Fiberglass vs. Fabric

Rich S. wrote:
"Lou" wrote in message
ps.com...

Well, maybe no sense right away, but the plans where drawn quite a
while ago. Like the Emeraude, the invention of fiberglass hadn't
arrived yet. Although I agree with the statement of making it as light
as possible, one of the reason's for this post is to discuss weight.
If this can be done with little or no weight penalty, then I thought I
would consider the experimental part of this group. After all, if Tony
Bingelis did it with good results, then why not consider it? I like the
idea of smoother, flatter, and more solid wings. If it turns out to be
25lbs or more, then I have to re-think this or just consider going on a
diet.


I understand where you're coming from, Lou - having had the same dilemma
myself while building the Emeraude. Fortunately we have a good builder
support group who could advise me on the nuances of that particular design.

Covering a wing with plywood that was originally designed for fabric and
open bays, will do more than change the appearance. An aircraft designer has
planned for the weight distribution (hence stress distribution) across the
span and chord. Skinning the wing will change both of those. You may
actually end up with a wing that is heavier, weaker and slower than before.
Do not make these design changes casually. Orville and Wilbur were
successful due to engineering, not trial and error.

First, ask yourself "What am I intending to accomplish by doing this?" Any
change requires more build time and usually more money. There can be other
penalties as well. If you're into engineering and test piloting as a hobby,
knock yourself out. It's your time, money and neck.

Re-engineering an older design can have no limit. Look at the fiberglass
version of the Beech 17 Staggerwing as an example. If you contemplate
changing a fabric wing to a skinned wing, why not go carbon fiber? How about
Nanotubes? Keep the end goal in sight.

Good Luck with your project!

Rich

P.S. The CAP-10C, the newest version of the Emeraude, now has a carbon fiber
spar.


Does it use that "pulltruded" carbon rod stuff for caps? That stuff is
incredibly strong, far superior to carbon roving in compression and tension.

John

Applying glass over ply skins results in a solid base for a
beautiful finish. Agree about the peel ply for sure.

The inside of the plywood should be sealed. Take a look at System
Three Clear Coat. Pure epoxy, water thin, first coat soaks in a lot.
Two coats does a nice job sealing plywood. Compatable with T-88 even
as a wet coat. In other words, you can paint the second layer of
ClearCoat on the ply skin, apply T-88 to rib caps, and bond
immediately. The other way is to squeege T-88 on to the ply. I guess
any epoxy might work as a sealer, but I like compatability at the rib
line bonds.

Dan Horton

"J.Kahn" wrote in message
... Rich

P.S. The CAP-10C, the newest version of the Emeraude, now has a carbon
fiber spar.
Does it use that "pulltruded" carbon rod stuff for caps? That stuff is
incredibly strong, far superior to carbon roving in compression and
tension.

I don't know. The website of Mudry Aviation has disappeared and I think the
company has been sold. I haven't had occasion to look it up.

Rich S.

Ok, everyone, I've started to experiment with fiberglass. I bought the
foam, the fabric,hardner and resin. I've mix the resin and hardener
with micro balloons and came up with something that resembles honey
dijon salad dressing. I've put it on the foam, layed down the fabric
and then had to mix more resin and hardener. Put that mix on top and
spread it around. Layed down another layer of fabric, mixed more
resin/hardener, spead it around and layed down dacron.
Now the big question, Does this sound correct? Can anyone tell me if
I missed a step? This so far is a test piece, but I know what I can use
it for. I am kinda suprised of how flexable the fiished product is.
Lou

On 25 Jun 2006 03:53:58 -0700, "Lou" wrote:

Ok, everyone, I've started to experiment with fiberglass. I bought the
foam, the fabric,hardner and resin. I've mix the resin and hardener
with micro balloons and came up with something that resembles honey
dijon salad dressing. I've put it on the foam, layed down the fabric
and then had to mix more resin and hardener. Put that mix on top and
spread it around. Layed down another layer of fabric, mixed more
resin/hardener, spead it around and layed down dacron.
Now the big question, Does this sound correct? Can anyone tell me if
I missed a step? This so far is a test piece, but I know what I can use
it for. I am kinda suprised of how flexable the fiished product is.
Lou

nah you've got it totally wrong :-)
y' dont Fiish the bloody stuff you squeegee it out thin.
pretend it's a million dollars a litre and make it extend as far as
possible.
remember "not white, not wet"

forget how flexible it is until it cures.
how heavy is it?

Stealth (glad it's him not me) Pilot

Lou wrote:
Ok, everyone, I've started to experiment with fiberglass. I bought the
foam, the fabric,hardner and resin. I've mix the resin and hardener
with micro balloons and came up with something that resembles honey
dijon salad dressing. I've put it on the foam, layed down the fabric
and then had to mix more resin and hardener. Put that mix on top and
spread it around. Layed down another layer of fabric, mixed more
resin/hardener, spead it around and layed down dacron.
Now the big question, Does this sound correct? Can anyone tell me if
I missed a step? This so far is a test piece, but I know what I can use
it for. I am kinda suprised of how flexable the fiished product is.
Lou


Put a layer of glass on the other side of the foam, then come back and
tell us how flexible it is.

Warning: Make d8mn sure you have the thing jigged to it's finished
position before the opposite side glass sets.

--
This is by far the hardest lesson about freedom. It goes against
instinct, and morality, to just sit back and watch people make
mistakes. We want to help them, which means control them and their
decisions, but in doing so we actually hurt them (and ourselves)."

On Tue, 27 Jun 2006 03:49:36 GMT, Ernest Christley
wrote:




Put a layer of glass on the other side of the foam, then come back and
tell us how flexible it is.

Warning: Make d8mn sure you have the thing jigged to it's finished
position before the opposite side glass sets.

I made a couple of test panels on 1/4" Clark foam using one layer of
heavier glass and one layer of model airplane glass on each side. You
could lay a 6" x 18" panel across two bricks and stand on it with out
much deflection. I figured it was good enough for a fuel tank, it has
held up for twenty years.

Thanks, I did layer up the other side and was quite suprised of the
stiffness. So far every piece will be flat, then cut to size and
glassed together, so it seems to be working out. Unfortunatley it's
been just under 70 deg. around here and especially in my basement so I
bought some 2 inch foam and a small heater. I made a make/shift oven to
help cure the fiberglass. I happen to have a remote thermometer inside
to watch the temp. It's been working out great.
Lou

Lou wrote:
Thanks, I did layer up the other side and was quite suprised of the
stiffness. So far every piece will be flat, then cut to size and
glassed together, so it seems to be working out. Unfortunatley it's
been just under 70 deg. around here and especially in my basement so I
bought some 2 inch foam and a small heater. I made a make/shift oven to
help cure the fiberglass. I happen to have a remote thermometer inside
to watch the temp. It's been working out great.
Lou


Do it again, Lou.
Hey, it's fun, right?

Slice off a few long 1x2's and glass each differently.

One layer of BID each side.
Two layers each side.
Three layers should do the trick.

Also try the same with UNI.
Like for building spar caps.
A single layer of BID on the long sides (the 2" sides)
and UNI on the top and bottom for capstrips...


Then try some deep compound curves!

There are a couple of articles on one-off cowling construction on my CD.
You can find it at:
http://www.matronics.com/photoshare/...et.03.04.2006/


Richard

Hey Caveman,
I tried your link but got nothing. Removed what I was supposed to and
still nothing.
Got Link?