Fine scratches on wing gel coat

Jack wrote:
Tim Mara wrote:
absolutely NOT........RainX causes rain to form tiny droplets which are then
blown off by wind......you want no droplets at all...ever..
tim

"Jack" wrote in message
et...
Bob Caldwell wrote:
The bigger issue is with flying in rain. The highly polished, waxed
finish will bead up with water droplets. The rougher surface will
shed water without forming the really draggy (is that a word?)
droplets. Same as if you waxed your windshield in your car, water
beads up instead of sheeting off. So if and when you have to blast
through that virga line the drop in performance will not be as
severe.
So, should we be using RainEx on our wings?


But many do wax the wings -- and so get BIG drops -- do they not.

Is the only answer to stay out of the rain and/or simply clean your
wings with pure water, but never apply any protective finish?


Jack

Re Wax- Some airfoils don't want to be polished and waxed. The Wortman
FX 67-150/170 series is an example of this. These like a little(400grit
at 45 degrees) roughness. When my PIK climb started to drop off, I'd
give it a bit of a scuff. I washed with dish soap and wiped dry
without a lot of rinsing. Soap wetted out rain and it tolarated rain
much better. Otherwise, when the rain drop hits the canopy- put the
gear down.
hard to keep looking nice when doing this though.
UH

wrote:

Re Wax- Some airfoils don't want to be polished and waxed. The Wortman
FX 67-150/170 series is an example of this. These like a little(400grit
at 45 degrees) roughness. When my PIK climb started to drop off, I'd
give it a bit of a scuff. I washed with dish soap and wiped dry
without a lot of rinsing. Soap wetted out rain and it tolarated rain
much better. Otherwise, when the rain drop hits the canopy- put the
gear down.
hard to keep looking nice when doing this though.

And it might be hard to preserve them, too, unless they are painted like
the PIK's wings (urethane?). Gel coat on wings lasts longer when it's
kept waxed. I haven't heard that periodic light sanding protects the gel
coat against cracking, but I haven't heard of any testing done, either.

--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Hank's experience echoes mine. I kept my LS-3 (same airfoil as PIK-20B;
also Mosquito, Nimbus 2, etc.) at 400 grit most of the time and it did
seem to make a difference in the rain. Keeping it clean was no problem.
Water worked for most things. And for stubborn bugs, just sand them
off.

Chip Bearden
ASW 24 "JB"

wrote:
Hank's experience echoes mine. I kept my LS-3 (same airfoil as PIK-20B;
also Mosquito, Nimbus 2, etc.) at 400 grit most of the time and it did
seem to make a difference in the rain. Keeping it clean was no problem.
Water worked for most things. And for stubborn bugs, just sand them
off.

Cheez, all this talk about rain. Chip, you need to come out West and fly
in the sun! It's more fun, and it eliminates sanding time. Waxing time
might increase, but you are rewarded with a shiny glider.

And one more thing: if you do fly in the rain out West, that's because
there is good lift there. Saved myself quite a few times by thermalling
on the edge of a rain shaft.


--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org