epoxy aircraft seats?

where can I find construction details - howto files?

Try downloading the Quicke construction manual. It's not much more than a seat
with wings.

www.finleynet.com

"Lpmcatee356" wrote in message
...
where can I find construction details - howto files?

Try downloading the Quicke construction manual. It's not much more than a
seat
with wings.

www.finleynet.com


I used an ergonomically designed race-car seat as a mold and laid one up
using Rutan cloth and epoxy, then reinforced it with foam and a few more
layers of glass. The best way to learn about glass layups and molds is
reading Rutan's treatise on moldless foam construction and watching Mike
Arnold's AR-5 videotapes. Btw, the strength is not in the epoxy but in the
fiberglas. Or S-glass, or carbon fiber. However the resin matrix permits
the fibers to realize their strength.

At its website Cessna explains why it uses exclusively aluminum
construction. Cessna says there are too many unknowns regarding glass and
that aluminum is better. Well, aluminum IS better in some respects, but
glass is also better in many respects too. Fiberglas is easy to repair, it
lends itself nicely to compound curves, it does not corrode or fatigue like
aluminum, it is capable of absorbing more shock than aluminum, and its
strength-to-weight ratio cannot be beat.

Plus, when is the last time you saw a laminar flow wing made of aluminum?

You have to be very careful not to get your glass layup overweight. You
have to be very careful not to let your glass ship get hot in the sun. You
have to be very careful not to let UV rays eat the resin. But then,
composite construction must be viable or you wouldn't see so many Lancairs,
Cirruses, White Lightnings, Pulsars, and Eezies boring holes through the
sky.

Composite construction is labor-intensive, and that's part of the reason why
Boeing and M-D haven't migrated to it completely. Give them time.

On Sat, 29 Nov 2003 14:17:48 -0500, Larry Smith wrote:


"Lpmcatee356" wrote in message
...
where can I find construction details - howto files?

Try downloading the Quicke construction manual. It's not much more than
a
seat
with wings.

www.finleynet.com


At its website Cessna explains why it uses exclusively aluminum
construction. Cessna says there are too many unknowns regarding glass
and that aluminum is better. Well, aluminum IS better in some respects,
but glass is also better in many respects too. Fiberglas is easy to
repair, it lends itself nicely to compound curves, it does not corrode or
fatigue like aluminum, it is capable of absorbing more shock than
aluminum, and its strength-to-weight ratio cannot be beat.


There is no doubt fibreglas construction has its advantages, but I'm not
so sure that light weight is one of them. My impression from comparing
specs of similar aircraft is that aluminum construction is usually
lighter. For example, if we look at two seat, side-by-side fixed gear
aircraft, the RV-6 seems to come out at least 100 lb lighter than a
Glasair II TD if we have similar engines and props. And the RV-6 has a
lot more wing (110 sq. ft. vs 81 sq. ft).

http://www.airsport.com/kits/ksuper2.htm
http://www.vansaircraft.com/public/rv-6spe.htm

The Zenair CH2000 and the Diamond DA-20 were both designed to meet the
same requirements (JAR-VLA). The aluminum CH2000 is about 100 lb lighter
than the composite DA-20:

http://www.newplane.com/amd/spec.html
http://www.diamondair.com/contentc/c1spec.htm

--
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/
e-mail: khorton02(_at_)rogers(_dot_)com

"Kevin Horton" wrote in message
news
On Sat, 29 Nov 2003 14:17:48 -0500, Larry Smith wrote:


"Lpmcatee356" wrote in message
...
where can I find construction details - howto files?

Try downloading the Quicke construction manual. It's not much more
than
a
seat
with wings.

www.finleynet.com


At its website Cessna explains why it uses exclusively aluminum
construction. Cessna says there are too many unknowns regarding glass
and that aluminum is better. Well, aluminum IS better in some
respects,
but glass is also better in many respects too. Fiberglas is easy to
repair, it lends itself nicely to compound curves, it does not corrode
or
fatigue like aluminum, it is capable of absorbing more shock than
aluminum, and its strength-to-weight ratio cannot be beat.


There is no doubt fibreglas construction has its advantages, but I'm not
so sure that light weight is one of them. My impression from comparing
specs of similar aircraft is that aluminum construction is usually
lighter. For example, if we look at two seat, side-by-side fixed gear
aircraft, the RV-6 seems to come out at least 100 lb lighter than a
Glasair II TD if we have similar engines and props. And the RV-6 has a
lot more wing (110 sq. ft. vs 81 sq. ft).

http://www.airsport.com/kits/ksuper2.htm
http://www.vansaircraft.com/public/rv-6spe.htm

The Zenair CH2000 and the Diamond DA-20 were both designed to meet the
same requirements (JAR-VLA). The aluminum CH2000 is about 100 lb lighter
than the composite DA-20:

http://www.newplane.com/amd/spec.html
http://www.diamondair.com/contentc/c1spec.htm

--
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/
e-mail: khorton02(_at_)rogers(_dot_)com


I don't disagree with you here at all. It is true that most composite
kitplanes and most composite factory-built aircraft are a little heavier
than similar aluminum aircraft. However, you will find that careful layups
like those in the lighter Longezes and Variezes, and indeed in Rutan's
Voyager, will produce an aircraft lighter and stronger than aluminum.
Matter of fact you can't really make a comparison because of the variations
and the dissimilar advantages and disadvantages in each method of
construction.

Let me ask you something. Do you believe an aircraft like the
around-the-world Voyager could have been constructed of aluminum? Has
anyone ever built an aluminum Quickie or Cozy or Velocity?

I'll give you another example --- Mike Arnold's 213 mph world champion
speedster, the AR-5. Do you believe that same airframe, which is very
light, btw, because of judicious (but not vacuum-bagged) layups, could have
been made of aluminum? I don't. The AR-5 defeated the previous world
record-holder, which was an aluminum BD-5. Aluminum and compound curves
don't mix. Aluminum and laminar flow airfoils don't mix either. So I'd
say that the composite aircraft 100 pounds heavier than the RV-6 is faster
on the same engine and prop combination. I may be wrong. At least you can
hide antennas inside the airframe.

Not taking anything away from 2024-T3, of course. Duralumin is still a
miracle material for aircraft construction. And, having recorded the "From
the Ground Up" series with Joe Schumacher and Mark Annick, I'm envious of
your RV-8 project.

On Sat, 29 Nov 2003 18:20:53 -0500, Larry Smith wrote:


"Kevin Horton" wrote in message
news
On Sat, 29 Nov 2003 14:17:48 -0500, Larry Smith wrote:


At its website Cessna explains why it uses exclusively aluminum
construction. Cessna says there are too many unknowns regarding
glass and that aluminum is better. Well, aluminum IS better in some
respects,
but glass is also better in many respects too. Fiberglas is easy to
repair, it lends itself nicely to compound curves, it does not corrode
or
fatigue like aluminum, it is capable of absorbing more shock than
aluminum, and its strength-to-weight ratio cannot be beat.


There is no doubt fibreglas construction has its advantages, but I'm not
so sure that light weight is one of them. My impression from comparing
specs of similar aircraft is that aluminum construction is usually
lighter. For example, if we look at two seat, side-by-side fixed gear
aircraft, the RV-6 seems to come out at least 100 lb lighter than a
Glasair II TD if we have similar engines and props. And the RV-6 has a
lot more wing (110 sq. ft. vs 81 sq. ft).

http://www.airsport.com/kits/ksuper2.htm
http://www.vansaircraft.com/public/rv-6spe.htm

The Zenair CH2000 and the Diamond DA-20 were both designed to meet the
same requirements (JAR-VLA). The aluminum CH2000 is about 100 lb
lighter than the composite DA-20:

http://www.newplane.com/amd/spec.html
http://www.diamondair.com/contentc/c1spec.htm

--
Kevin Horton RV-8 (finishing kit) Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/ e-mail:
khorton02(_at_)rogers(_dot_)com


I don't disagree with you here at all. It is true that most composite
kitplanes and most composite factory-built aircraft are a little heavier
than similar aluminum aircraft. However, you will find that careful
layups like those in the lighter Longezes and Variezes, and indeed in
Rutan's Voyager, will produce an aircraft lighter and stronger than
aluminum. Matter of fact you can't really make a comparison because of the
variations and the dissimilar advantages and disadvantages in each method
of construction.

Let me ask you something. Do you believe an aircraft like the
around-the-world Voyager could have been constructed of aluminum? Has
anyone ever built an aluminum Quickie or Cozy or Velocity?

I'll give you another example --- Mike Arnold's 213 mph world champion
speedster, the AR-5. Do you believe that same airframe, which is very
light, btw, because of judicious (but not vacuum-bagged) layups, could
have been made of aluminum? I don't. The AR-5 defeated the previous
world record-holder, which was an aluminum BD-5. Aluminum and compound
curves don't mix. Aluminum and laminar flow airfoils don't mix either.
So I'd say that the composite aircraft 100 pounds heavier than the RV-6 is
faster on the same engine and prop combination. I may be wrong. At
least you can hide antennas inside the airframe.

Not taking anything away from 2024-T3, of course. Duralumin is still a
miracle material for aircraft construction. And, having recorded the
"From the Ground Up" series with Joe Schumacher and Mark Annick, I'm
envious of your RV-8 project.

I certainly agree that if your design needs very smooth exterior surfaces
or compound curves that you need to use some sort of composite.

And yes, the Voyager was a very light design. But was it really
fibreglas as you were originally talking about? I thought it had
graphite skins.

http://www.compositesengineering.com/Pages/Links.html

Some aluminum aircraft manage a good speed. Kent Paser made a long series
of incremental mods to his Mustang II and eventually had it doing 239 mph
at 8,000 ft on a 160 hp O-320. I wonder what the fastest fixed gear
Glasair does at 8,000 ft with an O-320.

So, lets agree - if you want the fastest speed, composite is probably
better. If you want the lightest weight, a review of similar
designs shows that aluminum usually wins.

--
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/
e-mail: khorton02(_at_)rogers(_dot_)com

One has to also consider the quality of workmanship, composite designs are
generally overdesigned because the designer is trying to cover differances
in workmanship from builder to builder. With aluminum, the same thickness
aluminum will yield the same strength part, but with composites differences
in technique and preparation can yield widely different results with the
same materials and number of layups. Designers compensate for this in the
beginning, IMHO this is the main reason why a composite will weigh more than
an equivilant aluminum structure. This is just a generalization that applies
mainly to amatuer built wet layups, in more controlled conditions(prepreg
carbon, vacuum bagged parts) the composite part can be lighter and stronger
than a similar aluminum part. However most homebuilders do not have access
to low cost supplies, tooling, and an oven large enough to do a complete
fuse, wing, etc... YMMV

Paul Hastings
"Kevin Horton" wrote in message
news
On Sat, 29 Nov 2003 18:20:53 -0500, Larry Smith wrote:


"Kevin Horton" wrote in message
news
On Sat, 29 Nov 2003 14:17:48 -0500, Larry Smith wrote:


At its website Cessna explains why it uses exclusively aluminum
construction. Cessna says there are too many unknowns regarding
glass and that aluminum is better. Well, aluminum IS better in some
respects,
but glass is also better in many respects too. Fiberglas is easy to
repair, it lends itself nicely to compound curves, it does not
corrode
or
fatigue like aluminum, it is capable of absorbing more shock than
aluminum, and its strength-to-weight ratio cannot be beat.


There is no doubt fibreglas construction has its advantages, but I'm
not
so sure that light weight is one of them. My impression from comparing
specs of similar aircraft is that aluminum construction is usually
lighter. For example, if we look at two seat, side-by-side fixed gear
aircraft, the RV-6 seems to come out at least 100 lb lighter than a
Glasair II TD if we have similar engines and props. And the RV-6 has a
lot more wing (110 sq. ft. vs 81 sq. ft).

http://www.airsport.com/kits/ksuper2.htm
http://www.vansaircraft.com/public/rv-6spe.htm

The Zenair CH2000 and the Diamond DA-20 were both designed to meet the
same requirements (JAR-VLA). The aluminum CH2000 is about 100 lb
lighter than the composite DA-20:

http://www.newplane.com/amd/spec.html
http://www.diamondair.com/contentc/c1spec.htm

--
Kevin Horton RV-8 (finishing kit) Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/ e-mail:
khorton02(_at_)rogers(_dot_)com


I don't disagree with you here at all. It is true that most composite
kitplanes and most composite factory-built aircraft are a little heavier
than similar aluminum aircraft. However, you will find that careful
layups like those in the lighter Longezes and Variezes, and indeed in
Rutan's Voyager, will produce an aircraft lighter and stronger than
aluminum. Matter of fact you can't really make a comparison because of
the
variations and the dissimilar advantages and disadvantages in each
method
of construction.

Let me ask you something. Do you believe an aircraft like the
around-the-world Voyager could have been constructed of aluminum? Has
anyone ever built an aluminum Quickie or Cozy or Velocity?

I'll give you another example --- Mike Arnold's 213 mph world champion
speedster, the AR-5. Do you believe that same airframe, which is very
light, btw, because of judicious (but not vacuum-bagged) layups, could
have been made of aluminum? I don't. The AR-5 defeated the previous
world record-holder, which was an aluminum BD-5. Aluminum and compound
curves don't mix. Aluminum and laminar flow airfoils don't mix either.
So I'd say that the composite aircraft 100 pounds heavier than the RV-6
is
faster on the same engine and prop combination. I may be wrong. At
least you can hide antennas inside the airframe.

Not taking anything away from 2024-T3, of course. Duralumin is still a
miracle material for aircraft construction. And, having recorded the
"From the Ground Up" series with Joe Schumacher and Mark Annick, I'm
envious of your RV-8 project.

I certainly agree that if your design needs very smooth exterior surfaces
or compound curves that you need to use some sort of composite.

And yes, the Voyager was a very light design. But was it really
fibreglas as you were originally talking about? I thought it had
graphite skins.

http://www.compositesengineering.com/Pages/Links.html

Some aluminum aircraft manage a good speed. Kent Paser made a long series
of incremental mods to his Mustang II and eventually had it doing 239 mph
at 8,000 ft on a 160 hp O-320. I wonder what the fastest fixed gear
Glasair does at 8,000 ft with an O-320.

So, lets agree - if you want the fastest speed, composite is probably
better. If you want the lightest weight, a review of similar
designs shows that aluminum usually wins.

--
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/
e-mail: khorton02(_at_)rogers(_dot_)com

Larry Smith wrote:

Aluminum and compound curves don't mix.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Bull****.

Just because most who homebuild have no English wheel, or shrinking hammer
skills, or that kit makers have not invested in the molds and dies to stamp
parts, does not mean that they can not be done. Do you mean that the
Mustang and Spitfire have no compound curves? Every one I have seen are
loaded with them.

Also, your comment that aluminum and laminar flows don't mix is equally full
of ****. Mustang was laminar flow, right?

As usual, you are in left field.
--
Jim in NC

"Morgans" wrote in message
...

Larry Smith wrote:

Aluminum and compound curves don't mix.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Bull****.

Just because most who homebuild have no English wheel, or shrinking hammer
skills, or that kit makers have not invested in the molds and dies to
stamp
parts, does not mean that they can not be done. Do you mean that the
Mustang and Spitfire have no compound curves? Every one I have seen are
loaded with them.

Also, your comment that aluminum and laminar flows don't mix is equally
full
of ****. Mustang was laminar flow, right?

No. It claimed to be but wasn't. When you sober up, read the research on
its failure to deliver true laminar flow. Rivet countersinking didn't do
the job and the skins were never true enough.

As usual, you are in left field.
--
Jim in NC

What is this guy building, other than an image as a morphine-addled kook?

Morgie, compound curves and aluminum don't mix because you have to have an
expensive press and molds to get them to. Maybe you have those. At least
in your opium dreams.

On Sat, 29 Nov 2003 21:00:54 -0500, Morgans wrote:


Larry Smith wrote:

Aluminum and compound curves don't mix.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Bull****.

Just because most who homebuild have no English wheel, or shrinking hammer
skills, or that kit makers have not invested in the molds and dies to
stamp parts, does not mean that they can not be done. Do you mean that
the Mustang and Spitfire have no compound curves? Every one I have seen
are loaded with them.

Also, your comment that aluminum and laminar flows don't mix is equally
full of ****. Mustang was laminar flow, right?

As usual, you are in left field.

Well, I hate to defend Larry, as I was on the other side of this arguement
from him, but I think you've gove a hit over the top here.

We were generally talking about homebuilt aircraft, and it is pretty rare
to find any aluminum ones with much in the way of compound curves. The
only kit that comes to mind was the Questair Venture - it performed well,
but didn't survive long in the market.

As far as the Mustang and laminar flow - yes it had a very early laminar
flow airfoil that worked well in the wind tunnel. But it was later
concluded that they didn't really get that much laminar flow in service
due to manufacturing imperfections, etc. See:

http://history.nasa.gov/SP-4305/ch4.htm

"...practical experience with this and other aircraft using advanced NACA
sections in the 1940s also showed that the airfoil did not perform quite
as spectacularly in flight as in the laboratory. Manufacturing tolerances
were off far enough, and maintenance of wing surfaces in the field
careless enough, that some significant points of aerodynamic similarity
between the operational airfoil and the accurate, highly polished, and
smooth model that had been tested in the controlled environment of the
wind tunnel were lost."

--
Kevin Horton RV-8 (finishing kit)
Ottawa, Canada
http://go.phpwebhosting.com/~khorton/rv8/
e-mail: khorton02(_at_)rogers(_dot_)com

Jim

There was a group (don't remember who, could have been NASA????)
sometime after the War who ran tests on the mustang wing and concluded
it was not laminar. Not sure now if this was from wind tunnel tests or
computer simulation? Also not sure what their object was, maybe just
too much time on their hands?

Do know that it paid off rather rapidly in a stall. Much faster than a
Clark Y type of airfoil. Also in cruise you would climb several
hundred feet above your cruise altitude and in a shallow descent back
to that altitude pick up 10 mph + which the bird would hold if you
were careful and held a constant attitude. Was told (bar talk) that
was a characteristic of a laminar flow wing????

Just more trivia for the grist mill.

Big John

On Sat, 29 Nov 2003 21:00:54 -0500, "Morgans"
wrote:


Larry Smith wrote:

Aluminum and compound curves don't mix.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Bull****.

Just because most who homebuild have no English wheel, or shrinking hammer
skills, or that kit makers have not invested in the molds and dies to stamp
parts, does not mean that they can not be done. Do you mean that the
Mustang and Spitfire have no compound curves? Every one I have seen are
loaded with them.

Also, your comment that aluminum and laminar flows don't mix is equally full
of ****. Mustang was laminar flow, right?

As usual, you are in left field.