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Cost of paint!

Carl Froehlich

Well Known Member
Today made the trip to the local auto paint store for more PPG DP-40LF primer for the new RV-10 build. With activator it is now over $700 a gallon!

After this set in I asked about costs for PPG base/clear as final paint is 18 months away or so. While I did pick a very expensive red (tri coat Mazda Sole Red) a quick estimate put me well over $7K - just for the paint. I note this is three times the cost of using the same PPG base/clear paint on the first RV-10 back in 2011.

Good thing this is the last project. The kit, engine and avionics price increases are really hitting home - I'm broke!

Carl
 
FWIW, you can get 8 gallons of the Akzo primer for that price from skygeek + shipping. Or about 6 gallons from SPI, shipped.
 
Today made the trip to the local auto paint store for more PPG DP-40LF primer for the new RV-10 build. With activator it is now over $700 a gallon!

After this set in I asked about costs for PPG base/clear as final paint is 18 months away or so. While I did pick a very expensive red (tri coat Mazda Sole Red) a quick estimate put me well over $7K - just for the paint. I note this is three times the cost of using the same PPG base/clear paint on the first RV-10 back in 2011.

Good thing this is the last project. The kit, engine and avionics price increases are really hitting home - I'm broke!

Carl

The price of paint, especially the type you are aiming for, is very high. I have had my plane painted with a similar candy type (tri state) and a few years ago it was $1500 a gallon.
 
Yea, the almighty dollar is loosing value by the tweet ...

There are other options for around half the price ... two that come to mind:

Air-Tech
Stewarts
 
Just bought a quart of red paint. Nothing really special. Just single stage red. $200. A gallon of the same color was $625.
 
Kirker Ultra Glo

I know no one wants to use it but I've had great results.
3/4 gallon is $100. Add activator and clear.
 
There is quite a broad price spread between various product lines of essentially the same paint formulation within PPG. A gallon of single-stage white PPG Concept is something like $900. But a gallon of single-stage white PPG Shopline JAU is about $350. I just bought 2 gallons of JAU, plus activator, reducer, and plasticizer, all for just under $1000. It was enough to paint a full set of wings and have 1/2 gallon left over.

(these were composite wings, which got 4 wet coats so that there was plenty of paint to block-sand out any waviness. You probably don't need to plan to put so much paint on. I would think 1 gallon should do a pair of RV wings?)
 
I like PPG Concept but it is rather spendy. However I am using it on my RV exterior to get the color I want. A friend suggested Summit Racing's Acrylic Urethane as an alternative for other things. I bought some basic black, white and silver and really like it. It lays down like Concept but is only ~$100/gal. I'm using it where I can on things like like engine mounts, gear, inside cowlings, etc. They only have about 80 colors but if any of them suit your needs it's worth a try.
 
Kirker

I like PPG Concept but it is rather spendy. However I am using it on my RV exterior to get the color I want. A friend suggested Summit Racing's Acrylic Urethane as an alternative for other things. I bought some basic black, white and silver and really like it. It lays down like Concept but is only ~$100/gal. I'm using it where I can on things like like engine mounts, gear, inside cowlings, etc. They only have about 80 colors but if any of them suit your needs it's worth a try.

Summit and Eastwood are manufactured by Kirker. Prices are similar but each has some unique colors.
 
Carl, console yourself with this thought: Mazda Soul Red is the most beautiful color in the universe - and you're getting it for under an AMU per gallon.

And, no - Stewart Systems cannot duplicate the tech - I asked.

Your 10 will look like a burning ruby, the envy of the flight line.

YOLO.
 
Today made the trip to the local auto paint store for more PPG DP-40LF primer for the new RV-10 build. With activator it is now over $700 a gallon!

Carl

There are often several price tiers at the auto body supply store. There's the body shop price, the price for local independents, and the price for a guy off the street. Sometimes you can buy paint through a body shop at their price plus a small markup. Sometimes, the paint store will sell at the "body shop" price if you pay cash. Ask the friendly guy at the paint store counter if there's a path to a cheaper price tier. Maybe all you have to do is open an account.

The difference between the Body Shop price and the Guy off the Street price is substantial at my local PPG store, so it may be worth your time to inquire...
 
There are often several price tiers at the auto body supply store. There's the body shop price, the price for local independents, and the price for a guy off the street. Sometimes you can buy paint through a body shop at their price plus a small markup. Sometimes, the paint store will sell at the "body shop" price if you pay cash. Ask the friendly guy at the paint store counter if there's a path to a cheaper price tier. Maybe all you have to do is open an account.

The difference between the Body Shop price and the Guy off the Street price is substantial at my local PPG store, so it may be worth your time to inquire...
Same for me. All they wanted was a business card to set up an account. Fifteen minutes later on the computer earned a 15% discount if I recall correctly, and they worked with me when I made the big base coat, clearcoat purchases to get me more since I was buying top shelf products.
I will tell you that they don’t want to be your teacher, at least not the shops around here, so do your research first and have a clue what you’re talking about and need or else you get the “remain clear of the class B” treatment!
 
Technical clarification

There is reference to epoxy primer. It is is my understanding that this should/be preceded by some form of abrasive acid etch.

By contrast, other systems suggest an abrasive scrub followed by an acid based ETCH primer.

Is this correct ?

Also, my Spies Hecker ( Axalta/Dupont) instructions say the etch primer must be followed by 2K primer surfacer before base/clear shall be applied. Just fyi.
 
I’m not a big fan of etch primers. I’ve delt with a bunch of planes in the past that had corrosion issues because of etch primer. It only takes about an hour to wash an RV with soap and water then wash with an etch solution.
 
Bandera question

I apologize for the thread drift but your comments raised this question for me. The issue can affect paint system selection, cost and results.

I have done the scothbright/acid etch / rinse process on a Stwart System painted project but the primer was waterborn and NOT solvent resistant. It adheres vary well.’ I read the ekopoxy primer also adheres well even validated by tape strip testing.

The primary advantage of etch primer in my mind is the “dry prep” option. You dont have to hose off a fuselage or wing to assure the acid is all gone. Then to assure it is all dry enough to paint, the aluminum will oxidize back to the condition you sstarted with before the etch/scrub according to some references 😏
So for a solvent based, base/clear system, what are the primer options over acid etched aluminum ? Apparently the concern for reoxidizig is a wives tail and epoxy or urethane catalyzed primers will stick to the scuffed texture of oxidized aluminum ?
 
Eastwood worked for me

I painted my RV-7 in pieces at home before moving to the airport to assemble and used Eastwood basecoat-clearcoat automotive paint over their self-etching epoxy primer. I achieved what I consider excellent results. At least we keep getting a lot of compliments on the finish.

The price was no cheap, but way less than any of the paint systems intended for airplanes.

It's been painted for about two years now and still looks new, although it is hangered.
IMG_0148.JPEG
 
Apparently the concern for reoxidizig is a wives tail and epoxy or urethane catalyzed primers will stick to the scuffed texture of oxidized aluminum ?

Sorry, but oxidizing aluminum is pretty basic science. The primary reason that aluminum doesn't corrode is the thin oxidized layer created. Corrosion creates the layer, but once there, that layer greatly reduces future corrosion. That layer does not have good bonding to the base aluminum, so anything adhering to the layer will stick just fine to the layer, but run the risk that the layer separates from the base aluminum.

The layer must be removed either chemically (etching chemicals) or mechanically (sanding/scuffing) or converted to something different that bonds to the base aluminum chemically (i.e. alodine, etc.) if you want good, long term bonds. The oxidation begins the second you remove the old layer. The only question is how long before enough oxidation occurs to impact adhesion performance. recommendations seem to range from 2 hours to 24 hours, with most closer to 4. Ignore this at your own peril.

The reason that alodine is so effective is that the conversion leaves a new surface coating that will no longer oixidize and also creates chemical bonding with paint. This does NOT occur with acid etches; They just chemically strip the oxidize layer, exposing the base aluminum, which will immediately start forming a new layer.

I scuff with soap and water until break free water flow. Let dry for several hours or overnight (preferrably in the sun) and air spray stubborn areas. Then just before paint I lightly scuff again dry this time, blow off with air and remove the scuffing residue with solvent based W&G remover (Must keep wiping until towel has no grey). Wait an hour for full flash, then spray. I think you will find most pro's familiar with Al do something similar, assuming they don't use alodine. Can't follow most of the auto guys as they work almost exclusively with steel which doesn't have the same issues; It requires moisture to oxidize and if you can keep moisture at bay, it won't oxidize for months or years.

Larry
 
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Thanks LR172

This 2-24hr window referenced is at the core of my question.
1- Does all the acid rinse water dry from crevice's and lap joints in 2hrs, probably not.
2- Wash/Etch primers over scuffed aluminum are probably adhered to the oxidized layer (alcad ) if you don't spray within 2hrs or, do you trust the assumption 24 hr is OK.
3- Epoxy over scuffed appears to have the same risk as wash primer if applied after 2hrs.

Not trying to be PITA, just observing opinions / references that do not close the loop on this oxidation window issue.
 
This 2-24hr window referenced is at the core of my question.
1- Does all the acid rinse water dry from crevice's and lap joints in 2hrs, probably not.
2- Wash/Etch primers over scuffed aluminum are probably adhered to the oxidized layer (alcad ) if you don't spray within 2hrs or, do you trust the assumption 24 hr is OK.
3- Epoxy over scuffed appears to have the same risk as wash primer if applied after 2hrs.

Not trying to be PITA, just observing opinions / references that do not close the loop on this oxidation window issue.

You don't need two kinds of removal. Either chemical or mechanical is fine. As I mentioned, chemical requires a rinse and rinse requires drying to avoid other problems. I am friends with the owner of Southern polyurethanes and he has been designing and manufacturing Urethane paint for decades and sprayed it for decades before that. He tells me that with AL, 4 hours is the max between scuff and spray and 2 is preferred. I tend to trust him more than some guy on the internet. FYI, he does not like acid etch products and prefers scuffing. It isn't that the process doesn't work, more that many painters don't rinse effectively and any acid left on the surface destroys the primer bond and results in complaints to him. Apparently the amount of rinsing required with acid is significant and many don't understand it. Ospho (Phosphoric acid and water) is the only etch that he allows with his primer. He is not a believer in self etch primer and therefore doesn't make one.

Based upon the above, No, I would not trust a 24 window between oxide removal and spray.

Larry
 
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There is no issue waiting longer than 2 hours after etching. Your parts need to drip and dry before doing any primer work. If your plane is complete that needs to be over night. Even if it was dry before 2 hours now you need to mask off the things that don’t get painted. On your average RV just that takes two guys around 4 hours. One thing I won’t do is wash an airplane on a Friday.
 
Somewhat basic questions here, and it's probably covered in another threat so point me in the right direction if needed. Considering painting with Stewarts System but a buddy tells me its not as easy to shoot. He recommended to keep costs down and get a decent coating to use Delfleet, Aerothan or Emron. Anyone have any experience with any of the aforementioned coatings? Good, bad ugly?
 
Somewhat basic questions here, and it's probably covered in another threat so point me in the right direction if needed. Considering painting with Stewarts System but a buddy tells me its not as easy to shoot. He recommended to keep costs down and get a decent coating to use Delfleet, Aerothan or Emron. Anyone have any experience with any of the aforementioned coatings? Good, bad ugly?

Delfleet is an automotive line of paint. It dries fast and can be tuff to keep ahead of when painting larger things. PPG makes very good paint but not my first choice for airplanes.

Aerothane can be a real ******* to paint. I’ve sprayed a bunch of it. I’d rather spray something else if given the choice.

Of the three paints you have listed Imron is the best. It’s a good looking paint and fairly forgiving when spraying. It will buff pretty well if you have an imperfection that needs taken care of.
 
I painted my -3b as well as a pedal plane with Stewart systems. It’s difficult to get a melted glass finish, but with practice at can be done. You can search my posts for more details. It’s very durable and holds up well over time. Cleanup and health concerns are the main selling point.

I recently painted a carbon bike frame with House of Kolor voc based paint. Wow what a difference. You can achieve amazing results with half the skill and technique.
 
...so do your research first and have a clue what you’re talking about and need or else you get the “remain clear of the class B” treatment!

Now that's funny ;)

The oxidation begins the second you remove the old layer. The only question is how long before enough oxidation occurs to impact adhesion performance. recommendations seem to range from 2 hours to 24 hours, with most closer to 4.

There are quite a few scholarly papers out there regarding oxidation of aluminum. In a quick scan, they all seem to say the initial rate of oxide formation is very fast, but slows logarithmically. For example, thickness is commonly given as 2nm in a few hours, but might only be 4 nm in a year.

Here's where I'm going. We scuff to remove the oxide layer, but it forms again almost immediately. Assume it builds to 2nm thickness in an hour.

Consider the scuffing process. A maroon Scotch Brite pad is 320-400 grit according to 3M literature. A good rub of the surface leaves a pattern of scratches. Those scratches have a depth, which varies with pressure, lubricant (i.e. soap and water), and grit wear. How deep do you think the average 400 grit scratch might be?

I don't know for sure, but a quick survey says it's a lot deeper than the 2 nanometer oxide thickness. 2nm is is a fuzz less than 0.00000008". My guess is scratch depth for 400 grit on aluminum is something like 0.00001".

I think what really happens is (1) oxide re-forms no matter what process we use for initial removal, the variable being thickness vs time, and (2) what we're really using to keep the paint on the surface is mechanical grip based on surface roughness, that being much, much deeper than any likely oxide layer.
 
(2) what we're really using to keep the paint on the surface is mechanical grip based on surface roughness, that being much, much deeper than any likely oxide layer.

Appreciate the data. While i fully agree that mechanical abrasion is key to a good grip and the scratches are much deeper than 2nm, they are also wider than 2nm, and therefore I would make the argument that the oxide layer is also forming inside those .00001 scratches as well and it is the weak bond between the oxide and Al that causes the issue.

I don't have all the answers here and hope that I have portrayed that fact. However, I still would move quickly between scuff and spray. I suspect that several of the paint makers have done some testing, charting adhesion performance against time from etch to paint on alum surfacs and therefore will follow their guidance until I find enough science to prove them wrong. Maybe I should go try to find some of that testing data. There is a reason that a lot of Al painters use Alodine. It removes this issue from the equation and speculate it was created due to adhesion problems with Al before it's creation.

Larry
 
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Not a lot of paint data, but a lot of data on time vs shear strength with structural adhesives on etched Alum. Seems that strength drops over 30% from best at immediate to worst in about 24 hours (though they noted a continued but limited degradation out to 72 hours) with the median loss right around 2-3 hours, so consistent with what I have been told in the past with paint. These tests used an environment friendly etchant and not mechanical. Obviously not a direct correlation, but seems to address the same issue and IMHO corroborates what I have been told by paint makers.

Cal Poly research
https://www.slideshare.net/MatthewErich/effect-of-time-delay-between-etching-and-adhesive-bonding-outli

Larry
 
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