Today's Message Index:
----------------------
1. 03:24 AM - Re: New builder already needs help (helspersew@aol.com)
2. 04:34 AM - Re: New builder already needs help (gcardinal)
3. 05:15 AM - Re: Circuit breakers (Barry Davis)
4. 05:58 AM - Re: New builder already needs help (Jack Phillips)
5. 06:50 AM - converting an A65 to an A75 (Oscar Zuniga)
6. 06:56 AM - differeneces between C75 and C85 (Oscar Zuniga)
7. 07:16 AM - Re: New builder already needs help (Michael Perez)
8. 08:52 AM - Re: New builder already needs help (Myron Anderson)
9. 09:00 AM - Re: New builder already needs help (Bill Church)
10. 09:21 AM - Re: log your test maneuvers (Rick Holland)
11. 09:34 AM - Re: Re: New builder already needs help (Rick Holland)
12. 12:55 PM - 1/2" web idea. Spar options--one man's method (Cuy, Michael D. (GRC-RXD0)[ASRC Aerospace Corporation])
13. 01:14 PM - Re: 1/2" web idea. Spar options--one man's method (taildrags)
14. 01:42 PM - Re: 1/2" web idea. Spar options--one man's method (Dan Yocum)
15. 01:54 PM - Re: Re: 1/2" web idea. Spar options--one man's method (Cuy, Michael D. (GRC-RXD0)[ASRC Aerospace Corporation])
16. 02:50 PM - Re: Re: Purchased an Engine (Dale Johnson)
17. 05:44 PM - Re: 1/2" web idea. Spar options--one man's method (David Paule)
18. 06:37 PM - Re: 1/2" web idea. Spar options--one man's method (Dan Yocum)
19. 07:33 PM - Re: 1/2" web idea. Spar options--one man's method (David Paule)
20. 07:49 PM - Re: Re: 1/2" web idea. Spar options--one man's method (Dick N)
21. 09:06 PM - Re: 1/2" web idea. Spar options--one man's method (Baldeagle)
22. 09:59 PM - Re: Re: New builder already needs help (Mike Whaley)
Message 1
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Subject: | Re: New builder already needs help |
Myron,
Went with the 1" for authenticity. (Purist) The routing surely creates a
LOT of expensive sawdust to sweep up.
Dan Helsper
Poplar Grove, IL.
-----Original Message-----
From: Myron Anderson <myronanderson1@comcast.net>
Sent: Thu, Mar 11, 2010 10:25 pm
Subject: Pietenpol-List: New builder already needs help
After years of lurking about the matronics site, going to Oshkosh and drea
ming about building an airplane I have taken the plunge. My plans arrived
today and I am now officially building a piet.
While planning my first order to Aircraft Spruce and pouring over the plan
s and some builders web sites I have a question about spar size. I have
seen several mentions of the spar width of =C2=BE inches and the plans sh
ow spar width of 1 inch with some sections routed for weight savings. I
was going to order section of spar to aid in rib jig construction and to
test fit the ribs onto to check for consistency of my build. I figured
I would use the section of spar later for the center section if I decided
to go with the three piece wing. What width spar are you using?
Myron Anderson
Plans in hand and preparing to make ribs.
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Message 2
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Subject: | Re: New builder already needs help |
Spar size is builder's choice. 3/4" will be less expensive to purchase.
Decide on your spar size and then build the ribs accordingly.
Greg Cardinal
Minneapolis
----- Original Message -----
From: Myron Anderson
To: pietenpol-list@matronics.com
Sent: Thursday, March 11, 2010 10:25 PM
Subject: Pietenpol-List: New builder already needs help
After years of lurking about the matronics site, going to Oshkosh and
dreaming about building an airplane I have taken the plunge. My plans
arrived today and I am now officially building a piet.
While planning my first order to Aircraft Spruce and pouring over the
plans and some builders web sites I have a question about spar size. I
have seen several mentions of the spar width of =BE inches and the plans
show spar width of 1 inch with some sections routed for weight savings.
I was going to order section of spar to aid in rib jig construction and
to test fit the ribs onto to check for consistency of my build. I
figured I would use the section of spar later for the center section if
I decided to go with the three piece wing. What width spar are you
using?
Myron Anderson
Plans in hand and preparing to make ribs.
Message 3
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Subject: | Circuit breakers |
Looking at the AeroMax Corvair Service and Operations Manual, the wiring
diagram shows a 3amp Breaker between the A/B switch(we used a ON/ON switch)
and the coils (one for each coil). That is the way we did ours. I always
pull these out if there are a lot of kids around and I can't watch the Big
Piet every minute.
Barry Davis
Big Piet
NX973BP
The pic shows the switch and breakers labled "P" and "E" for points and
electronic (also marked the coils P&E, every little bit helps later on). The
40amp breaker is for the alternator. Hope this helps.
-----Original Message-----
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of skellytown
flyer
Sent: Thursday, March 11, 2010 7:34 PM
Subject: Pietenpol-List: Circuit breakers
--> <skellflyer1@yahoo.com>
if any of you have installed circuit breakers to your coils on Corvair
conversions I'd like to hear what you used.I have the coil switcher with 2
coils and 2 ignition switches.but I'm thinking at a minimum I will install
individual panel mounted fuses that can be easily changed from the seat.no
doubt should get breakers but then I am still a tightwad and with the dual
coils if one shorts it probably wouldn't stay reset anyway.what's the
opinions? and what kind of amp rating? Raymond
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=290065#290065
Message 4
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Subject: | New builder already needs help |
=BE=94 is plenty, and considerably cheaper and ligther than 1=94
Jack Phillips
NX899JP
Raleigh, NC
_____
From: owner-pietenpol-list-server@matronics.com
[mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Myron
Anderson
Sent: Thursday, March 11, 2010 11:25 PM
Subject: Pietenpol-List: New builder already needs help
After years of lurking about the matronics site, going to Oshkosh and
dreaming about building an airplane I have taken the plunge. My plans
arrived today and I am now officially building a piet.
While planning my first order to Aircraft Spruce and pouring over the
plans
and some builders web sites I have a question about spar size. I have
seen
several mentions of the spar width of =BE inches and the plans show spar
width
of 1 inch with some sections routed for weight savings. I was going to
order section of spar to aid in rib jig construction and to test fit the
ribs onto to check for consistency of my build. I figured I would use
the
section of spar later for the center section if I decided to go with the
three piece wing. What width spar are you using?
Myron Anderson
Plans in hand and preparing to make ribs.
Message 5
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|
Subject: | converting an A65 to an A75 |
>From my upcoming article on the small Continentals
in Contact! Magazine:
======================
In order to obtain ten additional horsepower by
turning the A65 at 2600 RPM rather than at 2300,
Continental changed several things related to cooling
and lubrication. The cap ends of the rods were
drilled with 1/16 holes to provide additional squirt
lubrication for the cylinder walls, the exhaust valves
were changed to stellite-faced (a cobalt-chromium alloy
with increased hardness and a high melting point), and
the undersides of the pistons were made with a waffle
pattern for additional cooling. The wrist pins were
also changed to a smaller diameter, although it is
possible to create a pseudo-A75 from an A65 by simply
changing the valves and drilling the connecting rods
to allow the engine to operate at the higher RPM without
changing pistons, rods, or wrist pins, but engine life
and cooling may suffer. Once again, minor changes to
ignition timing and carburetion differentiate the
higher-horsepower engine from its predecessor. The
external appearance is unchanged, and other than by
examining the engine data plate, it is not possible to
distinguish one engine from the other. While many A65s
have been made to operate at the higher engine speed by
simply changing propellers to obtain A75 performance,
one must understand that the Continental engineers had
reasons for implementing the various changes to the engine
to achieve certification at the higher horsepower, and
countless hours of operation in all sorts of aircraft and
configurations brought to light the weaknesses that led
to the changes in later engines.
====================
If you have a certified engine, the conversion
must be done according to the Continental book
procedure and the logs signed off accordingly, or
otherwise you have an experimental engine.
Oscar Zuniga
Air Camper NX41CC
San Antonio, TX
mailto: taildrags@hotmail.com
website at http://www.flysquirrel.net
Message 6
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Subject: | differeneces between C75 and C85 |
Also from my upcoming article in Contact!,
referring to the jump from the A-series (O-170)
to the C-series (O-190):
================
The C75 and C85 introduced cylinders and pistons
with a new bore diameter of 4-1/16 to the series,
increasing displacement to 188 cubic inches and thus
the O-190 designation. With the increased bore and
displacement, the C75 could achieve rated power at
an A65-like engine speed of 2275 RPM. The jump from
the C75 to the C85 was very easily achieved by simply
changing the venturi and main jet in the Stromberg
carb (or by using an approved model of Marvel-Schebler
carb similar to those that would later be used in the
C90 and O-200 engines) and operating the engine at
2575 RPM.
===================
Oscar Zuniga
Air Camper NX41CC
San Antonio, TX
mailto: taildrags@hotmail.com
website at http://www.flysquirrel.net
Message 7
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Subject: | Re: New builder already needs help |
I am using 3/4" solid.
Message 8
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Subject: | Re: New builder already needs help |
Thanks All,
Since the price of spars are the same at Aircraft Spruce I have decided to
go with the 1 inch spar and do the routing. My order is in for the rib
materials and looking forward to getting started.
Myron Anderson
Danville, IN
Subject:
Re: New builder already needs help
From:
helspersew@aol.com
<mailto:helspersew@aol.com?subject=Re:%20New%20builder%20already%20needs%20h
elp&replyto=8CC8FED56EC0EDD-4E98-A2B5@webmail-m027.sysops.aol.com>
Date:
Fri Mar 12 - 3:24 AM
Myron,
Went with the 1" for authenticity. (Purist) The routing surely creates a
LOT of expensive sawdust to sweep up.
Dan Helsper
Poplar Grove, IL.
-----Original Message-----
From: Myron Anderson <myronanderson1@comcast.net
<mailto:myronanderson1@comcast.net?subject=Re:%20New%20builder%20already%20n
eeds%20help&replyto=8CC8FED56EC0EDD-4E98-A2B5@webmail-m027.sysops.aol.com> >
<mailto:pietenpol-list@matronics.com?subject=Re:%20New%20builder%20already%2
0needs%20help&replyto=8CC8FED56EC0EDD-4E98-A2B5@webmail-m027.sysops.aol.com>
Sent: Thu, Mar 11, 2010 10:25 pm
Subject: New builder already needs help
After years of lurking about the matronics site, going to Oshkosh and drea
ming about building an airplane I have taken the plunge. My plans arrived
today and I am now officially building a piet.
While planning my first order to Aircraft Spruce and pouring over the plan
s and some builders web sites I have a question about spar size. I have
seen several mentions of the spar width of =C2=BE inches and the plans sh
ow spar width of 1 inch with some sections routed for weight savings. I
was going to order section of spar to aid in rib jig construction and to
test fit the ribs onto to check for consistency of my build. I figured
I would use the section of spar later for the center section if I decided
to go with the three piece wing. What width spar are you using?
Myron Anderson
Plans in hand and preparing to make ribs.
Message 9
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Subject: | Re: New builder already needs help |
Myron,
If you purchased the full set of Pietenpol plans (including the three-piece wing
plan), you will see both versions of the spar (1" thick, and 3/4" thick). The
original design was 1" thick, with routed sections to reduce weight. This was
the spar drawn in the FGM drawings as well as in the 1933/34 Improved Air Camper
drawings. Later, BHP switched to a 3/4" thick spar, with NO routed sections.
The 3/4" spar is only shown in the drawing for the three-piece wing. The
3/4" non-routed spar has approximately 90% the strength of the routed 1" spar
(in simple bending). Both have been proven to be more than adequate in strength.
Which one to use is strictly up to you.
Your ribs can be built to accommodate the 1" spar, and then, later, if you decide
to use 3/4" spars, just add 1/2" wide, 1/8" plywood spacer shims at each rib
location. Or, if you know for certain that you want to use the 3/4" spar, build
your ribs to suit, and eliminate the little bit of extra weight and work of
the shims.
Bill C.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=290119#290119
Message 10
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Subject: | Re: log your test maneuvers |
Or his checkbook.
On Thu, Mar 11, 2010 at 7:29 PM, Gene & Tammy
<zharvey@bentoncountycable.net> wrote:
> <zharvey@bentoncountycable.net>
>
> That's what you hope the other guy has when he taxis into ya.
> Gene
> ----- Original Message ----- From: "Jeff Boatright" <jboatri@emory.edu>
> To: <pietenpol-list@matronics.com>
> Sent: Thursday, March 11, 2010 12:14 PM
> Subject: Re: Pietenpol-List: log your test maneuvers
>
>
>>
>> What's insurance?
>>
>>
>>
>>
>>
>>
>
>
> --------------------------------------------------------------------------------
>
>
> Checked by AVG - www.avg.com
> 21:50:00
>
>
--
Rick Holland
Castle Rock, Colorado
"Logic is a wreath of pretty flowers, that smell bad"
Message 11
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Subject: | Re: New builder already needs help |
Either size works fine. I think someone on this group who routed his
1" spars collected and weighted the shavings he routed out to see how
much weight he saved, came to less than a pound I believe. Can be
found in the archives.
rick
On Fri, Mar 12, 2010 at 12:00 PM, Bill Church <billspiet@sympatico.ca> wrote:
>
> Myron,
>
> If you purchased the full set of Pietenpol plans (including the three-piece wing
plan), you will see both versions of the spar (1" thick, and 3/4" thick).
The original design was 1" thick, with routed sections to reduce weight. This
was the spar drawn in the FGM drawings as well as in the 1933/34 Improved Air
Camper drawings. Later, BHP switched to a 3/4" thick spar, with NO routed sections.
The 3/4" spar is only shown in the drawing for the three-piece wing. The
3/4" non-routed spar has approximately 90% the strength of the routed 1" spar
(in simple bending). Both have been proven to be more than adequate in strength.
> Which one to use is strictly up to you.
> Your ribs can be built to accommodate the 1" spar, and then, later, if you decide
to use 3/4" spars, just add 1/2" wide, 1/8" plywood spacer shims at each
rib location. Or, if you know for certain that you want to use the 3/4" spar,
build your ribs to suit, and eliminate the little bit of extra weight and work
of the shims.
>
> Bill C.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=290119#290119
>
>
--
Rick Holland
Castle Rock, Colorado
"Logic is a wreath of pretty flowers, that smell bad"
Message 12
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Subject: | 1/2" web idea. Spar options--one man's method |
Myron, Group----here is how I did my spar and how I would do it again propo
sed in the attached sketch.
I did a cost analysis of both methods and it was pretty much a wash as I re
call with the proposed method
being way less work by not having to route out U-channels in those upper an
d lower 'caps'.
Mike C.
Message 13
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Subject: | Re: 1/2" web idea. Spar options--one man's method |
Mikee-
Wouldn't a dado blade on a table saw make much quicker work of the channels in
the spar caps than a router would, to accept the spar webs?
--------
Oscar Zuniga
San Antonio, TX
Air Camper NX41CC
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=290145#290145
Message 14
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Subject: | Re: 1/2" web idea. Spar options--one man's method |
Has anybody done the finite element analysis on the strength provided by
this method, Mike's second, in his picture? I was pondering this just
last night...
On 03/12/2010 02:48 PM, Cuy, Michael D. (GRC-RXD0)[ASRC Aerospace
Corporation] wrote:
> Myron, Group----here is how I did my spar and how I would do it again proposed
in the attached sketch.
>
> I did a cost analysis of both methods and it was pretty much a wash as I recall
with the proposed method
> being way less work by not having to route out U-channels in those upper and
lower 'caps'.
>
> Mike C.
>
>
--
Dan Yocum
Fermilab 630.840.6509
yocum@fnal.gov, http://fermigrid.fnal.gov
"I fly because it releases my mind from the tyranny of petty things."
Message 15
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Subject: | Re: 1/2" web idea. Spar options--one man's method |
Oscar,
Yes, a dado blade would have worked much faster on making those U channels but
I did not
have one at the time so used my router.
The beauty of gluing those four strips of spruce to each corner of the 1/2" spar
web is that
you don't need to dado or route anything.
Mike C.
Message 16
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Subject: | Re: Purchased an Engine |
Shad
There are other . The jets in the carb are larger also.
Dale
> [Original Message]
> From: shad bell <aviatorbell@yahoo.com>
> To: <pietenpol-list@matronics.com>
> Date: 3/11/2010 7:47:51 PM
> Subject: Re: Pietenpol-List: Re: Purchased an Engine
>
>
> I think the only physical difference between the a-65 nad a-75 was the
addition of a oil passage drilled in the rods (at the bearing caps) for
better lubrication, I also believe that a 65 can be modified to a 75. I
looked a buying a luscomb a few years back, and was studying up on it.
>
> Shad
>
>
>
>
>
Message 17
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Subject: | Re: 1/2" web idea. Spar options--one man's method |
Finite element analysis isn't necessary. Hand analysis would be considerably
easier and as accurate.
As it turns out, the two ways to build that spar are equivalent.
With the first approach, there doesn't seem to be a technical reason to make
the dado 3/4" deep. All that's needed is to locate the web and provide
enough glue area to ensure a firm bond. Since most glues likely to be used
will be stronger than the wood in in-plane shear, a person could even glue
the caps to the web without the dado, if they hold the position while
clamping. But a nominal small dado would be better. Smaller dados would let
the builder make the web shallower, too, and therefore probably cheaper.
David Paule
>
> Has anybody done the finite element analysis on the strength provided by
> this method, Mike's second, in his picture? I was pondering this just
> last night...
Message 18
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Subject: | Re: 1/2" web idea. Spar options--one man's method |
David,
On 03/12/2010 07:43 PM, David Paule wrote:
>
> Finite element analysis isn't necessary. Hand analysis would be
> considerably easier and as accurate.
I admit, the "finite element analysis" bit was tongue-in-cheek. I'm
much more of a back-of-the-envelope or napkin type of guy.
>
> As it turns out, the two ways to build that spar are equivalent.
Would these both be equivalent, or nearly so, to the 1"-wide-routed-out
method prescribed by BHP? I get that the glue joint would be stronger
than the wood, but would the overall strength of the resulting I-beam be
equivalent to a solid piece of wood that's scalloped out?
Thanks,
Dan
>
> With the first approach, there doesn't seem to be a technical reason to
> make the dado 3/4" deep. All that's needed is to locate the web and
> provide enough glue area to ensure a firm bond. Since most glues likely
> to be used will be stronger than the wood in in-plane shear, a person
> could even glue the caps to the web without the dado, if they hold the
> position while clamping. But a nominal small dado would be better.
> Smaller dados would let the builder make the web shallower, too, and
> therefore probably cheaper.
>
> David Paule
>
>
>>
>> Has anybody done the finite element analysis on the strength provided
>> by this method, Mike's second, in his picture? I was pondering this
>> just last night...
>
>
--
Dan Yocum
Fermilab 630.840.6509
yocum@fnal.gov, http://fermigrid.fnal.gov
"I fly because it releases my mind from the tyranny of petty things."
Message 19
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Subject: | Re: 1/2" web idea. Spar options--one man's method |
If the net cross-sections are the same and if the wood's grain is running
the same direction, then they are equivalent. I don't know what the original
routed section is so I can't comment about that.
David Paule
>> As it turns out, the two ways to build that spar are equivalent.
>
> Would these both be equivalent, or nearly so, to the 1"-wide-routed-out
> method prescribed by BHP? I get that the glue joint would be stronger
> than the wood, but would the overall strength of the resulting I-beam be
> equivalent to a solid piece of wood that's scalloped out?
>
> Thanks,
> Dan
>
Message 20
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Subject: | Re: 1/2" web idea. Spar options--one man's method |
Oscar
Thats how I did mine.
Dick N.
----- Original Message -----
From: "taildrags" <taildrags@hotmail.com>
Sent: Friday, March 12, 2010 3:14 PM
Subject: Pietenpol-List: Re: 1/2" web idea. Spar options--one man's method
>
> Mikee-
>
> Wouldn't a dado blade on a table saw make much quicker work of the
> channels in the spar caps than a router would, to accept the spar webs?
>
> --------
> Oscar Zuniga
> San Antonio, TX
> Air Camper NX41CC
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=290145#290145
>
>
>
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Subject: | Re: 1/2" web idea. Spar options--one man's method |
The "Spirit of St. Louis" spars are done like Mike's second sketch. 1/2" web,
3/4" corner pieces, total 2" thick at top and bottom of spar. Good enough for
Lindbergh and 450 gallons of gasoline.
-
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http://forums.matronics.com/viewtopic.php?p=290171#290171
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Subject: | Re: New builder already needs help |
When I worked for Steen Aero, the company airplane (Hale Wallace's last
Skybolt, N3HW) had routed spars. While it's never had problems, Hale and
others agreed (after the fact) that it was a fundamental mistake to do this.
In the end you only save a very small amount of weight (I think it was under
2 lbs, even for a biplane), and it can (potentially) significantly reduce
the rigidity of the spars. You also risk messing up while doing the routing
process and converting the piece to very expensive scrap wood!! Obviously
it's worked on many aircraft over the decades, but really, why risk it for
such a miniscule advantage and high potential cost?
I'd say that if you really want the beefiness of 1" spars but the lighter
weight of 3/4" spars, you'd be better off making your spars 7/8" thick,
without routing them. Or not worrying about it and going with the 1"...
seems to me that the spar is one of those things where a little extra
strength really isn't a bad thing at all, and the weight difference would be
better made up on other things. On my project, I believe I'll probably end
up with laminated spars, as this reduces the chances of a hidden defect
buried in the wood, you can use shorter wood pieces, they weight the same,
they fail progressively rather than completely at once (hopefully that will
never be an issue!) and they are more warp-resistant. Strength is at least
as strong as a solid spar, and with the tests from the Skybolt laminated
spars, it was found they were usually about 25% stronger than the solid
versions.
Mike Whaley
MerlinFAC@cfl.rr.com
----- Original Message -----
From: "Rick Holland" <at7000ft@gmail.com>
Sent: Friday, March 12, 2010 12:31 PM
Subject: [piet] Re: Pietenpol-List: Re: New builder already needs help
>
> Either size works fine. I think someone on this group who routed his
> 1" spars collected and weighted the shavings he routed out to see how
> much weight he saved, came to less than a pound I believe. Can be
> found in the archives.
>
> rick
>
> On Fri, Mar 12, 2010 at 12:00 PM, Bill Church <billspiet@sympatico.ca>
wrote:
<billspiet@sympatico.ca>
> >
> > Myron,
> >
> > If you purchased the full set of Pietenpol plans (including the
three-piece wing plan), you will see both versions of the spar (1" thick,
and 3/4" thick). The original design was 1" thick, with routed sections to
reduce weight. This was the spar drawn in the FGM drawings as well as in the
1933/34 Improved Air Camper drawings. Later, BHP switched to a 3/4" thick
spar, with NO routed sections. The 3/4" spar is only shown in the drawing
for the three-piece wing. The 3/4" non-routed spar has approximately 90% the
strength of the routed 1" spar (in simple bending). Both have been proven to
be more than adequate in strength.
> > Which one to use is strictly up to you.
> > Your ribs can be built to accommodate the 1" spar, and then, later, if
you decide to use 3/4" spars, just add 1/2" wide, 1/8" plywood spacer shims
at each rib location. Or, if you know for certain that you want to use the
3/4" spar, build your ribs to suit, and eliminate the little bit of extra
weight and work of the shims.
> >
> > Bill C.
> >
> >
> >
> >
> > Read this topic online here:
> >
> > http://forums.matronics.com/viewtopic.php?p=290119#290119
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
>
>
> --
> Rick Holland
> Castle Rock, Colorado
>
> "Logic is a wreath of pretty flowers, that smell bad"
>
>
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