum = 2.7
Specific gravity of Mahogany = ~.5

What's the cost difference between aluminum and wooden props?

New Ed Sterba Birch prop ~ $600. New Sensenich Aluminum $2,000. These are
rough figures.

Why do people buy birch instead of mahogany?

Birch has a specific gravity ~ .7 and is a lot stronger per pound than
Mahogany when used for a prop.

Rich S.

"Rich S."
:

"Montblack" wrote in message
...

Aluminum will weigh 5 x the mahogany? Wow.

Specific gravity of Aluminum = 2.7
Specific gravity of Mahogany = ~.5

What's the cost difference between aluminum and wooden props?

New Ed Sterba Birch prop ~ $600. New Sensenich Aluminum $2,000.
These are rough figures.

Why do people buy birch instead of mahogany?

Birch has a specific gravity ~ .7 and is a lot stronger per pound than
Mahogany when used for a prop.



Might go to a wood prop if the one I have doesn't work out. But it is quite
a good prop, and it's absolutely gorgeous, to boot!

"Montblack" wrote in message
...
To save weight, if an alu prop weight 30 lb. a birch will be 7 lb.,
mahogany
5.5 lb.

for efficiency, use the aluminium!

Jan Carlsson
www.jcpropellerdesign.com


Aluminum will weigh 5 x the mahogany? Wow.

At 100-110 mph how much (WAG) efficiency would the wooden prop lose, on
say an Ercoupe?

What's the cost difference between aluminum and wooden props?

Why do people buy birch instead of mahogany?

Cool, a prop person g


Montblack

The wood prop is probably 3 to 5 percent less efficient, especially in
climb.

A new sensenich wood prop is about $1500. A metal prop is twice that.

Birch is more readily available and stronger and cheaper. Aircraft mahogany
is real hard to come by any more. It has to be real mahogany, not "luan" or
some other tropical wood that looks sort of like mahogany.

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )

"Jan Carlsson"
:

To save weight, if an alu prop weight 30 lb. a birch will be 7 lb.,
mahogany 5.5 lb.

for efficiency, use the aluminium!


Well, in this case the prop would be very efecient indeed. It's a 76 inch
ground adjustable Ham Standard with a very nice section. That menas, of
course, that I can screw around with the pitch to get the perforamnce I
need.

Wood or Metal is also a q of balance, if the plane tend to be tail heavy a
metal prop is better then adding weight, or the other way if...

The hollow steel prop that is/was on Stearman was/is noticeable more
efficient then the common replacement Sensenich wood.

Beach, Ash or Beech is very strong to weight, a mahogany with a lot of clear
coats is a perfect thing to make the other plane owners being jealous.

Jan Carlsson
www.jcpropellerdesign.com

"Fortunat1" skrev i meddelandet ...
"Jan Carlsson"
:

To save weight, if an alu prop weight 30 lb. a birch will be 7 lb.,
mahogany 5.5 lb.

for efficiency, use the aluminium!


Well, in this case the prop would be very efecient indeed. It's a 76 inch
ground adjustable Ham Standard with a very nice section. That menas, of
course, that I can screw around with the pitch to get the perforamnce I
need.

"Jan Carlsson"
:

Wood or Metal is also a q of balance, if the plane tend to be tail
heavy a metal prop is better then adding weight, or the other way
if...

The hollow steel prop that is/was on Stearman was/is noticeable more
efficient then the common replacement Sensenich wood.


Coincidentally, that's pretty much what I have, on a smaller scale.