wood species question

RST Engineering wrote:

Don't DO that at this hour of the morning. I HATE iced tea coming out my
nose.

{;-)


Better than hot coffee! :-)

Matt

"Lou" wrote
How long have you two been married?

Ouch! g
--
Jim in NC

"Gordon Arnaut" wrote in message
...
Moron,


You have not refuted one single thingI have said.

I have asked you how tho other wood strength properties, like tension come
in to play. You only tote one number; rupture. If you can't see that I
object to that, tough.


And then there are your comments about how you tried to be "nice?" When
was
that?

I was nice on my second reply, after you jumped me for calling your post
crap.

The reason you are atacking me is that you have
an old axe to grind. I remember you from the Ragwing list where you
launched
a similar attack on me out of the blue because I provided some good
information about a very serious structural issue with wing spars.


Now you have shown your true colors. You are paranoid. I have NEVER,
repeat, NEVER been on a ragwings list. I never have seen your name, before
the last few days.


When you saw me here, you launched a vicious attack like some crazed
pitbull. that's the reason for your sociopathic display here, not some
concern about people's safety. What a piece of work you are.

Wrong. Explain to me, and everyone else, how modulus of elasticity,
buckling, and stength related to tension of a wood sample comes into play.
Until you can do that, you have no buisness giving structural advise.

Bottom line is you know absolutely nothing about the subject under
discussion, as you have amply proved.


Either pick up the gauntlet or shut your
stupid obnoxious trap.

Oh, that's mature. who is the attacker now?

OK, I'll play 5th grade for you.

Make me shut up.

That's really the end of the story right there. Until you can actually
point
to factual errors on my part, your mindless braying is just noise.
Annoying
irritating, mindless noise.

I already have pointed out factual errors of ommision. Use all of the wood
strength properties. Do you think someone sat down and measured all of
those numbers just for the fun of it? Once again, they *are* important.

Go bark somewhere else, mouth-foamer.

Oh, you as such a master.

I give up.

Others, beware. Make the call yourself.
--
Jim in NC

"RST Engineering" wrote in message
...
We call each other a lot of names in these groups, and sometimes it gets
mean and sometimes it is just fun to watch the fur fly.

This is one step over the line.

*plonk*


Jim

I agree. I am 100% done with this one.
--
Jim in NC

Morgans wrote:
"RST Engineering" wrote in message
...

We call each other a lot of names in these groups, and sometimes it gets
mean and sometimes it is just fun to watch the fur fly.

This is one step over the line.

*plonk*


Jim


I agree. I am 100% done with this one.

Don't give up yet, I want to see how he responds to your telling him you
have never been on a "ragwing" list. :-)

Mouth-Foamer,

It could be that you were not on the Ragwing list. I don't keep track of
every little heel-nipper who comes yipping at me on these lists.

If that's the case, then you are really even more of a sociopath than I
assumed. To just come out of the blue and attack a person in the aggressive
and obnoxious way that you did, points to a serious personality disorder.

Also you know nothing about structures and yet you launch criticisms in a
shrill tone that would make people you do know what you are talking about.

Even the way you answer my posts tells me what an intellectual dwarf you
are. You snip my posting into little bites and insert meaningless little
one-sentence retorts in between. What's the matter, can't you compose your
thoughts into a coherent whole and put that down on paper?

Let me just recap for a moment because your snipping and inserting has
thrown the whole thread of this argument out of context. (Which is probably
what you want, because you realize that the only way you are going to get
out of this without being exposed as a complete jackass is to sow
confusion -- put up a smokescreen of meaningless verbiatge and then bug out
while people are scratching their heads trying to make sense of your
gibberish).

But let's summarize this thread very quickly so people don't lose sight of
what's under discussion.

In the contect of a discussion with Matt, I pointed out that it is not much
work to recalculate the size of structural wooden members in order to
substutute one of the wood species that is approved in AC-43.13b.

As an example I worked through substuting white pine for sitka spruce in a
Baby Ace spar, and arrived at a thickness dimension of 7/8" for pine as a
suitable substitute for 3/4" sitka.

I also noted that I prefer this to having boards shipped, because the boards
could be damaged in transit, and if the damage was compression failure it
would be very hard to detect, yet could be catastrophic in terms of the
structural integrity of the member.

Then a wild-eyed moron jumped in with all kinds of baseless accusations
about my the veracity of my information, peppered with unprovoked personal
insults.

This crazy nut then claimed how it would be impossible for compression
failure to happen in shipment unless there was a 10,000 pound box sitting on
top of the wood. He also added that this kind of force would blow the tires
and break the axles of the truck before it damaged the wood. This is very
accurate paraphrasing, but the actual quotes are there for all to see.

After first deciding to ignore this annoying idiot who obviously knows
nothing, I decided to set the record straight when I saw that some people
were still interested in the topic and were actually responding to this nut
in a serious way.

I pointed out how compression failure does not require huge amounts of
weight -- especially in small dimension lumber -- and can happen easily with
simple bending. I gave an intuitive eexample of bending a yardstick. I also
pointed out how easy it would be for a package of sitka sticks, which are
shipped in cardboard tubes, to be bent to a point where they don't actually
break or leave visible damage, but could have sustained compression failure
of fibers where they were bent.

The wild-eyed idiot then responded by backtracking from his obvious boo-boo
by trying to rewrite history and saying he had never said it would take a
10,000 pound weight sitting on top of the wood, but only 10,000 pounds of
bending moment.

So we see the socipathic tendencies coming out clearly as he tries to submit
an obvious lie in full view of everyone.

I will document this very precisely here, just so Mr. Personality Disorder
can see his pathology clearly at work:

Exhibit 1:

18/07/2005 4:56 PM, Idiot writes: "You HAVE to be totally kidding. Unless
that wood was sitting under a 10,000
lbs box on the UPS truck, it WILL NOT get compressive failure like that."

Exhibit 2: 19/07/2005 1:30 AM Idiot writes: (The first part is the snip he
used from my previous message).

" Idiot's comments about needing 10,000 pounds on top of the wood simply
illustrate to everyone what a loudmouth know-nothing he is.

"I was talking about a bending force, or can't you read?"


So Idiot, were you talking about a bending force when you said that you
would need a 10,000 pound box sitting on top of the wood? Or did that come
later when you realized your mouth flew off before your brain had a chance
to catch up? Please tell us because this looks like a very obvious and
embarassing flip-flop.

The bottom line is that this clown is trying to discredit the information I
presented, yet he has not been able to point to one single fault with my
calculations. But he is trying to make up for that by screaming very loud.

And now he's saying that I made errors of omission by not talking about
Young's modulus (also known as modulus of elasticity), or strenght in
compression or tension.

This is quite funny because just by parsing his criticisms it is obvious
that he understands nothing about structures, or where and how those
concepts fit in.

If there are any engineers here, maybe you can enlighten Idiot as to the
basics. Bending moments, shear and torsion are more complex stresses than
pure tension and compression (which Idiot is bleating about as being really
important).

In working out my calculation on resizing the wing spar, I addressed bending
moment, in order to show that this is not a difficult calculation. Pure
compression and pure tension are much simpler calculations -- all you have
to do is plug in the figures from the Forest Products Laboratory.

As a matter of proper engineering you would want to do all the calculations,
but as a practical matter in a wooden airframe, bending moment is the most
critical issue, because it is the biggest force acting on the airplane --
especially the wings.

The spars are the single most critical structure in the airplane. You can
rest assured that if bending moment of the spars has been properly
addressed, then pure tension and compression will likewise be suitably
addressed by applying the same dimension increase to members that are under
pure tension or compression.

Another issue that Idiot is bleating about is modulus of elasticity (E),
also known as Young's modulus. Yet just by looking at FPL tables we see that
pine is very similar to spruce and fir, and most other coniferous species in
E. In any case, stiffness is not a major concern. A structural member will
not fail because it lacks stiffness. It will only fail if it is not strong
enough.

In any case, pine and other species are specifically approved as substitutes
for certified aircraft by AC-43-13b.

Now, I think I have been very reasonable here and I think any people here
knowledgable about structures will agree that all of what I have said is
completely factual and true, and that nothing relevant to the discussion has
been left out. So what exactly is Idiot challenging? (Except me personally?)

This stupid ass continues to hurl abuse and unfounded criticisms. I could
dissect his nonsense sentence by sentence and really point up all of his
factual mistakes, but why bother. I think all the knolwedgable people here
can now plainly see that he doesn't know even the most fundamental basics.

Now I ask you, is it proper for a person who knows nothing about the subject
to make so much noise? Is he not simply creating an obstruction to
intelligent discourse?

I will just leave on a more amusing note. I see that in one of his earlier
posts, he said "I hate being like this." (Direct quote).

Yes, I can see how he hates suffering from a personality disorder that
compels him to behave inappropriately and then causes acute embarassment.
Still, I would caution that self-hating tendencies are a very serious matter
and I would strongly counsel seeking professional help.

Regards,

Gordon.


"Morgans" wrote in message
...

"Gordon Arnaut" wrote in message
...
Moron,


You have not refuted one single thingI have said.

I have asked you how tho other wood strength properties, like tension come
in to play. You only tote one number; rupture. If you can't see that I
object to that, tough.


And then there are your comments about how you tried to be "nice?" When
was
that?

I was nice on my second reply, after you jumped me for calling your post
crap.

The reason you are atacking me is that you have
an old axe to grind. I remember you from the Ragwing list where you
launched
a similar attack on me out of the blue because I provided some good
information about a very serious structural issue with wing spars.


Now you have shown your true colors. You are paranoid. I have NEVER,
repeat, NEVER been on a ragwings list. I never have seen your name,
before
the last few days.


When you saw me here, you launched a vicious attack like some crazed
pitbull. that's the reason for your sociopathic display here, not some
concern about people's safety. What a piece of work you are.

Wrong. Explain to me, and everyone else, how modulus of elasticity,
buckling, and stength related to tension of a wood sample comes into play.
Until you can do that, you have no buisness giving structural advise.

Bottom line is you know absolutely nothing about the subject under
discussion, as you have amply proved.


Either pick up the gauntlet or shut your
stupid obnoxious trap.

Oh, that's mature. who is the attacker now?

OK, I'll play 5th grade for you.

Make me shut up.

That's really the end of the story right there. Until you can actually
point
to factual errors on my part, your mindless braying is just noise.
Annoying
irritating, mindless noise.

I already have pointed out factual errors of ommision. Use all of the
wood
strength properties. Do you think someone sat down and measured all of
those numbers just for the fun of it? Once again, they *are* important.

Go bark somewhere else, mouth-foamer.

Oh, you as such a master.

I give up.

Others, beware. Make the call yourself.
--
Jim in NC

Just a small self-correction for the pedants out there who would gleefully
jump on anything that isn't crystal-clear.

I said that a structure will not fail because it lacks stiffness, but only
if it lacks strength. To be more precise, I'm talking here about bending
stress, not other types of stress, such as column buckling, where stiffness
does indeed come into play (see Euler's formula).

However when we are talking about airplanes, column buckling is only
relevant to the wing struts and these are not made of wood, but tubular
metal.

And just to address Mouth-Foamer's yipping about pure compression and
tension, maybe he can start by telling me which parts of the airplane are
under pure tension or compression?

Ha ha...I think I'll be waiting a good long time for that one.

What a pathetic moron.

Regards,

Gordon.






"Gordon Arnaut" wrote in message
...
Mouth-Foamer,

It could be that you were not on the Ragwing list. I don't keep track of
every little heel-nipper who comes yipping at me on these lists.

If that's the case, then you are really even more of a sociopath than I
assumed. To just come out of the blue and attack a person in the
aggressive and obnoxious way that you did, points to a serious personality
disorder.

Also you know nothing about structures and yet you launch criticisms in a
shrill tone that would make people you do know what you are talking about.

Even the way you answer my posts tells me what an intellectual dwarf you
are. You snip my posting into little bites and insert meaningless little
one-sentence retorts in between. What's the matter, can't you compose your
thoughts into a coherent whole and put that down on paper?

Let me just recap for a moment because your snipping and inserting has
thrown the whole thread of this argument out of context. (Which is
probably what you want, because you realize that the only way you are
going to get out of this without being exposed as a complete jackass is to
sow confusion -- put up a smokescreen of meaningless verbiatge and then
bug out while people are scratching their heads trying to make sense of
your gibberish).

But let's summarize this thread very quickly so people don't lose sight of
what's under discussion.

In the contect of a discussion with Matt, I pointed out that it is not
much work to recalculate the size of structural wooden members in order to
substutute one of the wood species that is approved in AC-43.13b.

As an example I worked through substuting white pine for sitka spruce in a
Baby Ace spar, and arrived at a thickness dimension of 7/8" for pine as a
suitable substitute for 3/4" sitka.

I also noted that I prefer this to having boards shipped, because the
boards could be damaged in transit, and if the damage was compression
failure it would be very hard to detect, yet could be catastrophic in
terms of the structural integrity of the member.

Then a wild-eyed moron jumped in with all kinds of baseless accusations
about my the veracity of my information, peppered with unprovoked personal
insults.

This crazy nut then claimed how it would be impossible for compression
failure to happen in shipment unless there was a 10,000 pound box sitting
on top of the wood. He also added that this kind of force would blow the
tires and break the axles of the truck before it damaged the wood. This is
very accurate paraphrasing, but the actual quotes are there for all to
see.

After first deciding to ignore this annoying idiot who obviously knows
nothing, I decided to set the record straight when I saw that some people
were still interested in the topic and were actually responding to this
nut in a serious way.

I pointed out how compression failure does not require huge amounts of
weight -- especially in small dimension lumber -- and can happen easily
with simple bending. I gave an intuitive eexample of bending a yardstick.
I also pointed out how easy it would be for a package of sitka sticks,
which are shipped in cardboard tubes, to be bent to a point where they
don't actually break or leave visible damage, but could have sustained
compression failure of fibers where they were bent.

The wild-eyed idiot then responded by backtracking from his obvious
boo-boo by trying to rewrite history and saying he had never said it would
take a 10,000 pound weight sitting on top of the wood, but only 10,000
pounds of bending moment.

So we see the socipathic tendencies coming out clearly as he tries to
submit an obvious lie in full view of everyone.

I will document this very precisely here, just so Mr. Personality Disorder
can see his pathology clearly at work:

Exhibit 1:

18/07/2005 4:56 PM, Idiot writes: "You HAVE to be totally kidding. Unless
that wood was sitting under a 10,000
lbs box on the UPS truck, it WILL NOT get compressive failure like that."

Exhibit 2: 19/07/2005 1:30 AM Idiot writes: (The first part is the snip he
used from my previous message).

" Idiot's comments about needing 10,000 pounds on top of the wood simply

illustrate to everyone what a loudmouth know-nothing he is.

"I was talking about a bending force, or can't you read?"


So Idiot, were you talking about a bending force when you said that you
would need a 10,000 pound box sitting on top of the wood? Or did that come
later when you realized your mouth flew off before your brain had a chance
to catch up? Please tell us because this looks like a very obvious and
embarassing flip-flop.

The bottom line is that this clown is trying to discredit the information
I presented, yet he has not been able to point to one single fault with my
calculations. But he is trying to make up for that by screaming very loud.

And now he's saying that I made errors of omission by not talking about
Young's modulus (also known as modulus of elasticity), or strenght in
compression or tension.

This is quite funny because just by parsing his criticisms it is obvious
that he understands nothing about structures, or where and how those
concepts fit in.

If there are any engineers here, maybe you can enlighten Idiot as to the
basics. Bending moments, shear and torsion are more complex stresses than
pure tension and compression (which Idiot is bleating about as being
really important).

In working out my calculation on resizing the wing spar, I addressed
bending moment, in order to show that this is not a difficult calculation.
Pure compression and pure tension are much simpler calculations -- all you
have to do is plug in the figures from the Forest Products Laboratory.

As a matter of proper engineering you would want to do all the
calculations, but as a practical matter in a wooden airframe, bending
moment is the most critical issue, because it is the biggest force acting
on the airplane -- especially the wings.

The spars are the single most critical structure in the airplane. You can
rest assured that if bending moment of the spars has been properly
addressed, then pure tension and compression will likewise be suitably
addressed by applying the same dimension increase to members that are
under pure tension or compression.

Another issue that Idiot is bleating about is modulus of elasticity (E),
also known as Young's modulus. Yet just by looking at FPL tables we see
that pine is very similar to spruce and fir, and most other coniferous
species in E. In any case, stiffness is not a major concern. A structural
member will not fail because it lacks stiffness. It will only fail if it
is not strong enough.

In any case, pine and other species are specifically approved as
substitutes for certified aircraft by AC-43-13b.

Now, I think I have been very reasonable here and I think any people here
knowledgable about structures will agree that all of what I have said is
completely factual and true, and that nothing relevant to the discussion
has been left out. So what exactly is Idiot challenging? (Except me
personally?)

This stupid ass continues to hurl abuse and unfounded criticisms. I could
dissect his nonsense sentence by sentence and really point up all of his
factual mistakes, but why bother. I think all the knolwedgable people here
can now plainly see that he doesn't know even the most fundamental basics.

Now I ask you, is it proper for a person who knows nothing about the
subject to make so much noise? Is he not simply creating an obstruction to
intelligent discourse?

I will just leave on a more amusing note. I see that in one of his earlier
posts, he said "I hate being like this." (Direct quote).

Yes, I can see how he hates suffering from a personality disorder that
compels him to behave inappropriately and then causes acute embarassment.
Still, I would caution that self-hating tendencies are a very serious
matter and I would strongly counsel seeking professional help.

Regards,

Gordon.


"Morgans" wrote in message
...

"Gordon Arnaut" wrote in message
...
Moron,


You have not refuted one single thingI have said.

I have asked you how tho other wood strength properties, like tension
come
in to play. You only tote one number; rupture. If you can't see that I
object to that, tough.


And then there are your comments about how you tried to be "nice?" When
was
that?

I was nice on my second reply, after you jumped me for calling your post
crap.

The reason you are atacking me is that you have
an old axe to grind. I remember you from the Ragwing list where you
launched
a similar attack on me out of the blue because I provided some good
information about a very serious structural issue with wing spars.


Now you have shown your true colors. You are paranoid. I have NEVER,
repeat, NEVER been on a ragwings list. I never have seen your name,
before
the last few days.


When you saw me here, you launched a vicious attack like some crazed
pitbull. that's the reason for your sociopathic display here, not some
concern about people's safety. What a piece of work you are.

Wrong. Explain to me, and everyone else, how modulus of elasticity,
buckling, and stength related to tension of a wood sample comes into
play.
Until you can do that, you have no buisness giving structural advise.

Bottom line is you know absolutely nothing about the subject under
discussion, as you have amply proved.


Either pick up the gauntlet or shut your
stupid obnoxious trap.

Oh, that's mature. who is the attacker now?

OK, I'll play 5th grade for you.

Make me shut up.

That's really the end of the story right there. Until you can actually
point
to factual errors on my part, your mindless braying is just noise.
Annoying
irritating, mindless noise.

I already have pointed out factual errors of ommision. Use all of the
wood
strength properties. Do you think someone sat down and measured all of
those numbers just for the fun of it? Once again, they *are* important.

Go bark somewhere else, mouth-foamer.

Oh, you as such a master.

I give up.

Others, beware. Make the call yourself.
--
Jim in NC

I'm taking up a collection in Oshkosh. It is obvious that there is a person
on this ng that can't afford their meds. We owe it to him as a colleague.


Jim

Ha, ha, ha...another chestnut from the avionics Hemingway of Kitplanes.

Regards,

Gordon.

PS: For anyone out there that might still be interested in serious
discussion of wood, I want to just add a little about compressive strength
and tensile strength as it relates to wood species substitution.

Using the same FPL data I used earlier, we see that spruce has a maximum
crushing strenght of 5,650 psi, while pine is 4840 psi, which makes pine
exactly 85 percent as strong in compression. This is nearly the same
difference as in bending -- and as I noted earlier, most of the other
measures will be similarly in line.

But just to see if my statement that 7/8' pine will adequately substitute
for 3/4 spruce, let's calculate. Since stress is force per area, we can see
that a 3/4" spruce member will be able to withstand a maximum compressive
stress of 0.75(squared) x 5650 = 3178 psi.

How big would our pine member have to be? Well by rearranging the formula
3178 divided by 4840 will give us the dimension squared, which is 0.81 inch,
again somewhat less than 7/8".

So just as in the bending moment calculation we see that substituting 7/8'
pine for 3/4" spruce gives us a member that is actually a little bit
stronger. It is also a tiny bit heavier, but this is negligible.

However I should point out that going through the exercise we just did is
not proper methodology. I am only doing it to prove a point.

The proper method is to first identify the structural member we are
interested in analyzing, like I did with the wing spar. Next we have to know
how much load this member is expected to carry. Only then does it make sense
to determine the size of the member.

But like I said, let's see if Mouth-Foamer can tell us which pieces of the
plane are under pure compression or tension. (Since he is so concerned aobut
that and is basing his whole character assassination on me on that stupid
notion).

In the meantime, I hope Mr. Personality is getting the couch-time he so
desperately needs. And I hope he doesn't forget to remind his analyst,
"first do no harm."







"RST Engineering" wrote in message
...
I'm taking up a collection in Oshkosh. It is obvious that there is a
person on this ng that can't afford their meds. We owe it to him as a
colleague.


Jim

"RST Engineering" wrote in message
...
I'm taking up a collection in Oshkosh. It is obvious that there is a
person on this ng that can't afford their meds. We owe it to him as a
colleague.

I've got a bunch of old meds I can bring. You're right, Jim. He's pitiful.
And plonked.

Rich S.