Doug Fir vs: Sitka Spruce

You cant increase your speed by 20%...but you CAN DECREASE your useful load
by about 12% (if I have my numbers right). Fir is a little heavier than
Spruce.
Dave...D as in "Duh"...A...V...E
"Lou Parker" wrote in message
om...
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

On Thu, 30 Oct 2003 17:17:15 -0500, "D Reid" wrote:

You cant increase your speed by 20%...but you CAN DECREASE your useful load
by about 12% (if I have my numbers right). Fir is a little heavier than
Spruce.

I just finished a new battery box for my Fly Baby. Actually TWO battery
boxes, after the first one (made of oak) got laughed out of my EAA chapter.

(Hey, I do a bit of non-aviation carpentry. I *love* working with oak!)

FWIW, the poplar one weighed 1.25 pounds. The nearly-identical oak one
weighed a half-pound more... a 40% weight penalty.

Ron Wanttaja

You cant increase your speed by 20%...but you CAN DECREASE your useful load
by about 12% (if I have my numbers right). Fir is a little heavier than
Spruce.

I just finished a new battery box for my Fly Baby. Actually TWO battery
boxes, after the first one (made of oak) got laughed out of my EAA chapter.

(Hey, I do a bit of non-aviation carpentry. I *love* working with oak!)

FWIW, the poplar one weighed 1.25 pounds. The nearly-identical oak one
weighed a half-pound more... a 40% weight penalty.

Ron Wanttaja
++++++++++++++++++++++++++++++

SO?????

Won't your Fly Baby carry a half-pound?
If not, fly barefoot and save 300% or more. g


Barnyard BOb --
If flying is the most fun you can have with your clothes on...
How much fun can flying naked be?

I just finished a new battery box for my Fly Baby. Actually TWO battery
boxes, after the first one (made of oak) got laughed out of my EAA chapter.

(Hey, I do a bit of non-aviation carpentry. I *love* working with oak!)

FWIW, the poplar one weighed 1.25 pounds. The nearly-identical oak one
weighed a half-pound more... a 40% weight penalty.

I'd have thought you'd use spruce, it's even more poplar... :-)

Ed Wischmeyer

In article , Ron Wanttaja says...

I kinda like either Black Walnut or Balsa :-) But I also think the subtle hues
of Cherry can blend into a harmony of tones that are a feast to the senses....
I really liked the use of Oak tho' it was a nice touch.

Chuck S


I just finished a new battery box for my Fly Baby. Actually TWO battery
boxes, after the first one (made of oak) got laughed out of my EAA chapter.

(Hey, I do a bit of non-aviation carpentry. I *love* working with oak!)

FWIW, the poplar one weighed 1.25 pounds. The nearly-identical oak one
weighed a half-pound more... a 40% weight penalty.

Ron Wanttaja

(Lou Parker) wrote in message . com...
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 know that Douglas Fir is not fir. That may be the source
of the confusion here. Douglas Fir is also known as Oregon Pine and
it is not a pine either. Douglas Fir is its own genus, I forget the
Latin name but understand that it translates to 'pseudo-hemlock' and
no, it's not a hemlock either.

Softwood lumber is often classified in 'species groups' with minimum
standards for tensile strength for each group. The cheapest is usually
S-P-F which stands for spruce, pine or fir. Another category is
'Hem-Fir' which may be hemlock or (true) fir. Doug Fir is usually
either grouped by itself, or with Larch. Southern Yellow Pine also
is usually grouped by itself.

Fir, pine, spruce, and hemlock are genuses. THere are several species
within each genus and many will also hybridize in the wild. I think
there is only one species of Douglas Fir.

But there are also significant differences within Douglas Fir depending
on where it is grown and whether it is old growth or second growth.

If the wood you are buying or reading about is just called fir, it
probably is NOT Douglas Fir.

Hope this helps.

--

FF

Fred the Red Shirt wrote:
[ generally good description regarding how Doug fir is not a true fir and
other things ]

If the wood you are buying or reading about is just called fir, it
probably is NOT Douglas Fir.

I think this depends upon where you are buying it. Here in Oregon 80% or so
(warning: unsubstantiated number) of the evergreens are Doug fir. I think
its pretty safe that the "fir" at my local lumber yard is indeed Doug fir.

Now, it is also second growth Doug fir and is hardly suitable for a dog
house much less an airplane.

They just don't make trees like they used to.

--
Frank Stutzman
Bonanza N494B "Hula Girl"
Hood River, OR

Frank Stutzman wrote:
Fred the Red Shirt wrote:
[ generally good description regarding how Doug fir is not a true fir and
other things ]


If the wood you are buying or reading about is just called fir, it
probably is NOT Douglas Fir.


I think this depends upon where you are buying it. Here in Oregon 80% or so
(warning: unsubstantiated number) of the evergreens are Doug fir. I think
its pretty safe that the "fir" at my local lumber yard is indeed Doug fir.

Now, it is also second growth Doug fir and is hardly suitable for a dog
house much less an airplane.

They just don't make trees like they used to.


FYI only a small fraction of the wood in any store in oregon comes from
here. And Doug fir only makes up a small part of our forest, Hemlock,
Pine and various hardwoods make up the bigger part. MOst of whats sold
aaround the country as "fir" is actually Hemlock and a lot of it
comes from Canada...

There are small millworks in Oregon that will make sure you get
what you ewwant for a fairly small premium. Even Sitka Spruce
is available if you do some looking.

Dave
Oregon Native and Forest service brat.

D.W. Taylor wrote:

FYI only a small fraction of the wood in any store in oregon comes from
here.

I could be biased by my location. I don't buy wood in any metro area as I
don't live there. I am currently having a house built and everything that
has been delivered has had a stamp or tag on it that said either SDS (a mill
in Bingen WA, which is barely accross the Columbia) or Warm Springs (which I
assume means it comes from the Warm Springs Indians).

Now, on the other hand, I had a pole barn built last spring. It was a kit
and the outfit that put it togather was from Canby (greater Portland area).
Every stick of that building came from Canada. I was told it was "Canadian
Pine." It was good looking wood, too. Much tighter grain, less knots than
what I can get locally.

Oregon Native and Forest service brat.

Also an Oregon Native. I'm also the first of my family NOT to be making a
living in the timber industry. Put myself through college setting chokers
on some mighty big Douglas fir.

--
Frank Stutzman
Bonanza N494B "Hula Girl"
Hood River, OR

"D.W. Taylor" wrote in message ...
Frank Stutzman wrote:
Fred the Red Shirt wrote:
[ generally good description regarding how Doug fir is not a true fir and
other things ]


If the wood you are buying or reading about is just called fir, it
probably is NOT Douglas Fir.


I think this depends upon where you are buying it. Here in Oregon 80% or so
(warning: unsubstantiated number) of the evergreens are Doug fir. I think
its pretty safe that the "fir" at my local lumber yard is indeed Doug fir.

I was
remiss in not explaining more. There is an industry standards
organisation, the American Softwood Lumber Association that sets
standards for softwood lumber. They establish standards for species
groups, dimensions for standard lumber sizes etc.

There is a standard for Douglas Fir and a different standard for
Hem-Fir. A higher minimum strength is required for Doug Fir than
for Hem-Fir. If the lumber is just labeled 'Fir' and it really is
Doug fir then it is mislabeled as an inferior product. If it isn't
Doug Fir it almost certainly isn't as strong as Doug Fir.

Now, there is no requirement that anyone use the standards set by
the ASLA. Home Depot certainly does not. A friend in S.Cal had
a deck made with Doug Fir timbers. THere were paper tags with
bar codes on the lumber that said 'GRN FIR' (Green Fir) but the
inked stamp from the actual lumber company that milled the
lumber was the trademark triangle with 'DF' in it. IOW,
Home Depot was relabeling the lumber as an inferior product,
no doubt through ignorance or indifference.

I think Hem-Fir, S-P-F and few other designations are trademarked
by the ASLA, but a commonly used word or phrase cannot be a trademark
so 'Douglas Fir', or just 'Fir' cannot eb tardemarked and that's
why there are special symbols. I think there is a trade group
just for Douglas Fir, a Google search should turn them up.

So you may be right but you certainly shouldn't count on the
lumber having the properties of Douglas Fir unless it is clearly
waranteed as such.

....


FYI only a small fraction of the wood in any store in oregon comes from
here. And Doug fir only makes up a small part of our forest, Hemlock,
Pine and various hardwoods make up the bigger part. MOst of whats sold
aaround the country as "fir" is actually Hemlock and a lot of it
comes from Canada...

It ought to be labeled Hem-Fir. But maybe it isn't because the
supplier does not want to warantee that it meets the ASLA standard
for Hem-Fir. I've seen a lot of 'oak' furniture (without the
quotemarks around the oak) that is made from rubber wood. A fair
bit of 'maple' furniture is being made from beech these days and
it has often been a common practice to substitute ash for oak w
in places where the former is cheaper.


There are small millworks in Oregon that will make sure you get
what you ewwant for a fairly small premium. Even Sitka Spruce
is available if you do some looking.


Yep. The best (and cheapest) wood is bought direct from the
sawyer.

--

FF