Paint touchup technique and materials?

Artimas

Pre-takeoff checklist
Joined
Dec 10, 2013
Messages
214
Location
New Jersey
Display Name

Display name:
Artimas
The plane will be down for the next 6 weeks while I wait for a new engine so I thought I'd fix up a couple of things. One is paint.

Overall the paint is in good shape but there is one area near the windshield and one on the cowling where an area about 1" wide is peeling away. The paint is thick and brittle. To feather it in, it looks like I would have to fill in some thickness after peeling way the paint that is lifted up. What's the best way to fix that?

Also,there is a tiny area on the leading edge of the horizontal stabilizer where the paint is slightly bubbled. I suspect there may be some slight corrosion starting underneath. I want to "sand" it down to bare metal, clean it up, prime and paint it with an airbrush. What are the proper materials to use? The existing paint is Imron.

Thanks in advance.
 
i dont mean to sound harsh, but if you do not know how to properly prep for paint, that includes feather sanding to existing paint, don't do it. get someone that knows what they are doing. imron has some nasty chemicals in it and the proper safety gear must be used. i know guys that will not shoot it without a forced air system. also, there is a proper procedure to prep aluminum otherwise the paint will not stick. at least get a painter to work you through it.

bob
 
Your going to have a hard time trying to match ,the existing paint,to your patches. Good luck ,let us now how it works out.
 
In some respects this no different that auto painting.....feather the damaged areas without sanding rivets....then mask "everything", taping and covering "everything" with a sheet of plastic. Overspray will go everywhere....including the tail. Then wipe down those areas with denatured alcohol and hit the bare areas with zinc chromate....wait a day or three for the paint to totally cure and dry. Then have your favorite auto paint supply mix a color match in Urethane with gloss hardener. My shop charges about $30 for 3 oz of spray paint.....and it doesn't go very far.
 

Attachments

  • 64E1E668-F134-47D6-A0BB-22A3088397E8.jpg
    64E1E668-F134-47D6-A0BB-22A3088397E8.jpg
    201.7 KB · Views: 66
  • 4E8D04D5-3466-4153-8ED4-1962C3B89C6A.jpg
    4E8D04D5-3466-4153-8ED4-1962C3B89C6A.jpg
    175 KB · Views: 61
  • 520F384A-E619-4CF7-93A4-F31619A6C258.jpg
    520F384A-E619-4CF7-93A4-F31619A6C258.jpg
    188.3 KB · Views: 58
  • 95256CE2-CC23-4553-99A4-1C19A447D487.jpg
    95256CE2-CC23-4553-99A4-1C19A447D487.jpg
    199 KB · Views: 60
  • 192B447D-4C96-421A-8F15-03187A9F2B87.jpg
    192B447D-4C96-421A-8F15-03187A9F2B87.jpg
    151.4 KB · Views: 58
  • 9B4F0FEE-FAC6-4809-9C4E-4CD4E8B3AB0F.jpg
    9B4F0FEE-FAC6-4809-9C4E-4CD4E8B3AB0F.jpg
    147.8 KB · Views: 60
Last edited:
A couple things you should avoid.
DO NOT sand aluminum. you will destroy the al-clad coating and create more corrosion than you want to deal with next year.

Be vary careful with any stripper or other solvents around your windows, they are just plastic and you can ruin them pretty easy.
 
Tom....if there is pitting or any kind of corrosion....the al-clad is already gone so it won't matter. The corrosion has to be removed. Zinc Chromate will do the best in keeping corrosion stopped and under control.
 
Tom....if there is pitting or any kind of corrosion....the al-clad is already gone so it won't matter. Zinc Chromate will do the best in keeping corrosion stopped and under control.
Not true, pitting usually does not remove all the al-clad. some forms of corrosion does, but not pitting.
Zink Chromate is good stuff, but what we get now is not zinc chromate, it is zinc oxide, read the label.
The Op didn't say he was working corrosion. just wanted to touch up.
 
Not true, pitting usually does not remove all the al-clad. some forms of corrosion does, but not pitting.
Zink Chromate is good stuff, but what we get now is not zinc chromate, it is zinc oxide, read the label.
The Op didn't say he was working corrosion. just wanted to touch up.
I sincerely disagree....
 
Also,there is a tiny area on the leading edge of the horizontal stabilizer where the paint is slightly bubbled. I suspect there may be some slight corrosion starting underneath. I want to "sand" it down to bare metal, clean it up, prime and paint it with an airbrush. What are the proper materials to use? The existing paint is Imron.

Thanks in advance.

I see it now,, but don't sand it work the corrosion deposits out with a Stainless steel platers brush and clean with Alums-prep. and paint.
For small areas I use my airbrush, and after it has cured. buff / compound as required
 
I know we have discussed this in the past without resolution but regarding sanding of alclad; in past threads it was pointed out by others that the Cessna factory was lightly sanding the large areas between the rivets in order to enhance paint adhesion. I have stripped 150's that had the original paint to see this. Maybe it has since been discontinued....but there was no corrosion in the sanded areas and the paint was on there good, the ones I saw.
Just another viewpoint for the OP, as I am not going to be around for rebuttals as I know only too well how these go.
 
I know we have discussed this in the past without resolution but regarding sanding of alclad; in past threads it was pointed out by others that the Cessna factory was lightly sanding the large areas between the rivets in order to enhance paint adhesion. I have stripped 150's that had the original paint to see this. Maybe it has since been discontinued....but there was no corrosion in the sanded areas and the paint was on there good, the ones I saw.
Just another viewpoint for the OP, as I am not going to be around for rebuttals as I know only too well how these go.
This is exactly why you can't polish any Cessna painted at the factory. but their sanding is much different than sanding a local area to remove corrosion.
 
What's the best way to fix that
Here’s some basic info on painting and corrosion issues below. After reviewing these references you might have a better context to work in the other tips posted here.

As for Zinc Chromate primer, it is rarely used for surface applications now; replaced by two-part primers. Whoever you buy your touch up paint from will recommend the proper primer or paint system. A good airbrush or small gravity HVLP/LPLV gun will work depending on area to paint. There are many tricks to blending in touch up spots, but paint match could be difficult. Ask about it where buy paint or at a paint shop. Good luck.

Painting:
https://www.faa.gov/regulations_pol...raft/amt_airframe_handbook/media/ama_Ch08.pdf

Corrosion (8-15):
https://www.faa.gov/regulations_policies/handbooks_manuals/aircraft/media/amt_general_handbook.pdf
 
Thanks for the replies. The areas in question are small and I feel quite confident that I can tackle the job myself without much difficulty. I am going to wait until it warms up a bit but will post pics when I'm done.
 
Haven't used Imron specifically, but have used other 2 part urethane (Awl Grip) - nasty toxic stuff. But on the bright side, there is no need to spray for small areas - it flows out so nicely that brush strokes totally disappear.
I wouldn't use a "generic" rattle can primer (whether you get the actual zinc chromate or some zinc phosphate) under it if you want it to actually stick and not just lift the primer.
 
More touch up....
 

Attachments

  • 8D57C0E7-AB75-45B2-BF18-C75F40156372.jpeg
    8D57C0E7-AB75-45B2-BF18-C75F40156372.jpeg
    151.4 KB · Views: 28
  • F45DA7CC-E9B6-478A-BC9F-00C7CE439763.jpeg
    F45DA7CC-E9B6-478A-BC9F-00C7CE439763.jpeg
    145.2 KB · Views: 26
Tom....this is a touch up....like the thread title. What do you suppose is under my tape?o_O
 
Back
Top