Today's Message Index:
----------------------
1. 01:24 AM - Re: [Shaw Suspected Junk Email] Re: wood vs steel struts (Clif Dawson)
2. 01:27 AM - Re: Douwe's truck (Clif Dawson)
3. 04:00 AM - Re: Re: wood vs steel struts (helspersew@aol.com)
4. 04:54 AM - Re: Re: wood vs steel struts (Jack Phillips)
5. 05:54 AM - Re: Re: wood vs steel struts (Michael Orth)
6. 06:20 AM - Re: Latex Paint Forum (womenfly2)
7. 06:25 AM - Re: Re: Pietenpol Picnic (Charles Burkholder)
8. 06:31 AM - Re: Re: WW2 Jeep Gauges ()
9. 06:31 AM - Re: Still Learning to Fly (Charles Burkholder)
10. 06:46 AM - Re: WW2 Jeep Gauges (TriScout)
11. 06:47 AM - Re: Still Learning to Fly (John Francis)
12. 06:51 AM - Re: WW2 Jeep Gauges (TriScout)
13. 07:07 AM - Re: 4130 tubing FOR SALE (Trevor)
14. 07:24 AM - rudder & elevator hinges (Trevor)
15. 07:34 AM - Re: engine out.. (bender)
16. 07:36 AM - Re: wood vs steel struts (nightmare)
17. 02:15 PM - Re: Re: wood vs steel struts (John Woods)
18. 02:58 PM - Re: Re: wood vs steel struts (Jack Phillips)
19. 03:08 PM - ELT Location (Larry Morlock)
20. 03:54 PM - Re: wood vs steel struts (dgaldrich)
21. 04:12 PM - Re: ELT Location (Gary Boothe)
22. 04:42 PM - Re: Re: engine out.. (Gary Boothe)
23. 04:45 PM - Re: Re: Latex Paint Forum (gliderx5@comcast.net)
24. 05:13 PM - Re: engine out.. (curtdm(at)gmail.com)
25. 05:46 PM - My "hood ornament" (Douwe)
26. 06:00 PM - Re: Re: wood vs steel struts (Jack Phillips)
27. 06:14 PM - Re: My "hood ornament" (Gary Boothe)
28. 06:15 PM - Re: wood vs steel struts (nightmare)
29. 06:43 PM - Sunset - send in your favorite photo (Douwe)
30. 06:57 PM - Re: Re: wood vs steel struts (Jack Phillips)
31. 08:12 PM - Re: Sunset - send in your favorite photo (Greg Cardinal)
32. 09:41 PM - Re: wood vs steel struts (nightmare)
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Subject: | Re: wood vs steel struts |
Another, much lighter, possibility.
http://www.youtube.com/watch?v=DarTJsvbaQk
Hmmmm......maybe the entire enchelada, er,
airplane even. :-)
Clif
You may want to buy streamline aluminum struts and then wrap them with
a thin wood veneer.
Michael Perez
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Subject: | Re: Douwe's truck |
It wasn't singing was it? I'll bet it wasn't.
"Never try to teach a pig to sing. It wastes your time and it annoys the
pig. " Someone
Clif
> Douwe , I found your truck at the San Antonio airport
> Paul Donahue
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Subject: | Re: wood vs steel struts |
Paul,
I used four of the small Carlson struts. They work great. Larry Williams h
as them also. His Piet has many miles on it.
Dan Helsper
Puryear, TN
-----Original Message-----
From: nightmare <pauldonahuepilot@yahoo.com>
Sent: Sun, Jun 16, 2013 10:49 am
Subject: Pietenpol-List: Re: wood vs steel struts
om>
Great resource. Better price than I thought. I imagine the "small strut" i
s
acceptable.
--------
Paul Donahue
Started 8-3-12
do not archive
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402792#402792
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Subject: | Re: wood vs steel struts |
Fairly simple to calculate. First, figure out what gross weight your
airplane will have (in order to make this calculation conservative, pick
a
number higher than you really think it will be). For the purpose of
this
exercise, let's say the gross weight is 1300 lbs.
Then multiply that by the highest load factor (G-load) you would expect
to
survive in extreme turbulence or maneuvers. 5 G's is a common number
for
ultimate loading (the load that would cause something to break). So
this
means the wing is carrying 1300 x 5 or 6,500 lbs of load.
Most of the wing load is carried by the lift struts. A Pietenpol has a
29'
wingspan, with a 2' wide centersection, so each wing panel is 13' 6"
wide
and carries 13.5/29 or 47% of the load, which in this example is 3,025
lbs.
Since the lift struts attach in the middle of the wing panel, virtually
all
of the lift load is transferred to the struts, with very little load
carried
by the bolts attaching the wing panel to the centersection (low enough
to be
ignored in this example). So the two lift struts on each side carry
3,025
lbs between them.
Calculating how much of that load is carried by the front strut and how
much
by the rear is a bit more difficult. The distribution of load varies
with
the location of the center of pressure, which moves around as the angle
of
attack changes, and the location of the center of gravity, which varies
with
how the airplane is loaded (fuel and passengers, for example). It is
probably safe to say that the front strut carries up to about 3/4 of the
wing load, since it is pretty close to the C.G.
So that means with a 1300 lb Pietenpol loaded to 5 G's by turbulence or
extreme aerobatics, the front struts each are carrying (3/4)x(3,025) or
2,270 lbs.
OK, we've found the load the struts carry. The stress is simply that
load
divided by the cross sectional area of the strut. For a round tube, the
area is easy to calculate: Area = =F0(d2outside - d2inside)/4
Assuming you are using 1" diameter 4130 steel tubing, with a wall
thickness
of 0.049", the cross-sectional area would be =F0 x (1.0002 - .9022)/4 or
.146
in2 . With 2,270 lbs being carried by .146 in2, the stress in that
strut
would be 2270/.146 or 15,505 psi. Since normalized 4130 has an ultimate
strength of 90,000 psi, this is certainly a safe load for that steel
strut
to carry.
So for wood or aluminum struts, you simply need to know the breaking
strength of the material and the cross-sectional area of the strut and
you
can calculate the stress.
Jack Phillips
NX899JP
Smith Mountain Lake, Virginia
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Mark
Roberts
Sent: Sunday, June 16, 2013 9:29 PM
Subject: Pietenpol-List: Re: wood vs steel struts
<mark.rbrts1@gmail.com>
Does anyone know what the actual stress pressures on the struts? The
aluminum struts seem to me quite strong for normal flight, but when I
compared the strength of the steel vs aluminum, there is so much
difference
I am curious by what factor is actually necessary? Anyone able to
calculate
the strength Needed by the struts?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402825#402825
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Subject: | Re: wood vs steel struts |
Excellent explanation.
Thank you,
Michael
-------------------------------------------------------------------------
-------
-------------------------------------------------------------------------
-------
From: Jack Phillips
Sent: Monday, June 17, 2013 4:54 AM
Subject: RE: Pietenpol-List: Re: wood vs steel struts
Fairly simple to calculate. First, figure out what gross weight your
airplane will have (in order to make this calculation conservative, pick
a number higher than you really think it will be). For the purpose of
this exercise, let's say the gross weight is 1300 lbs.
Then multiply that by the highest load factor (G-load) you would expect
to survive in extreme turbulence or maneuvers. 5 G's is a common number
for ultimate loading (the load that would cause something to break). So
this means the wing is carrying 1300 x 5 or 6,500 lbs of load.
Most of the wing load is carried by the lift struts. A Pietenpol has a
29' wingspan, with a 2' wide centersection, so each wing panel is 13' 6"
wide and carries 13.5/29 or 47% of the load, which in this example is
3,025 lbs.
Since the lift struts attach in the middle of the wing panel, virtually
all of the lift load is transferred to the struts, with very little load
carried by the bolts attaching the wing panel to the centersection (low
enough to be ignored in this example). So the two lift struts on each
side carry 3,025 lbs between them.
Calculating how much of that load is carried by the front strut and how
much by the rear is a bit more difficult. The distribution of load
varies with the location of the center of pressure, which moves around
as the angle of attack changes, and the location of the center of
gravity, which varies with how the airplane is loaded (fuel and
passengers, for example). It is probably safe to say that the front
strut carries up to about 3/4 of the wing load, since it is pretty close
to the C.G.
So that means with a 1300 lb Pietenpol loaded to 5 G's by turbulence or
extreme aerobatics, the front struts each are carrying (3/4)x(3,025) or
2,270 lbs.
OK, we've found the load the struts carry. The stress is simply that
load divided by the cross sectional area of the strut. For a round
tube, the area is easy to calculate: Area = =CF(d2outside
=93 d2inside)/4
Assuming you are using 1=9D diameter 4130 steel tubing, with a
wall thickness of 0.049=9D, the cross-sectional area would be
=CF x (1.0002 - .9022)/4 or .146 in2 . With 2,270 lbs being carried
by .146 in2, the stress in that strut would be 2270/.146 or 15,505 psi.
Since normalized 4130 has an ultimate strength of 90,000 psi, this is
certainly a safe load for that steel strut to carry.
So for wood or aluminum struts, you simply need to know the breaking
strength of the material and the cross-sectional area of the strut and
you can calculate the stress.
Jack Phillips
NX899JP
Smith Mountain Lake, Virginia
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Mark
Roberts
Sent: Sunday, June 16, 2013 9:29 PM
Subject: Pietenpol-List: Re: wood vs steel struts
<mark.rbrts1@gmail.com>
Does anyone know what the actual stress pressures on the struts? The
aluminum struts seem to me quite strong for normal flight, but when I
compared the strength of the steel vs aluminum, there is so much
difference I am curious by what factor is actually necessary? Anyone
able to calculate the strength Needed by the struts?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402825#402825
No virus found in this message.
Checked by AVG - www.avg.com
06/16/13
Message 6
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Subject: | Re: Latex Paint Forum |
I would be interested in your forum on this subject. Possible to do a video and
post it on YouTube for us not attending?
WF2
--------
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402854#402854
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Subject: | Re: Pietenpol Picnic |
It was great. I got to comb a pietenpol over and I got my first ride in
Brian's Piet C-FAUK... Was a great experience and a great motivator.....
----- Original Message -----
From: "Bill Church" <billspiet@sympatico.ca>
Sent: Sunday, June 16, 2013 9:40 PM
Subject: Pietenpol-List: Re: Pietenpol Picnic
> <billspiet@sympatico.ca>
>
> Weather co-operated. Sunny and comfortable temperatures all day. Bit of
> a crosswind. Lots of people turned out. Only two Piets present, but a
> selection of other interesting aircraft showed up.
>
> Unfortunately, I had a bit of mechanical trouble on the way, so I didn't
> arrive until almost 2pm. And once I had said hello to all the faces I
> knew, most of the aircraft had departed - so I have almost no photos to
> share. However, I did take a handful of photos. Here are a few snapped
> at the end of the day.
>
> Bill C.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=402827#402827
>
>
> Attachments:
>
> http://forums.matronics.com//files/img_4418_138.jpg
> http://forums.matronics.com//files/img_4426_269.jpg
> http://forums.matronics.com//files/img_4430_183.jpg
>
>
>
Message 8
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Subject: | Re: WW2 Jeep Gauges |
I have a O-200 any idea how the temperature gauge would work with the probe on
it?
Rodney Hall
---- TriScout <apfelcyber@yahoo.com> wrote:
>
> ......added pic's (clearer).......end msg
>
> --------
> L.Metzel
> KLNC
> A65-8
> N2308C
> AN Hardware
> Airframe 712TT
> W72CK-42 Sensenich
> Standard Factory GN-1
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=402823#402823
>
>
> Attachments:
>
> http://forums.matronics.com//files/1_214.jpg
> http://forums.matronics.com//files/photo_150.jpg
>
>
Message 9
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Subject: | Re: Still Learning to Fly |
Is this at Red Stewart or Dayton Wright Bro?
CB
----- Original Message -----
From: "John Francis" <Mrkringles@msn.com>
Sent: Sunday, June 16, 2013 2:47 PM
Subject: Pietenpol-List: Still Learning to Fly
>
> As Bob DeWenter announced last week, I finally soloed. Between Part 141
> and the flying schools' restrictions it became difficult to find a good
> time for me to solo. My solo was scheduled 7 times and cancelled due to
> strong winds
> (over 5 knot crosswind component) or a wind speed over 15 knots. It's
> been a windy Spring around here! Fortunately I was able to continue to
> fly and accumulate hours with my instructor waiting for the solo.
>
> I continue to gain confidence and improvement with each of my flights. I
> am sure looking forward to moving on to some cross country navigation and
> flights.
>
> Landings have been the most difficult part of flying for me. I just can't
> seem to get the knack of it. I'll probably just get it in the 172 when I
> transfer over to the Piper Cub for the rest of the training. Here is a
> good example of one of my landings. Bob is narrating and taking the
> video. He gets a little excited and thinks it is my third
> landing......but it is only my second. I hope he knows how much I
> appreciate having this on film. I had a gopro camera in my flight bag but
> forgot to take it out.
>
> http://www.youtube.com/watch?v=B_qzyyNBu0E
>
> The flying lessons have motivated me to work harder on my Piet build just
> like attending fly-ins, Brodhead, and EAA meets.
>
> --------
> John Francis
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=402806#402806
>
>
>
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Subject: | Re: WW2 Jeep Gauges |
That's a "penzon"..........penzon if you have an 0200A or not. The A has same limit
as A65... Up to 225deg limit. Later models go up to 240deg...and higher limitations
on certain models of that motor.
--------
L.Metzel
KLNC
A65-8
N2308C
AN Hardware
Airframe 712TT
W72CK-42 Sensenich
Standard Factory GN-1
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402859#402859
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Subject: | Re: Still Learning to Fly |
Dayton Wight Brothers Rwy 2
--------
John Francis
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402860#402860
Message 12
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Subject: | Re: WW2 Jeep Gauges |
Oh...windscreen. I'm out on a trip at moment...just have this apple product to
work with, or I would get some close shots of windscreen posted.
--------
L.Metzel
KLNC
A65-8
N2308C
AN Hardware
Airframe 712TT
W72CK-42 Sensenich
Standard Factory GN-1
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402861#402861
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Subject: | Re: 4130 tubing FOR SALE |
We are soon to do a production run here in the UK of 4130 lift strut tubing 2.69
x 1.44 x 0.049 if anyone is interested or you have a group requirement please
contact with quantity.
It may be very interesting if a good freight cost can be found.
--------
Building a Pietenpol-a lot to learn!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402864#402864
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Subject: | rudder & elevator hinges |
Can anyone advise what grade of aluminium is used for the cast hinges.
Has a machined hinge been used as a replacement ?
Thanks
Trevor
--------
Building a Pietenpol-a lot to learn!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402865#402865
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Subject: | Re: engine out.. |
My spars are douglas fir.. and I found some within an hour from here.
plan to pick of a board or 2 today and start scarfing.
the repair other than scarfing the joint that is still on the plane looks pretty
easy.
A couple of the pilots here at work are asking when i'm going to put an airplane
engine on it. I really hate to do that because the A is really cool.
I do know of an A75 locally that I could get for a good price.. needs overhaul,
but that's easy. I hope to keep the A.. going to tear it apart unless I find
an ignition or carb prob just to figure this out.
but the wing is first.. gotta have that no matter the engine choice.
I'm thinking a lot about the oil pressure.. or lack of..being the possible issue.
jeff
Read this topic online here:
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Subject: | Re: wood vs steel struts |
awesome breakdown jack!!!!
and thanks for your response as well Dan.
--------
Paul Donahue
Started 8-3-12
do not archive
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402867#402867
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Subject: | Re: wood vs steel struts |
Jack,
One thing you missed.....
The struts are at an angle to the wing, so this must be taken into account.
If the included=C2-angle is=C2-30 degrees down from the wing then you h
ave to divide the load by sin30.
Effectively this doubles the strut tension load from 2270 lbs to 4540 lbs.
Best regards,
John Woods
----- "Jack Phillips" <jack@bedfordlandings.com> wrote:
>
>
Fairly simple to calculate.=C2- First, figure out what gross weight your
airplane will have (in order to make this calculation conservative, pick a
number higher than you really think it will be).=C2- For the purpose of t
his exercise, let's say the gross weight is 1300 lbs.
Then multiply that by the highest load factor (G-load) you would expect to
survive in extreme turbulence or maneuvers.=C2- 5 G's is a common number
for ultimate loading (the load that would cause something to break).=C2-
So this means the wing is carrying 1300 x 5 or 6,500 lbs of load.
Most of the wing load is carried by the lift struts.=C2- A Pietenpol has
a 29' wingspan, with a 2' wide centersection, so each wing panel is 13' 6"
wide and carries 13.5/29 or 47% of the load, which in this example is 3,025
lbs.
Since the lift struts attach in the middle of the wing panel, virtually all
of the lift load is transferred to the struts, with very little load carri
ed by the bolts attaching the wing panel to the centersection (low enough t
o be ignored in this example).=C2- So the two lift struts on each side ca
rry 3,025 lbs between them.
Calculating how much of that load is carried by the front strut and how muc
h by the rear is a bit more difficult.=C2- The distribution of load varie
s with the location of the center of pressure, which moves around as the an
gle of attack changes, and the location of the center of gravity, which var
ies with how the airplane is loaded (fuel and passengers, for example).=C2
- It is probably safe to say that the front strut carries up to about 3/4
of the wing load, since it is pretty close to the C.G.
So that means with a 1300 lb Pietenpol loaded to 5 G's by turbulence or ext
reme aerobatics, the front struts each are carrying (3/4)x(3,025) or 2,270
lbs.
OK, we've found the load the struts carry.=C2- The stress is simply that
load divided by the cross sectional area of the strut.=C2- For a round tu
be, the area is easy to calculate:=C2- Area = =CF(d 2 outside
=93 d 2 inside )/4
Assuming you are using 1=9D diameter 4130 steel tubing, with a wall t
hickness of 0.049=9D, the cross-sectional area would be =CF x (1.0
00 2 - .902 2 )/4 or .146 in 2 .=C2- With 2,270 lbs being carried by .146
in 2 , the stress in that strut would be 2270/.146 or 15,505 psi.=C2- Si
nce normalized 4130 has an ultimate strength of 90,000 psi, this is certain
ly a safe load for that steel strut to carry.
So for wood or aluminum struts, you simply need to know the breaking streng
th of the material and the cross-sectional area of the strut and you can ca
lculate the stress.
Jack Phillips
NX899JP
Smith Mountain Lake, Virginia
-----Original Message-----
> From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-l
ist-server@matronics.com] On Behalf Of Mark Roberts
> Sent: Sunday, June 16, 2013 9:29 PM
> To: pietenpol-list@matronics.com
> Subject: Pietenpol-List: Re: wood vs steel struts
>
Does anyone know what the actual stress pressures on the struts? The alumin
um struts seem to me quite strong for normal flight, but when I compared th
e strength of the steel vs aluminum, there is so much difference I am curio
us by what factor is actually necessary? Anyone able to calculate the stren
gth Needed by the struts?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402825#402825
===
===
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==
Message 18
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Subject: | Re: wood vs steel struts |
Oops! Of course you are right, John. I wondered, because I remember
doing
the analysis years ago when I built my Pietenpol and it seemed like the
struts were a lot more highly loaded than that. That's what I get for
trying to work from memory, instead of drawing a free body diagram.
So in my example, the stress in the steel tube strut would be more like
31,000 psi, which is getting into significant stress range.
Jack Phillips
NX899JP
Smith Mountain Lake, Virginia
_____
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of John
Woods
Sent: Monday, June 17, 2013 5:15 PM
Subject: Re: Pietenpol-List: Re: wood vs steel struts
Jack,
One thing you missed.....
The struts are at an angle to the wing, so this must be taken into
account.
If the included angle is 30 degrees down from the wing then you have to
divide the load by sin30.
Effectively this doubles the strut tension load from 2270 lbs to 4540
lbs.
Best regards,
John Woods
----- "Jack Phillips" <jack@bedfordlandings.com> wrote:
>
>
Fairly simple to calculate. First, figure out what gross weight your
airplane will have (in order to make this calculation conservative, pick
a
number higher than you really think it will be). For the purpose of
this
exercise, let's say the gross weight is 1300 lbs.
Then multiply that by the highest load factor (G-load) you would expect
to
survive in extreme turbulence or maneuvers. 5 G's is a common number
for
ultimate loading (the load that would cause something to break). So
this
means the wing is carrying 1300 x 5 or 6,500 lbs of load.
Most of the wing load is carried by the lift struts. A Pietenpol has a
29'
wingspan, with a 2' wide centersection, so each wing panel is 13' 6"
wide
and carries 13.5/29 or 47% of the load, which in this example is 3,025
lbs.
Since the lift struts attach in the middle of the wing panel, virtually
all
of the lift load is transferred to the struts, with very little load
carried
by the bolts attaching the wing panel to the centersection (low enough
to be
ignored in this example). So the two lift struts on each side carry
3,025
lbs between them.
Calculating how much of that load is carried by the front strut and how
much
by the rear is a bit more difficult. The distribution of load varies
with
the location of the center of pressure, which moves around as the angle
of
attack changes, and the location of the center of gravity, which varies
with
how the airplane is loaded (fuel and passengers, for example). It is
probably safe to say that the front strut carries up to about 3/4 of the
wing load, since it is pretty close to the C.G.
So that means with a 1300 lb Pietenpol loaded to 5 G's by turbulence or
extreme aerobatics, the front struts each are carrying (3/4)x(3,025) or
2,270 lbs.
OK, we've found the load the struts carry. The stress is simply that
load
divided by the cross sectional area of the strut. For a round tube, the
area is easy to calculate: Area = =F0(d2outside - d2inside)/4
Assuming you are using 1" diameter 4130 steel tubing, with a wall
thickness
of 0.049", the cross-sectional area would be =F0 x (1.0002 - .9022)/4 or
.146
in2 . With 2,270 lbs being carried by .146 in2, the stress in that
strut
would be 2270/.146 or 15,505 psi. Since normalized 4130 has an ultimate
strength of 90,000 psi, this is certainly a safe load for that steel
strut
to carry.
So for wood or aluminum struts, you simply need to know the breaking
strength of the material and the cross-sectional area of the strut and
you
can calculate the stress.
Jack Phillips
NX899JP
Smith Mountain Lake, Virginia
-----Original Message-----
> From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Mark
Roberts
> Sent: Sunday, June 16, 2013 9:29 PM
> To: pietenpol-list@matronics.com
> Subject: Pietenpol-List: Re: wood vs steel struts
<mark.rbrts1@gmail.com>
Does anyone know what the actual stress pressures on the struts? The
aluminum struts seem to me quite strong for normal flight, but when I
compared the strength of the steel vs aluminum, there is so much
difference
I am curious by what factor is actually necessary? Anyone able to
calculate
the strength Needed by the struts?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402825#402825
" target=_blank>http://www.matronics.com/Navigator?Pietenpol-List
p://forums.matronics.com
blank>http://www.matronics.com/contribution
Message 19
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Need some help on where to mount the ELT and ELT antenna on my
Pietenpol. I had not intended to have an ELT based on reports from this
group that they were not required to have one by their DAR because of
staying within 25 miles of the home airport for the first 40 hours. Now
that my plane is finished (see attached pic), my DAR says I must have
one. So, I am essentially having to retrofit an ELT to a plane I didn't
design to have one.
At this point I am leaning toward putting the ELT between the legs of
the passenger on the floor of the front pit. For the antenna, I am
leaning toward mounting it on the forward portion of the coaming (tho it
will hurt to drill a mounting hole in my finished cowl), as that's the
only existing metal that is large enough to act as a ground plane.
I know its preferred (but not required) to mount the ELT as far aft as
possible, but at this point, I would have to do some major rework to
mount the ELT and create a ground plane anywhere behind the pilot, not
to mention the negative effect on CG.
I've gone through all the Matronics archives without finding a good
solution for my situation, so would invite any input on:
1. Where you mounted the ELT.
2. Where you mounted the ELT antenna.
3. What you used as a ground plane.
Especially if it's mounted in a forward location.
Larry Morlock
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Subject: | Re: wood vs steel struts |
Jack
As one of my engineering profs from back in the stone ages used to say about his
exams -- "No free body diagram, no credit!!!"
Dave
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402898#402898
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Larry,
I can't help you with the ELT, since mine is behind the pilot.but your Piet
sure turned out nice!!
Gary Boothe
NX308MB
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Larry
Morlock
Sent: Monday, June 17, 2013 3:07 PM
Subject: Pietenpol-List: ELT Location
Need some help on where to mount the ELT and ELT antenna on my Pietenpol. I
had not intended to have an ELT based on reports from this group that they
were not required to have one by their DAR because of staying within 25
miles of the home airport for the first 40 hours. Now that my plane is
finished (see attached pic), my DAR says I must have one. So, I am
essentially having to retrofit an ELT to a plane I didn't design to have
one.
At this point I am leaning toward putting the ELT between the legs of the
passenger on the floor of the front pit. For the antenna, I am leaning
toward mounting it on the forward portion of the coaming (tho it will hurt
to drill a mounting hole in my finished cowl), as that's the only existing
metal that is large enough to act as a ground plane.
I know its preferred (but not required) to mount the ELT as far aft as
possible, but at this point, I would have to do some major rework to mount
the ELT and create a ground plane anywhere behind the pilot, not to mention
the negative effect on CG.
I've gone through all the Matronics archives without finding a good solution
for my situation, so would invite any input on:
1. Where you mounted the ELT.
2. Where you mounted the ELT antenna.
3. What you used as a ground plane.
Especially if it's mounted in a forward location.
Larry Morlock
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Subject: | Re: engine out.. |
Jeff,
Either those guys that want you to change engines are secretly envious, or they
don't want to admit that they don't have the gonads to build and fly a real experimental!
(Not that there's anything wrong with a/c engines...that was simply
not your choice)
They sound like some of the same guys from my airport! I'm not an 'A' guy, but
I know there are plenty of guys on this list who are quite experienced, and just
waiting for you to ask some direct questions.
When you get the bugs worked out, like Dan Helsper did, those guys will be awed
by your cool-sounding engine, take credit for helping you to fix it, then move
on to the next airport to beat up on someone else...
Gary
NX308MB
Sent from my iPhone
On Jun 17, 2013, at 7:33 AM, "bender" <jfaith@solairusaviation.com> wrote:
>
> My spars are douglas fir.. and I found some within an hour from here.
> plan to pick of a board or 2 today and start scarfing.
> the repair other than scarfing the joint that is still on the plane looks pretty
easy.
> A couple of the pilots here at work are asking when i'm going to put an airplane
engine on it. I really hate to do that because the A is really cool.
> I do know of an A75 locally that I could get for a good price.. needs overhaul,
but that's easy. I hope to keep the A.. going to tear it apart unless I find
an ignition or carb prob just to figure this out.
> but the wing is first.. gotta have that no matter the engine choice.
> I'm thinking a lot about the oil pressure.. or lack of..being the possible issue.
>
> jeff
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=402866#402866
>
>
>
>
>
>
>
>
>
>
Message 23
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Subject: | Re: Latex Paint Forum |
WF2
I will see what I can do about recording the session. At a minimum I will have
an expanded and updated Powerpoint presentation available.
Malcolm
----- Original Message -----
From: "womenfly2" <Love2Fly.KAP@gmail.com>
Sent: Monday, June 17, 2013 9:19:57 AM
Subject: Pietenpol-List: Re: Latex Paint Forum
I would be interested in your forum on this subject. Possible to do a video and
post it on YouTube for us not attending?
WF2
--------
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402854#402854
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Subject: | Re: engine out.. |
Jeff,
I'm with Gary! If your airplane shows up at Brodhead without the Model A powering
it, we are going to drink all your home brew and shave your beard while you
sleep!
--------
Curt Merdan
Flower Mound, TX
Do Not Archive
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402906#402906
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Subject: | My "hood ornament" |
The dirty rotten fourflusher stole my flying pig!!
Mine's way cooler...
Douwe
Message 26
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Subject: | Re: wood vs steel struts |
Yep - that's a good rule. An FBD tends to point out such little things as
vector components, which would have cued me in on this one. I was so busy
thinking about how to explain how you get from the loading to the stresses
in the strut that I neglected to mention the huge effect the strut geometry
has on the loading (and the stresses).
As long as we're having this discussion, it's probably appropriate to
mention that one of the problems with wooden or aluminum struts is how to
make the attachments to the fittings. Almost invariably such attachments
have to be made with bolts loaded in shear, so the shear strength of the
wood or aluminum must be considered. It is not a trivial exercise.
Jack Phillips
NX899JP
Smith Mountain Lake, Virginia
A retired engineer, who perhaps should STAY retired
Jack
As one of my engineering profs from back in the stone ages used to say about
his exams -- "No free body diagram, no credit!!!"
Dave
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Subject: | My "hood ornament" |
...and goes higher.
Gary Boothe
NX308MB
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Douwe
Sent: Monday, June 17, 2013 5:46 PM
Subject: Pietenpol-List: My "hood ornament"
--> <douweblumberg@earthlink.net>
The dirty rotten fourflusher stole my flying pig!!
Mine's way cooler...
Douwe
Message 28
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Subject: | Re: wood vs steel struts |
Jack, if using steel struts, do you recommend welding in bushings for the straps
to bolt through, or is this creating a future location for a crack?
--------
Paul Donahue
Started 8-3-12
do not archive
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402911#402911
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Subject: | Sunset - send in your favorite photo |
An evocative pic to spur everyone towards the finish line (even if its the s
econd finish line). How 'bout everyone send in their favorite photo?
Douwe
Sent from my iPhone
<pre><b><font size=2 color="#000000" face="courier new,courier">
</b></font></pre></body></html>
Message 30
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Subject: | Re: wood vs steel struts |
It's too hard to recommend anything without seeing the design you are using.
Everybody's plane is different. I welded my struts (made from old J-3 Cub
front struts). Welds don't necessarily cause cracks if they're done right.
Jack Phillips
NX899JP
Smith Mountain Lake, Virginia
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of nightmare
Sent: Monday, June 17, 2013 9:15 PM
Subject: Pietenpol-List: Re: wood vs steel struts
<pauldonahuepilot@yahoo.com>
Jack, if using steel struts, do you recommend welding in bushings for the
straps to bolt through, or is this creating a future location for a crack?
--------
Paul Donahue
Started 8-3-12
do not archive
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402911#402911
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Subject: | Re: Sunset - send in your favorite photo |
>From Brodhead 2012.
Photo courtesy of Pat Hoyt.
Greg Cardinal
----- Original Message -----
From: "Douwe" <douweblumberg@earthlink.net>
Sent: Monday, June 17, 2013 8:42 PM
Subject: Pietenpol-List: Sunset - send in your favorite photo
An evocative pic to spur everyone towards the finish line (even if its the
second finish line). How 'bout everyone send in their favorite photo?
Douwe
--------------------------------------------------------------------------------
>
>
> Sent from my iPhone
> <pre><b><font size=2 color="#000000" face="courier new,courier">
>
> href="http://www.matronics.com/Navigator?Pietenpol-List">http://www.matronics.com/Navigator?Pietenpol-List</a>
> href="http://forums.matronics.com">http://forums.matronics.com</a>
> href="http://www.matronics.com/contribution">http://www.matronics.com/contribution</a>
>
> </b></font></pre></body></html>
Message 32
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Subject: | Re: wood vs steel struts |
I understand. Thanks Jack
--------
Paul Donahue
Started 8-3-12
do not archive
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=402917#402917
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