Paint "chipping" on leading edge of wings

[Stetson20]

Hi all,

The paint on my plane is older. Not ready to have it repainted yet. I have some minor chipping on the leading edge of the wings. It could possibly be an entry point for corrosion. Any thoughts or suggestions? I now park the plane on the ramp at KHEG in Jacksonville so it's more of a concern in the humid, salty air environment.

TIA

Stetson20

[EricJ]

47 minutes ago, Stetson20 said:

Hi all,

The paint on my plane is older. Not ready to have it repainted yet. I have some minor chipping on the leading edge of the wings. It could possibly be an entry point for corrosion. Any thoughts or suggestions? I now park the plane on the ramp at KHEG in Jacksonville so it's more of a concern in the humid, salty air environment.

TIA

Stetson20

Most auto parts stores sell touch-up pens and sticks and similar touch-up gear in wide varieties of colors.    I've had reasonable luck getting a close match (using an inspection plate or something), and just touching up with those.   They're not expensive and are reasonably easy to use.

https://www.oreillyauto.com/detail/c/scratch-fix-all-in-1/paint---body/paint/touch-up-paint/e3a53676b2d3/dupli-color-scratch-fix-all-in-1-0-5-ounce-bright-white-touch-up-paint/dpli/acc0362?q=touch-up+paint&pos=0

[Fly Boomer]

1 hour ago, Stetson20 said:

Hi all,

The paint on my plane is older. Not ready to have it repainted yet. I have some minor chipping on the leading edge of the wings. It could possibly be an entry point for corrosion. Any thoughts or suggestions? I now park the plane on the ramp at KHEG in Jacksonville so it's more of a concern in the humid, salty air environment.

TIA

Stetson20

Find the top automotive paint store.  They can match color from an inspection cover (don't use one from the bottom of the wing or horizontal) and put it in a rattle can for you.  No matter how faded your color, it will match.  There is a lot more to it, but starting with the correct color helps.

[PT20J]

How you fix this depends on how picky you are. The way the pros do it is get some paint to match and then take a very fine tipped artist brush and carefully fill in the chip with primer and then with paint being careful to not paint outside the edge of the chip. Then buff it out when the paint has cured. It's pretty tedious, but if done correctly, the result will be nearly impossible to detect. There are videos on Youtube.

Getting a good color match is the first step, but you will need to decide what kind of paint to use. Enamel is the easiest, but since the chips are on the leading edges you might want tougher paint in which case you would get a 2K polyurethane. This paint is mixed with a catalyst and dries very hard. It is the type of paint originally used on the airplane and on modern automobiles. Once mixed it has a working time or several hours, so you only mix a small amount at a time. 

[Fly Boomer]

4 hours ago, Stetson20 said:

Hi all,

The paint on my plane is older. Not ready to have it repainted yet. I have some minor chipping on the leading edge of the wings. It could possibly be an entry point for corrosion. Any thoughts or suggestions? I now park the plane on the ramp at KHEG in Jacksonville so it's more of a concern in the humid, salty air environment.

TIA

Stetson20

The tool Skip @PT20J is referring to may be like this one:

https://www.amazon.com/KINGART-920-Fine-Painting-Pen-5MM/dp/B07F6M1XBB/ref=sr_1_5_pp?crid=2XACORYFTB908&keywords=paint%2Bpen&qid=1693414473&sprefix=paint%2Bpen%2Caps%2C177&sr=8-5&th=1

[Fly Boomer]

2 hours ago, PT20J said:

Enamel is the easiest, but since the chips are on the leading edges you might want tougher paint in which case you would get a 2K polyurethane.

@Stetson20 I'm not aware of a color match capability yet, but you can now get a 2k primer in a rattle can from Eastwood.  Google it.

[N201MKTurbo]

7 minutes ago, Fly Boomer said:

@Stetson20 I'm not aware of a color match capability yet, but you can now get a 2k primer in a rattle can from Eastwood.  Google it.

I think the primer in a can has a button on the bottom to release the catalyst into the can. Then you shake it up and spray it. Not a good choice for small repairs, because once you activate the can you are committed to using the whole can within an hour or two.

[PT20J]

Any auto paint store should be able to color match and put polyurethane in 2K rattle cans. The cans hold 4 oz of paint and the catalyst is in the can released by punching a button on the bottom as @N201MKTurbo says. Once punched, the can is good for about a day before it hardens. (2K means two component, i.e., paint + catalyst. I believe the K is for komponente which is component in German). Don't confuse that with 2 stage paint which means basecoat + clearcoat more commonly used on autos.

But, you only want the cans if you are going to paint an area. There are three ways to paint an area that I am aware of. 1) paint an entire panel if possible. 2) Mask it off so that the paint line just looks like another panel line. 3) Blend the new and old paint at the paint line mechanically (sanding and rubbing compound). Some people here have done the latter and posted pictures. It's a lot of work. I talked to a couple of paint shops and they don't do it because the polyurethanes have a minimum specified film thickness and they tell me that the blended edge will deteriorate and become visible over time. How long, I have no idea.

Skip

 

[PT20J]

2 hours ago, Fly Boomer said:

The tool Skip @PT20J is referring to may be like this one:

https://www.amazon.com/KINGART-920-Fine-Painting-Pen-5MM/dp/B07F6M1XBB/ref=sr_1_5_pp?crid=2XACORYFTB908&keywords=paint%2Bpen&qid=1693414473&sprefix=paint%2Bpen%2Caps%2C177&sr=8-5&th=1

I meant these:

[N201MKTurbo]

15 minutes ago, PT20J said:

I meant these:

That pen think might be cool. I’ll have to try it next time I’m painting.

[Pinecone]

I watched the pros at the BMW factory in Greenville do paint chip repair.

They use the very small artist's brush.  They typically did not use primer.  But the trick is filling the chip without getting ANY paint outside the chip.

I haven't seen it done, but was told by a painter he uses a syringe to fill the chip.

[Stetson20]

The leading edge of the wings are painted black and I've had more than one person ask me why. It *looks* like deice boots, but it's just painted on. Maybe the reason is now becoming self-evident- only the leading edge need be repainted vs the entire wing. 

Thanks for all the tips!

 

 

[aviatoreb]

On 8/30/2023 at 9:56 AM, Stetson20 said:

Hi all,

The paint on my plane is older. Not ready to have it repainted yet. I have some minor chipping on the leading edge of the wings. It could possibly be an entry point for corrosion. Any thoughts or suggestions? I now park the plane on the ramp at KHEG in Jacksonville so it's more of a concern in the humid, salty air environment.

TIA

Stetson20

Well one very expensive solution for paint chipping on leading edges - put a titanium shield there - that's a side benefit of TKS is there is no chipping paint issue.

[Pinecone]

5 hours ago, Stetson20 said:

The leading edge of the wings are painted black and I've had more than one person ask me why. It *looks* like deice boots, but it's just painted on. Maybe the reason is now becoming self-evident- only the leading edge need be repainted vs the entire wing. 

Thanks for all the tips!

 

It also means you can see if you start getting ice.  And if you can get to sunlight, it will melt the ice quicker.

[Schllc]

On 8/30/2023 at 12:01 PM, PT20J said:

How you fix this depends on how picky you are. The way the pros do it is get some paint to match and then take a very fine tipped artist brush and carefully fill in the chip with primer and then with paint being careful to not paint outside the edge of the chip. Then buff it out when the paint has cured. It's pretty tedious, but if done correctly, the result will be nearly impossible to detect. There are videos on Youtube.

Getting a good color match is the first step, but you will need to decide what kind of paint to use. Enamel is the easiest, but since the chips are on the leading edges you might want tougher paint in which case you would get a 2K polyurethane. This paint is mixed with a catalyst and dries very hard. It is the type of paint originally used on the airplane and on modern automobiles. Once mixed it has a working time or several hours, so you only mix a small amount at a time. 

You can actually have the 2part paint put into a rattle can as well.  
the catalyst is stored separately in the can so you can mix immediately prior to use.  
you can get all of this done for under 100 per can.
Ask some of the auto body shops which store does this, because they don’t all do it but it’s awesome and incredibly reasonable for what you get. 

[Pinecone]

13 hours ago, Schllc said:

You can actually have the 2part paint put into a rattle can as well.  
the catalyst is stored separately in the can so you can mix immediately prior to use.  
you can get all of this done for under 100 per can.
Ask some of the auto body shops which store does this, because they don’t all do it but it’s awesome and incredibly reasonable for what you get. 

Yes, but it is one shot.  You mix it and you have to use it within the pot life (which is not the amount of time it stays liquid.  After that time period, you toss the can.

If you get a small can with a small can of catalyst and some also need an activator, you can mix up a small amount as needed.

[Schllc]

2 hours ago, Pinecone said:

Yes, but it is one shot.  You mix it and you have to use it within the pot life (which is not the amount of time it stays liquid.  After that time period, you toss the can.

If you get a small can with a small can of catalyst and some also need an activator, you can mix up a small amount as needed.

True, my reasoning is that mixing two part paint is not a beginner activity, but when the ratios and mixing are done by a professional the outcome is usually better.  I did this with a repair some years ago and was amazed at how well it matched, flowed and blended.  Having the touchup to mix in perpetuity works too, just think that brushing touchups is almost impossible to blend.  Either way protects the aluminum, and I just didn't have a problem getting a can each time it was needed.

 

[PT20J]

You can really get both. The smallest amount of paint that a paint store will custom mix is usually a pint which is 16 oz. A rattle can holds 4 oz. So you can have them fill three cans and still have around 4 oz left over.

Mixing components is trivial if you can measure. You should only need reducer if you are going to spray it.

Be very careful if you spray polyurethane. Overspray mist will stick to whatever it touches and dry hard as epoxy. You really need to mask everything. 

[Pinecone]

8 hours ago, Schllc said:

True, my reasoning is that mixing two part paint is not a beginner activity, but when the ratios and mixing are done by a professional the outcome is usually better.  I did this with a repair some years ago and was amazed at how well it matched, flowed and blended.  Having the touchup to mix in perpetuity works too, just think that brushing touchups is almost impossible to blend.  Either way protects the aluminum, and I just didn't have a problem getting a can each time it was needed.

But the point is, you have a $100 rattle can, you mix it, and hour later it is trash.  If you are not done, you have to get another one.

Brush touchups can be virtually invisible.  As mentioned, you need a VERY fine tip artist brush and only fill the chip.  The problem with blending comes from sloppy paint onto the adjacent paint making a bump.

[MikeOH]

Well, if I was worried about 'wasting' part of a $100 4 ounce can of matched paint then I wouldn't even own an aircraft!

I guess I'm just not a real CB, after all

But, the expense and hassle of buying 16 oz of paint and catalyst, fine tip brushes, mixing a small amount properly (I don't own a gram scale) and having the skill to pull off filling just the chip out (I have some experience trying this with cars; it is NOT an easy skill to acquire!)....$100 is a bargain if I can take care of the leading edges of my wings.  Frankly, I'm concerned that 4 ounces may not be enough!

[Pinecone]

If you are going to spray the leading edge, the rattle can works well.

But when you spray the leading edge, you will still see the chips, but they will covered at least.

Unless you sand the leading edge and feather the chips.

And yes, 4 ounces will not do it.

BTW, a gram scale costs about $10 - https://www.amazon.com/Weigh-Gram-Digital-Jewelry-Kitchen/dp/B06Y61YW7S/ref=sr_1_1_sspa?crid=C6F144G5R5ON&keywords=gram+scale&qid=1693618043&sprefix=gram+scale%2Caps%2C107&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

 

[MikeOH]

Yuup, sand/feather and spray is my plan.  There will likely be a masking line somewhere, but it will look a heck of a lot better than it does now!  You can see the missing paint from 100 feet away; if someone has to move up to 12" to see the mask line I'll consider it a success!

Ya got me on the scale!  10 bucks!  Never would have imagined that; you'd think the bowl of rice the Chinese worker was paid and shipping would have been more than that!

I wonder if it can tell 1 gram from 1 kilogram?