PU finish in wave flying

My Stemme, finished in PU and 16 years old still has a perfect finish
except for chips and scratches.Â* I fly in wave quite often.

On 1/29/2020 9:24 AM, wrote:
On Wednesday, January 29, 2020 at 11:16:57 AM UTC-5, Eric wrote:
Can anyone tell from experience how well a PU finish holds when flying in wave conditions, i.e. low temperatures & strong turbulence?
I'm considering to repaint my glider, remove old gelcoat apply T35 as filler polyurethane on top. Can I go wave-flying again with peace of mind? To what extent is a PU finish vulnerable to cracking due to change in temperature? There's tons of information on the refinish topic, but I couldn't find the answer to this particular question.

Thanks!
T35 is polyester "gelcoat". That is the stuff that cracks. I would remove all "gelcoat", fill and surface with thin layer of polyester spray filler, then paint in UU/PU.
Good luck
UH

--
Dan, 5J

Dan Marotta wrote on 1/29/2020 9:28 AM:
On 1/29/2020 9:24 AM, wrote:
On Wednesday, January 29, 2020 at 11:16:57 AM UTC-5, Eric wrote:
Can anyone tell from experience how well a PU finish holds when flying in wave
conditions, i.e. low temperatures & strong turbulence?
I'm considering to repaint my glider, remove old gelcoat apply T35 as filler
polyurethane on top. Can I go wave-flying again with peace of mind? To what
extent is a PU finish vulnerable to cracking due to change in temperature?
There's tons of information on the refinish topic, but I couldn't find the
answer to this particular question.

Thanks!
T35 is polyester "gelcoat". That is the stuff that cracks. I would remove all
"gelcoat", fill and surface with thin layer of polyester spray filler, then
paint in UU/PU.
Good luck
UH

My Stemme, finished in PU and 16 years old still has a perfect finish except for

chips and scratches. I fly in wave quite often.

It's not the wave flying that does it, of course, but the low temperatures. What
OAT do you typically see while wave flying, and what is the lowest OAT you've seen
while flying the Stemme?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1

Single digits, say 5 deg F.

On 1/29/2020 10:46 AM, Eric Greenwell wrote:
Dan Marotta wrote on 1/29/2020 9:28 AM:
On 1/29/2020 9:24 AM, wrote:
On Wednesday, January 29, 2020 at 11:16:57 AM UTC-5, Eric wrote:
Can anyone tell from experience how well a PU finish holds when
flying in wave conditions, i.e. low temperatures & strong turbulence?
I'm considering to repaint my glider, remove old gelcoat apply
T35 as filler polyurethane on top. Can I go wave-flying again
with peace of mind? To what extent is a PU finish vulnerable to
cracking due to change in temperature? There's tons of information
on the refinish topic, but I couldn't find the answer to this
particular question.

Thanks!
T35 is polyester "gelcoat". That is the stuff that cracks. I would
remove all "gelcoat", fill and surface with thin layer of polyester
spray filler, then paint in UU/PU.
Good luck
UH

My Stemme, finished in PU and 16 years old still has a perfect
finish except for

chips and scratches.Â* I fly in wave quite often.

It's not the wave flying that does it, of course, but the low
temperatures. What OAT do you typically see while wave flying, and
what is the lowest OAT you've seen while flying the Stemme?


--
Dan, 5J