Gelcoat repair

On Nov 18, 4:12*pm, Craig wrote:
On Nov 18, 3:35*pm, glider wrote:

*The process is very messy and can be hazardous to your health.
And it takes many, many hours of careful preperation.
*Labor intensive.
*As JJ said, mass balance of controls *is very important.
* 400-1000 hours is possible...no joke.
*Polyurethane may be best way to go.
*GA

Jim Phoenix nicely documented the refinish on his Nimbus 3.http://www.jimphoenix.com/?page_id=42

Heck, anything less than 18m will seem like a cakewalk. *Just don't
plan on having a social life this winter...

Best regards,
Craig Funston

Jim Phoenix reads RAS from time to time, so I'll try not to tell any
lies. I corresponded with him quite some time ago, about the time I
was re-finishing a small portion of my fuselage with gelcoat.
Regarding the gelcoat vs poly, I'm pretty sure he said if he had it
to do over again, he wouldn't gelcoat, he'd shoot polyurethane.

Heck, anything less than 18m will seem like a cakewalk. *Just don't
plan on having a social life this winter...

I am restoring an LS-1 right now. And I can truely attest to the
amount of work it's taking. I'm taking my time, going very slow and
using the advice from 6 mentors who have repainted a glider before.
One of which is giving me weekly advice, sometimes daily.

My friend Ralph Luebke who has built many gliders before gave me a
peice of a wing that came from a grob twin astir. I would HIGHLY
recommend getting a small peice from a wrecked glider and practing on
that first. This was a great idea that has taught me a bunch. I took
a 3 foot section about mid wing that was sawed off on both sides, then
aggresively took a sander to it to see just how it would look to go
through the gelcoat and into the fiberglass. You can destroy the
bottom side perhaps to learn by pushing the limits of a sander, or you
could take another section and restore it with "no fear" of hurting a
wing. It was great to purposely make a mistake on a wrecked gliders
wing verses accidently making mistake on an airworthy glider like my
LS-1.

If your retired, part time or on an airline pilot schedule like me (20
days off/month)...the amount of work can easily be scheduled as to
avoid interferring with your social life. I have really had alot of
fun in the garage listening to talk radio, listening to my ipod and
spending time on my favorite hobby during a rainy day. So far, it's
alot of work, but enjoyable to see this old glider come back to life!

Anybody got a wrecked fiberglass glider wing (1 to 3 foot section)
they could give to jeplane?

"Uncle Fuzzy" wrote

Jim Phoenix reads RAS from time to time, so I'll try not to tell any
lies. I corresponded with him quite some time ago, about the time I
was re-finishing a small portion of my fuselage with gelcoat.
Regarding the gelcoat vs poly, I'm pretty sure he said if he had it
to do over again, he wouldn't gelcoat, he'd shoot polyurethane.

Is that polly paint, or something else you are talking about? What polly
product builds as thick as jell coat?

I'm still trying to learn about the glass and more exotic composites. I'm a
wood or metal kinda' guy!
--
Jim in NC

On Nov 18, 9:17*pm, Uncle Fuzzy wrote:
On Nov 18, 4:12*pm, Craig wrote:





On Nov 18, 3:35*pm, glider wrote:

*The process is very messy and can be hazardous to your health.
And it takes many, many hours of careful preperation.
*Labor intensive.
*As JJ said, mass balance of controls *is very important.
* 400-1000 hours is possible...no joke.
*Polyurethane may be best way to go.
*GA

Jim Phoenix nicely documented the refinish on his Nimbus 3.http://www.jimphoenix.com/?page_id=42

Heck, anything less than 18m will seem like a cakewalk. *Just don't
plan on having a social life this winter...

Best regards,
Craig Funston

Jim Phoenix reads RAS from time to time, so I'll try not to tell any
lies. *I corresponded with him quite some time ago, about the time I
was re-finishing a small portion of my fuselage with gelcoat.
Regarding the gelcoat vs poly, *I'm pretty sure he said if he had it
to do over again, he wouldn't gelcoat, he'd shoot polyurethane.- Hide quoted text -

- Show quoted text -

I've refinished in both Acrylic Urethane and polyester topcoat
(commonly called "gelcoat'). From my experience, each has it's place.
Gelcoat goes on thick and is tolerant of a lot of sins. Amatuer
spraying skills don't make a disaster. It does get hard and takes
quite a bit of work to sand out and polish. Life expectancy, if done
right and stored properly, should be plenty long.
It is comparatively inexpensive- roughly $500 for a 15 meter glider
for material and catalyst.
AU- I use PPG Concept as suggested by JJ and others, requires
excellent preparation and as perfect a surface as you can get because
it does not have much thickness. Gloss is great and is sands easier
than gelcoat.
BUT. Time and effort, from my experience with both is that the extra
time in prep before spraying AU exceeds the difference to sand out and
polish gelcoat.
AU is outstanding in UV protection and far exceeds gelcoat with
respect to weathering.
AU costs about 2 1/2 times as much as gelcoat.
AU must be sprayed in a safer environment and MUST be done using full
positive pressure protection gear as it contains what is essentially a
nerve toxin(aliphatic isocyanate).
Gelcoat is easier for fixing up that occasional ding.
So- long winded- which to use and why.
We did our ASK-21's in AU because of amount of time in weather and
harder life.
We do others in gelcoat for easier touchup, lower cost , and less
toxic exposure.
If you are going to do one glider one time as a beginner, I would
suggest polyester finish.
JJ likes AU but remember he has a huge amount of experience that a new
person won't have. Choice may well also be affected by availability of
experienced help.
FWIW
UH

On Nov 19, 5:58*am, wrote:
On Nov 18, 9:17*pm, Uncle Fuzzy wrote:





On Nov 18, 4:12*pm, Craig wrote:

On Nov 18, 3:35*pm, glider wrote:

*The process is very messy and can be hazardous to your health.
And it takes many, many hours of careful preperation.
*Labor intensive.
*As JJ said, mass balance of controls *is very important.
* 400-1000 hours is possible...no joke.
*Polyurethane may be best way to go.
*GA

Jim Phoenix nicely documented the refinish on his Nimbus 3.http://www..jimphoenix.com/?page_id=42

Heck, anything less than 18m will seem like a cakewalk. *Just don't
plan on having a social life this winter...

Best regards,
Craig Funston

Jim Phoenix reads RAS from time to time, so I'll try not to tell any
lies. *I corresponded with him quite some time ago, about the time I
was re-finishing a small portion of my fuselage with gelcoat.
Regarding the gelcoat vs poly, *I'm pretty sure he said if he had it
to do over again, he wouldn't gelcoat, he'd shoot polyurethane.- Hide quoted text -

- Show quoted text -

I've refinished in both Acrylic Urethane and polyester topcoat
(commonly called "gelcoat'). From my experience, each has it's place.
Gelcoat goes on thick and is tolerant of a lot of sins. Amatuer
spraying skills don't make a disaster. It does get hard and takes
quite a bit of work to sand out and polish. Life expectancy, if done
right and stored properly, should be plenty long.
It is comparatively inexpensive- roughly $500 for a 15 meter glider
for material and catalyst.
AU- I use PPG Concept as suggested by JJ and others, requires
excellent preparation and as perfect a surface as you can get because
it does not have much thickness. Gloss is great and is sands easier
than gelcoat.
BUT. Time and effort, from my experience with both is that the extra
time in prep before spraying AU exceeds the difference to sand out and
polish gelcoat.
AU is outstanding in UV protection and far exceeds gelcoat with
respect to weathering.
AU costs about 2 1/2 times as much as gelcoat.
AU must be sprayed in a safer environment and MUST be done using full
positive pressure protection gear as it contains what is essentially a
nerve toxin(aliphatic isocyanate).
Gelcoat is easier for fixing up that occasional ding.
So- long winded- which to use and why.
We did our ASK-21's in AU because of amount of time in weather and
harder life.
We do others in gelcoat for easier touchup, lower cost , and less
toxic exposure.
If you are going to do one glider one time as a beginner, I would
suggest polyester finish.
JJ likes AU but remember he has a huge amount of experience that a new
person won't have. Choice may well also be affected by availability of
experienced help.
FWIW
UH

UH,

I am guessing the "gelcoat" is Prestec, made by Simtec Coatings? I
sprayed my Apis with it. I do like using it also. The guys at Simtec
will tell you they call it a "polyester topcoat".

The one nagging problem I can't seem to get away from is that here in
the Pacific NW, my Apis grows nasty blisters in the paint every year
around this time. I have a well insulated trailer, with a vent. But, I
am not able to run power to the trailer for a heat source and a small
fan.

Cheers,
Brad

Jim Phoenix reads RAS from time to time, so I'll try not to tell
any
lies. *I corresponded with him quite some time ago, about the time I
was re-finishing a small portion of my fuselage with gelcoat.
Regarding the gelcoat vs poly, *I'm pretty sure he said if he had it
to do over again, he wouldn't gelcoat, he'd shoot polyurethane.- Hide quoted text -


Yup, I still believe that. Gelcoat is very forgiving for the amateur
(like me), but I was shocked at how much weight it adds, and when done
poorly, you can add a lot of weight covering up bad spray jobs. Flight
controls expecially get heavy with gelcoat and I ended up shooting the
elevators on the Nmbus with polyurethane because I couldn't get them
mass balanced within limits - very frustrating. If I had to do it
again, I would do the gelcoat removal and sanding and profiling and
priming myself then have a pro shoot on the polyurethane. Polyurethane
is dangerous if not applied in a proper envirnment due to it's
hazards.

With regard to Bob K.s reading of part 43, he's right - almost... 43.1
applicability reads "This part does not apply to any aircraft for
which the FAA has issued an experimental certificate, unless (here's
the fun part) the FAA has issued a different kind of certificate for
that aircraft [Amend #39, eff. 01 SEP 2004].

So what that means is that if your glider was a TC'd model with a
standard airworthiness issued and you somehow got an experimental
certificate for it later, well then part 43 does apply to you. Sounds
kinda crazy I know, but it's happened in the GA world - but is much
more prevalent in the air carrier world when STC developers need to
take a TC'd aircraft and put it into experimental R&D or some such
thing while they perform test flights to satisfy the FAA, then the
aircraft goes back to Standard Airworthiness after the test flights
are done and the STC is approved - bottom line is that 43 continues to
apply throughout the experimental life of the project. Too much info
probably, but hey there ya go.

Jim

Oh, yeah also I'm an A&P and was an IA at the time so I could do all
that work myself, the average glider pilot would need to work under
the supervision of an A&P and have it signed off appropriately,
depending (as Bob and Hank have said) on your airworthiness
certificate or ops limitations requirements - seems they are all
different.

Jim

On Nov 19, 9:34*am, Nimbob wrote:

...With regard to Bob K.s reading of part 43, he's right - almost... 43.1
applicability reads "This part does not apply to any aircraft for
which the FAA has issued an experimental certificate, unless (here's
the fun part) the FAA has issued a different kind of certificate for
that aircraft [Amend #39, eff. 01 SEP 2004].

So what that means is that if your glider was a TC'd model with a
standard airworthiness issued and you somehow got an experimental
certificate for it later, well then part 43 does apply to you...

Jim, please help me be sure I understand this:

The way I read the text of 43.1, it states that part 43 does or does
not apply to a certain aircraft depending on the type of airworthiness
certificate issued for _that particular aircraft_.

But the way you are describing your interpretation, you seem to be
saying that 43.1 says that part 43 applies or does not apply to _all
aircraft of a particular type_ depending on whether or not the
manufacturer has obtained type certification for that aircraft type.
Do I understand your interpretation correctly?

This issue is of particular importance for owners of sailplanes where
some units imported into the US were certified as experimental,
racing, and for which a standard airworthiness certificate was never
issued, but for which the factory has obtained type certification for
that model.

Thanks, Bob K.

Anybody ever use PolyLux?

It's what George Applebay uses on all of his aircraft. It can be
sprayed through a regular spray gun. SimTec has to be shot through a
much more expensive spray gun. Also, PolyLux is much cheaper.

On Nov 19, 12:46*pm, Scott Alexander
wrote:
Anybody ever use PolyLux?

It's what George Applebay uses on all of his aircraft. *It can be
sprayed through a regular spray gun. *SimTec has to be shot through a
much more expensive spray gun. *Also, PolyLux is much cheaper.

I've sprayed Prestec successfully using a Laquer gun, and also a HVLP
conversion gun. 1.8mm tip and thinned per specs with Acetone.

That being said, only rarely do I get a non-orange peel finish, but
the stuff cuts easily if you get to it within a day of setting.

Brad