Scratch removal advice needed

A week ago, I and my crew spent a fair part of day giving my glider a nice wax job. So, of course, 5 days later I landed out in a nice, freshly plowed corn field.

The landing went fine but, unfortunately, due to an uneven surface and excessive braking, I put AG up on her nose a couple of times.

The resulting scratches under the nose seem to be in, not through, the polyurethane paint. There does seem to be some dirt embedded in the scratches that won't come out with soap and water.

I would welcome suggestions on what type of rubbing compound or correcting cream people with similar experiences have used to successfully remove the scratches.

Thanks in advance!

Lou
LAK17at "AG"

On Sunday, May 21, 2017 at 10:29:42 AM UTC-4, MNLou wrote:
A week ago, I and my crew spent a fair part of day giving my glider a nice wax job. So, of course, 5 days later I landed out in a nice, freshly plowed corn field.

The landing went fine but, unfortunately, due to an uneven surface and excessive braking, I put AG up on her nose a couple of times.

The resulting scratches under the nose seem to be in, not through, the polyurethane paint. There does seem to be some dirt embedded in the scratches that won't come out with soap and water.

I would welcome suggestions on what type of rubbing compound or correcting cream people with similar experiences have used to successfully remove the scratches.

Thanks in advance!

Lou
LAK17at "AG"

Take "AG" to a small auto body shop. If you can't wash out the dirt it means it is a darker primer and you need to sand and paint. Talk to a small auto body shop. Preferably one man outfit. Someone who is willing to tinker with things. Best would be a custom motorcycle paint shop. Most of these guys are great with lots of attention to details. Don't try to fix it yourself. The paints are not designed to be handled by non-professionals as good protection equipment is required.

On Sunday, May 21, 2017 at 7:29:42 AM UTC-7, MNLou wrote:
A week ago, I and my crew spent a fair part of day giving my glider a nice wax job. So, of course, 5 days later I landed out in a nice, freshly plowed corn field.

The landing went fine but, unfortunately, due to an uneven surface and excessive braking, I put AG up on her nose a couple of times.

The resulting scratches under the nose seem to be in, not through, the polyurethane paint. There does seem to be some dirt embedded in the scratches that won't come out with soap and water.

I would welcome suggestions on what type of rubbing compound or correcting cream people with similar experiences have used to successfully remove the scratches.

Thanks in advance!

Lou
LAK17at "AG"

Try using Meguiar's rubbing, then polishing compound:

https://www.youtube.com/watch?v=byRA0lCXpzg

Tom

On 5/21/2017 8:29 AM, MNLou wrote:
A week ago, I and my crew spent a fair part of day giving my glider a nice
wax job. So, of course, 5 days later I landed out in a nice, freshly
plowed corn field.

The landing went fine but, unfortunately, due to an uneven surface and
excessive braking, I put AG up on her nose a couple of times.

Sorry about the nose rubbing; welcome to a large club! I apologize in advance
for the (minor?) thread drift, but prevention is arguably a form of
amelioration ( ), so just in case this hasn't post-scrape already occurred
to you...

After my first dirt-rub in a plowed/smoothed field (my favored off-field
choice), I modified my braking technique to not use any until after getting a
roll-out feel for how much braking the field itself provided. With that known,
no more brake than just enough to where the tail lightens until the plane
stops (usually ~150 paced-off-feet for 15-meter glass; ~180 paced-off-feet for
a G-103 w. 2 aboard). Rationale: the arguably increased risk from a (very
slightly) longer roll-out is essentially nil since such fields are about as
guaranteed hole/big-rock free as anything short of a paved runway. No more
dirt-rubbing of the ship's nose...

YMMV,
Bob W.

On Sunday, May 21, 2017 at 7:14:44 PM UTC-7, BobW wrote:
On 5/21/2017 8:29 AM, MNLou wrote:
A week ago, I and my crew spent a fair part of day giving my glider a nice
wax job. So, of course, 5 days later I landed out in a nice, freshly
plowed corn field.

The landing went fine but, unfortunately, due to an uneven surface and
excessive braking, I put AG up on her nose a couple of times.

Sorry about the nose rubbing; welcome to a large club! I apologize in advance
for the (minor?) thread drift, but prevention is arguably a form of
amelioration ( ), so just in case this hasn't post-scrape already occurred
to you...

After my first dirt-rub in a plowed/smoothed field (my favored off-field
choice), I modified my braking technique to not use any until after getting a
roll-out feel for how much braking the field itself provided. With that known,
no more brake than just enough to where the tail lightens until the plane
stops (usually ~150 paced-off-feet for 15-meter glass; ~180 paced-off-feet for
a G-103 w. 2 aboard). Rationale: the arguably increased risk from a (very
slightly) longer roll-out is essentially nil since such fields are about as
guaranteed hole/big-rock free as anything short of a paved runway. No more
dirt-rubbing of the ship's nose...

YMMV,
Bob W.

I have NEVER had to use any wheel brake in a plowed field - I was stopped long before I even THOUGHT about using it.

Tom

On 21/05/2017 16:29, MNLou wrote:

The resulting scratches under the nose seem to be in, not through, the polyurethane paint. There does seem to be some dirt embedded in the scratches that won't come out with soap and water.

I would welcome suggestions on what type of rubbing compound or correcting cream people with similar experiences have used to successfully remove the scratches.

I have owned and flown gliders with PU paint for many years and I would
never consider a refinishing a glider with gel coat. (Actually once you
have a decent PU paint job, you wont ever need to refinish it).

But PU has its weaknesses. The colour layer is very thin. If the
scratches penetrate the paint you cannot polish them out, you have to do
a touch up.

My approach to this:

Wash, then polish as best you can, then leave the scratches till the end
of the season. I normally accumulate scratches for two or three seasons
before touching them all up.


For an "airfield" repair. This is not a 100% invisible repair like a
professional job but it can still be pretty neat and you can DIY over a
weekend or two:

- Sand out scratches completely.
- Clean area with acetone to remove all traces of polish etc (or you
will get "brown stains").
- Brush on several thick layers of 2 part PU primer (You can mix up a
batch of 2 part primer and it will have a pot life of a few hours. But
once it is painted on the glider, it will harden within say an hour.
Thus you can use one mix to apply 2 or 3 coats to build up the thickness
without it running). It must be thick enough to allow final finishing in
one step, or you waste another day.
- Allow the primer to dry completely ( 24 hours). This is at least a
two day procedure.
- Sand carefully to restore contour and a smooth finish.
- Touch up the colour with two or three coats from a spray can. Thin
coats, do not let it run. Mask surrounding areas to protect them from
over-spray. Masking before is quicker than cleaning up afterwards. I see
you can now get PU touch up spray but I have never tried it, maybe next
time. Otherwise hardware store "fridge white" normally works.
- Finish with very light 800 to 1500 grit wet sanding, then polish. Be
very careful that you do not go through the top colour layer.


For a "workshop" repair:

- Do the same as above. But use a spray gun and matching PU paint
instead of the spray can for the final layer.


There is some skill required in the above. But if you own the glider it
is one worth learning. Each season you will get better and learn new
tricks. Alternately get a contractor with sailplane experience to touch
it up every few years.


Ian