Doug Fir vs: Sitka Spruce

Can anyone tell me the truth? When I read articles about the
difference between the two woods, the information says that fir is 23%
stronger than spruce. When I talk to people they say only 10%. Anyone
got a handle on this?
Lou

"Lou Parker" wrote in message
om...
Can anyone tell me the truth? When I read articles about the
difference between the two woods, the information says that fir is 23%
stronger than spruce. When I talk to people they say only 10%. Anyone
got a handle on this?
Lou

You need to download and read the publication in this link. It is the bible
of wood knowledge. The information you seek (and more) is there.
http://www.fpl.fs.fed.us/documnts/FP.../fplgtr113.htm
--
Jim in NC

!doctype html public "-//w3c//dtd html 4.0 transitional//en"
html
AMEN!!
pMorgans wrote:
blockquote TYPE=CITE"Lou Parker" wrote in message
bra ogle.com"news:61bea013.0310261924.4ac2d87a@postin g.google.com/a...
br Can anyone tell me the truth? When I read articles about the
br difference between the two woods, the information says that fir is
23%
br stronger than spruce. When I talk to people they say only 10%. Anyone
br got a handle on this?
br       &nb sp;      
Lou
pYou need to download and read the publication in this link.  It
is the bible
brof wood knowledge.  The information you seek (and more) is there.
bra href="http://www.fpl.fs.fed.us/documnts/FPLGTR/fplgtr113/fplgtr113.htm"http://www.fpl.fs.fed.us/documnts/FPLGTR/fplgtr113/fplgtr113.htm/a
br--
brJim in NC/blockquote
/html

Douglas Fir, Modulus of rupture 12.4ksi SpGr: .48
Sitka Spruce: Modulus of ruptu 10.2ksi SpGr: .36

Thus, Douglas Fir is about 22% stronger than Sitka Spruce, with about
4/3rds the density.

From The Wood Handbook, CH 4, Mechanical Properties
http://www.fpl.fs.fed.us/documnts/FP.../fplgtr113.htm

Lou Parker wrote:

Can anyone tell me the truth? When I read articles about the
difference between the two woods, the information says that fir is 23%
stronger than spruce. When I talk to people they say only 10%. Anyone
got a handle on this?
Lou

--
John Kimmel















In the desert
I saw a creature, naked, bestial,
Who, squatting upon the ground,
Held his heart in his hands,
And ate of it.
I said, "Is it good, friend?"
"It is bitter -- bitter", he answered,
"But I like it
Because it is bitter,
And because it is my heart."

On 26 Oct 2003 06:24 PM, Lou Parker posted the following:
Can anyone tell me the truth? When I read articles about the
difference between the two woods, the information says that fir is 23%
stronger than spruce. When I talk to people they say only 10%. Anyone
got a handle on this?

The difference between the two, is that sitka spruce will often forgive
less than perfect technique, while doug fir will split if you so much as
think the wrong thoughts about it. Sometimes even if you don't. Spruce,
on the other hand, is a joy to work with. A few years ago I turned some
unairworthy citabria spars into parts for a canoe. Still hoarding the
one leftover spar for future use. 8^)

----------------------------------------------------
Del Rawlins-
Remove _kills_spammers_ to reply via email.
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On 27 Oct 2003 06:30:14 GMT, Del Rawlins
wrote:

On 26 Oct 2003 06:24 PM, Lou Parker posted the following:
Can anyone tell me the truth? When I read articles about the
difference between the two woods, the information says that fir is 23%
stronger than spruce. When I talk to people they say only 10%. Anyone
got a handle on this?

The difference between the two, is that sitka spruce will often forgive
less than perfect technique, while doug fir will split if you so much as
think the wrong thoughts about it. Sometimes even if you don't. Spruce,
on the other hand, is a joy to work with. A few years ago I turned some
unairworthy citabria spars into parts for a canoe. Still hoarding the
one leftover spar for future use. 8^)

agree with del.
douglas fir will splinter along the arris while working it. pays to
wear gloves because of this. (ask dave king in canada about his corby
starlet experience)

had the dregs of a crashed corby starlet once. the main landing gear
beam is a composite of ash and spruce across the lower fuselage that
the two landing gear springs bolt to.
on the crashed aircraft douglas fir and ash had been used.
had no problems in use for about 5 years.
in the crash the part was shattered, much in the way that you would
split a block down with a tommahawk into kindling wood for starting a
fire.

in australia the jodel has been redesigned locally to use douglas fir
(oregon pine) in place of spruce and the examples I know of have no
serviceability problems due to the wood.

resorcinol formaldehyde glues it ok as will epoxy.
Stealth Pilot
Australia

Del Rawlins wrote in message ...
On 26 Oct 2003 06:24 PM, Lou Parker posted the following:
Can anyone tell me the truth? When I read articles about the
difference between the two woods, the information says that fir is 23%
stronger than spruce. When I talk to people they say only 10%. Anyone
got a handle on this?

The difference between the two, is that sitka spruce will often forgive
less than perfect technique, while doug fir will split if you so much as
think the wrong thoughts about it. Sometimes even if you don't. Spruce,
on the other hand, is a joy to work with. A few years ago I turned some
unairworthy citabria spars into parts for a canoe. Still hoarding the
one leftover spar for future use. 8^)

----------------------------------------------------
Del Rawlins-
Remove _kills_spammers_ to reply via email.
Unofficial Bearhawk FAQ website:
http://www.rawlinsbrothers.org/bhfaq/


Does that mean that after building my plane with fir instead of spruce
that I should be able to up my cruise speed, max speed and everything
else by 20%?
Lou

"
Does that mean that after building my plane with fir instead of spruce
that I should be able to up my cruise speed, max speed and everything
else by 20%?
Lou

No.

Scott

On 27 Oct 2003 03:23 AM, Lou Parker posted the following:

Does that mean that after building my plane with fir instead of spruce
that I should be able to up my cruise speed, max speed and everything
else by 20%?

Why settle for a mere 20% when you can go faster? Once you reach the
"normal" cruising speed, point the nose down, and then give a big yank.
Ought to pick up at least a few more knots that way.

----------------------------------------------------
Del Rawlins-
Remove _kills_spammers_ to reply via email.
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"Del Rawlins" wrote in
message ...
On 27 Oct 2003 03:23 AM, Lou Parker posted the following:

Does that mean that after building my plane with fir instead of
spruce
that I should be able to up my cruise speed, max speed and
everything
else by 20%?

Why settle for a mere 20% when you can go faster? Once you reach
the
"normal" cruising speed, point the nose down, and then give a big
yank.
Ought to pick up at least a few more knots that way.


One advantage of Douglas Fir here in Ireland is that it's got lot's
of knots to start with, you don't have to fly the thing to have at
least 100 knots.:-)
--

..
--
Cheers,
Jonathan Lowe
whatever at antispam dot net
No email address given because of spam.
Antispam trap in place


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Del Rawlins-
Remove _kills_spammers_ to reply via email.
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