Does it have to WHITE!!!

David Koehler wrote:
Greetings All,
I'm building a composite fuselage in South Texas, with out the aid of air
conditioning. Does anyone have some suggestions on getting the resin setup
time a little longer. I promote it for 85 degrees, I've tried a hotter
temperature but it doesn't set well. The temp in the garage is 95+. I've put
the resin container in a bucket of water and it helps a little.
I need to do a large piece and the only option I can see is scheduling
myself at 3am in the morning. It would be nicer if I could do it during the
day. Thanks for any help you guys can give.
david

How well is your garage insulated? I put some of the silver bubble
paper kind of insulation on the back of my garage door, that made a
big difference. Since I don't have an a/c vent in my garage, I put a
large fan in the doorway to the house to blow house air in there,
that also makes a big difference. I've thought of adding ceiling
insulation (in the garage attic) and blinds on the windows to help
some more.

Yellow is okay. I've felt the skin on yellow composites parked next to
white ones at airshows, and they feel about the same. On that same
day, a dark navy blue or black painted plane would burn your hand if
you touched it.

On Wed, 13 Jul 2005 08:25:00 -0500, "MJC" wrote:

Any really light, bright color should be fine, but white is definitely the
best for UV protection. Another question to ask yourself is if you'll be
keeping it in an enclosed hangar most of the time. If so, then it's almost a
non-issue.


From what I've gathered, it's not the UV protection, it is heat
absorption. Fiberglass composite gets "soft" when overheated, and
white and several other colours do not heat up as much as black, red,
and several other colours.

MJC

"Richard Riley" wrote in message
news
On Wed, 22 Jun 2005 20:34:32 -0400, "firstflight"
wrote:

:I have a composite kit aircraft, and it is time to paint! But I just
hate
:the idea of painting it WHITE (like most all the others). I understand
that
:HEAT is a big factor in this decision, and that white attracts the least
:amount of heat which could disrupt the Epoxy over time. Since my plane
is
:held together with Epoxy, this seems like a valid concern.
:
:What do you think people? Does it have to be white?? Could one choose a
:light yellow, light gray, silver,etc....... and not be pushing the
envelop
:too much?
:
:I happen to live in a very cool part of North America, so I am not too
:worried about regular heat (like someone in Arizona might be).

In Southern California I know of EZ's that are yellow, and Dick
Rutan's in Mojave is light blue. There's a beautiful Berkut in
England that's silver.

So, yes, it can be done if you are very, very careful. But do be VERY
VERY careful. Paint a sample panel, put it out at noon on one of the
hottest days of the year. Find out how hot it gets, check that
against the epoxy you're using AND the foam core - blue styrofoam
swells up when it gets too hot. It's not a cumulative problem - 4
years at 140 degrees won't do anything bad. 30 minutes at 200 degrees
and your airplane will be scrap.

Both are important, and both are long term, not short term problems.
What's significant is that the same thing you do to achieve protection of
one element (heat or UV) also, by happenstance, helps to protect from the
other element.
I have to say; if any composite resin gets "soft" when heated in direct
sun (no matter what color it's painted), I'd say that's a good reason to
never fly that aircraft again. A resin that gets soft in daytime sun is a
resin that was not properly cured (mixed wrong?) and is not airworthy in any
way and never will be. Makes me glad I'm building an RV :-)

MJC

wrote in message
...
On Wed, 13 Jul 2005 08:25:00 -0500, "MJC" wrote:

Any really light, bright color should be fine, but white is definitely
the
best for UV protection. Another question to ask yourself is if you'll be
keeping it in an enclosed hangar most of the time. If so, then it's
almost a
non-issue.


From what I've gathered, it's not the UV protection, it is heat
absorption. Fiberglass composite gets "soft" when overheated, and
white and several other colours do not heat up as much as black, red,
and several other colours.

MJC

I feel your comments are rather alarmist! Epoxies do soften if exposed the
heat higher than the cure temperature. How ever then this higher temperature
becomes the new softening temperature as the epoxy is now post cured.
There is a limit to this post curing but it is much higher than the sun can
generate.
--
Cy Galley
EAA Safety Programs Editor
Always looking for ideas and articles for EAA Sport Pilot
"MJC" wrote in message
...
Both are important, and both are long term, not short term problems.
What's significant is that the same thing you do to achieve protection of
one element (heat or UV) also, by happenstance, helps to protect from the
other element.
I have to say; if any composite resin gets "soft" when heated in direct
sun (no matter what color it's painted), I'd say that's a good reason to
never fly that aircraft again. A resin that gets soft in daytime sun is a
resin that was not properly cured (mixed wrong?) and is not airworthy in
any
way and never will be. Makes me glad I'm building an RV :-)

MJC

wrote in message
...
On Wed, 13 Jul 2005 08:25:00 -0500, "MJC" wrote:

Any really light, bright color should be fine, but white is definitely
the
best for UV protection. Another question to ask yourself is if you'll be
keeping it in an enclosed hangar most of the time. If so, then it's
almost a
non-issue.


From what I've gathered, it's not the UV protection, it is heat
absorption. Fiberglass composite gets "soft" when overheated, and
white and several other colours do not heat up as much as black, red,
and several other colours.

MJC

On Fri, 15 Jul 2005 07:53:36 -0500, "MJC" wrote:

Both are important, and both are long term, not short term problems.
What's significant is that the same thing you do to achieve protection of
one element (heat or UV) also, by happenstance, helps to protect from the
other element.
I have to say; if any composite resin gets "soft" when heated in direct
sun (no matter what color it's painted), I'd say that's a good reason to
never fly that aircraft again. A resin that gets soft in daytime sun is a
resin that was not properly cured (mixed wrong?) and is not airworthy in any
way and never will be. Makes me glad I'm building an RV :-)

MJC

"post curing" raises the softening temperature, but virtually all
common modern composites suffer some degree of softening at elevated
temps.

wrote in message
.. .
On Wed, 13 Jul 2005 08:25:00 -0500, "MJC" wrote:

Any really light, bright color should be fine, but white is definitely
the
best for UV protection. Another question to ask yourself is if you'll be
keeping it in an enclosed hangar most of the time. If so, then it's
almost a
non-issue.


From what I've gathered, it's not the UV protection, it is heat
absorption. Fiberglass composite gets "soft" when overheated, and
white and several other colours do not heat up as much as black, red,
and several other colours.

MJC

Yes it's vinyl ester resin, and regular glass lay-up. The first try was a
mixture for 90 degrees and it didn't harden. I mixed another batch for 85
degrees and it hardened like the big boys do. I only promote 600 cc's at a
time. We've had rather hot weather the past month, after 4 to 5 minutes I'm
jellin, and I'm not talking about shoe soles. I did put the resin in the
frig. and mix it cold, then do the glass, I had plenty of time and it looks
like it harden.
On the plus side, I read where it's advisable to have a heated room to cure
the glass lays.... Would you believe I have a heated garage, right now
anyway. Thank you for your time and consideration,
david

"......... :-))" wrote in message
u...
Would help if you told us what sort of resin ... sounds like a Vinyl Ester
if you are promoting it but which one and what are you promoting it with
and
in what quantities ? Are you vacuum bagging or is it just a conventional
wet layup ?


"David Koehler" wrote in message
...
Greetings All,
I'm building a composite fuselage in South Texas, with out the aid of
air
conditioning. Does anyone have some suggestions on getting the resin
setup
time a little longer. I promote it for 85 degrees, I've tried a hotter
temperature but it doesn't set well. The temp in the garage is 95+. I've
put
the resin container in a bucket of water and it helps a little.
I need to do a large piece and the only option I can see is scheduling
myself at 3am in the morning. It would be nicer if I could do it during
the
day. Thanks for any help you guys can give.
david

My garage is detached, and just a shell, no insulation. I've solved my
problem by doing what my eaa consular suggested, butting the resin in the
frig. and cooling it off. I got the large piece of glass on with time to
spare. He was concerned about groceries in the box, but the only thing I
have in the one in the garage is beer.... It doesn't look like it affected
the resin at all. Thanks to all for the help,
David

"Jim Carriere" wrote in message
...
David Koehler wrote:
Greetings All,
I'm building a composite fuselage in South Texas, with out the aid of
air
conditioning. Does anyone have some suggestions on getting the resin
setup
time a little longer. I promote it for 85 degrees, I've tried a hotter
temperature but it doesn't set well. The temp in the garage is 95+. I've
put
the resin container in a bucket of water and it helps a little.
I need to do a large piece and the only option I can see is scheduling
myself at 3am in the morning. It would be nicer if I could do it during
the
day. Thanks for any help you guys can give.
david

How well is your garage insulated? I put some of the silver bubble
paper kind of insulation on the back of my garage door, that made a
big difference. Since I don't have an a/c vent in my garage, I put a
large fan in the doorway to the house to blow house air in there,
that also makes a big difference. I've thought of adding ceiling
insulation (in the garage attic) and blinds on the windows to help
some more.

"David Koehler" wrote in message
...



snipped


He was concerned about groceries in the box, but the only thing I
have in the one in the garage is beer.... It doesn't look like it affected
the resin at all.

Have a couple beers and I bet it will affect the resin (and the rest of the
job) :-)

BarrenSands wrote:
"David Koehler" wrote in message
...



snipped


He was concerned about groceries in the box, but the only thing I
have in the one in the garage is beer.... It doesn't look like it affected
the resin at all.


Have a couple beers and I bet it will affect the resin (and the rest of the
job) :-)



Temps are also a little high here in North Carolina lately. I'm about
done welding. Just gotta be sure to clean the sweat off the steel, then
add a little oil. But what will sweat do to a layup?

--
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)."