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Clearcoat over polished aluminium?

Loman

Well Known Member
This may be a stupid question (from a newbie) but can you put a clear coat over polished aluminium?

I was thinking of a polished look, but the cowling and FG tips have to be painted anyway so a design incorporating solid colour on these and extending over parts of the rest of the plane is required. Why not use a base coat and clear coat system and extend the clearcoat over the polished parts as well?

Is there a problem with adhesion, or a chemical reaction with the aluminium, or perhaps the polishing compounds can't be removed sufficiently to give a clean AND shiny surface for the clear coat?

As a related question, for those who have polished planes, how do you clean at the edges of the painted/polished surfaces without damaging or contaminating the other side of the line?

Loman
RV9, Wings. Fuse on order
 
Clear coat will have adhesion issues to both polished bare aluminum, as well as out coated skins. Thermal expansion as well as flexing will cause cracking and flaking. Clear coats are hard and need lots of adhesion.

If you were just coating an aluminum something a ruther to sit on your mantel at home, you would be fine.

Best
 
Loman,

You might check this stuff out. It's a clear ceramic coating.

http://www.rfs-services.net/coatings.htm

I was considering the polished look myself and came across this. I was told that applying to an already polished surface is actually the preferred method for this particular coating. Another claim is that this creates a very slick surface that "nothing" will stick to once it is cured (e.g. bugs). I wonder if this would affect things like drag and stall speed?

Sounds like amazing stuff, but I have no experience to confirm these claims, just food for thought.
 
Ceramic coating seems to be something that might work. I did some web search and found out that there are actually quite many manufacturers for the stuff so it seems there are many possibilities. Also that this is actually not anything new but discovered already some time ago (~5 years). Also it seems to be used but as price is somewhat high it's used only on "better products".

Some brands and users for their products in car industry:

PPG: Mercedes Benz, BMW
DuPoint: Mercedes Benz,
BASF: Maybach, Rolls-Royce, Mercedes Benz
Unknown brand: Ferrari

It seems that some are not talking too much about ceramic but rather nano technology . Auto forums seems to have much more info about his so for further info that might be the place.

Some general stuff about these coatings (Jan 2006):
http://www.carwashmag.com/pdf/jan_2006/german.cfm

PPG Ceramiclear Clearcoat:
http://corporateportal.ppg.com/NA/Coatings/AutoOEMCoat/100_Products/160_ClearCoat/

DuPoint Ceramic Coatings:
http://www2.dupont.com/Directories/...Paint_Coatings_Finishes/Ceramic_Coatings.html

I couldn't find proper link to BASF procuct.
 
True, however...

...the degree of difficulty of removal of smashed bugs can vary widely depending on the surface condition.
 
Yeah, but what do you use to clean painted/polished planes?

Thanks guys. These responses are great. Now I have a whole new line of research to follow - part of the fun.

I am still interested to know about cleaning on the paint/polish boundary though. That seems to me to be a problem area, at least as far as any cleaning compound goes, and every polished plane has to have these boundaries where metal meets fibreglass, so someone must have come across it.

Comments anyone?
 
Wouldn't it be cool if somebody could figure a way to put a matte color anodized finished on the skins?
 
Clear Coat

This may be a stupid question (from a newbie) but can you put a clear coat over polished aluminium?

I was thinking of a polished look, but the cowling and FG tips have to be painted anyway so a design incorporating solid colour on these and extending over parts of the rest of the plane is required. Why not use a base coat and clear coat system and extend the clearcoat over the polished parts as well?

Is there a problem with adhesion, or a chemical reaction with the aluminium, or perhaps the polishing compounds can't be removed sufficiently to give a clean AND shiny surface for the clear coat?

As a related question, for those who have polished planes, how do you clean at the edges of the painted/polished surfaces without damaging or contaminating the other side of the line?

Loman
RV9, Wings. Fuse on order

Loman:

Go to the Nuvite Polish Web Site. I don't have that address handy but you can Google it. They don't recommend any coating over their polish. Read through their info thoroughly.

Polishing is initially a pain in the ***, but it gets easier with each polish. After a couple of times polishing, you can essentially go for a year between polishing and it won't take longer than waxing.

Initially you will have to mask off the bare metal/paint boundaries when you "compound" the aluminum. Later with the "S" grade you don't have to do that, just be careful that you don't dwell to long on the paint/decals.

Hope this helps. To each his own and this is just my two cents worth!
 
Don't do it!

Airstream trailers have been clear coated since 1964 and not one of them will last very long. The factory now installs a mill finish aluminum with a factory applied clear-coat and I've seen them fail in 2 years. It has to do with the coefficient of expansion of the two materials vs. the adhesion between them. Failed clear coat looks way worse than oxidized 2024 alclad aluminum. I would bite the bullet and do a full polish with Nuvite:

http://www.perfectpolish.com/

Other than time, you won't regret it.
 
Don't do it!

Airstream trailers have been clear coated since 1964 and not one of them will last very long.

If you read anything above, you most probably noted that these ceramic coatings we've been talking has been developed like 40 years later than the moment you talk about... and do you seriously thing than Maybach and Rolls-Royce would use some clear coat which would suck like that?!

Also comments about polishing: polishing is fine, but this thread was about coating the polished plane.

http://en.wikipedia.org/wiki/Maybach
http://en.wikipedia.org/wiki/Rolls-Royce_(car)
 
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I'd like to Restart this topic

I looked at the archives on Clearcoating over polished aluminum and found this thread the most helpful. Still, I have a new question for you painters and you polishers.

I am beginning to paint my RV-4 something like an old Swift with part painted fuse and part polished aluminum. I'm putting no paint at all on the underside of the wings and fuse. I am in the middle of a Nuvite polish job (C then S) and once it's finished, be ready to paint the parts I want color on.

Here's the thing....a local artist is going to do tail art for me and he (almost) insists on clearcoating his work after. He claims that there is an Italian clearcoat (Vist**** somthing or other) he did over his bosses entire polished plane that is very flexible and it is totally durable and won't crack or yellow. This saves the coarse edges of clearcoat just over the art, and on a partially painted plane, the coarse edge where the paint meets the aluminum and stops. He wants me to just clear the whole plane once he is done and the paint is on where I want it.

Any thoughts? Should I just protect the art with clear and live with the edges and the routine polishing of the bare surfaces?

Ron
RV-4
N8ZD
 
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If there was a good way of applying a clearcoat over polished aluminum that both lasted long enough and looked as good as bare polished aluminum on an aircraft, there would probably be thousands of plane owners doing it already ;)
 
Xzilon

I am new here so if this is a repeat please forgive me.

It's is a clear product put on by hand. Extends the life of the polish job.
 
Look at Don Shorts RV

Should talk to Don Short, his RV is the one on the vans calendar with the girl putting on lipstick using his polished tail. Dons RV-7 is a combo of metallic paint and polished aluminum all covered with clearcoat. It has been flying for 7 years and still looks great, he can explain the process he used and it was a lot of work and took quite a while to finish.
 
Any thoughts? Should I just protect the art with clear and live with the edges and the routine polishing of the bare surfaces?
That's what I would do.

You can polish the aluminum right up to the edge of the paint (or clearcoat) and even run the polisher over the paint to make sure you get all the aluminum. This will leave a grey or black haze at the edge of the paint, but that will wipe off with a rag moistened with some mineral spirits. Works with paint or vinyl decals.
 
Polished protection

Call Stewart Systems. They have clear material that they claim will resist SS exhaust discoloration, protect paint and release bugs. Might be your answer for Aluminum ??
 
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