Aircraft painting

[Dash8capt]

A quick question, it has been discussed before but i dont believe the firm answer i am after was included. What is the legislation around painting of an aircraft (certified) if you are not a lame or ame, but you are a pilot? Under schedule 8 it states - Application of preservative or protective materials. - as long as you have not disassembled primary structure. Is there anything stopping you from painting your aircraft if you were to have a lame remove anything you required removed and then after you had finished painting, reassembled and have the aircraft re weighed? I am not looking for people stories of how joe blogs painted his plane with a roller and dulux. I'm just after the facts.

[Engineer_aus]

A paint job is merely a paper reweigh, pending that it is with in 3%.
However when you paint any flight controls they need to be re balanced. Essentially anyone can repaint a aircraft but you still need a LAME to carry out the paperwork in an approved maintenance workshop.

[Dash8capt]

Engineer thank you very much :)

[baron_beeza]

It will vary from country to country. Generally the repaint will need some form of certification.

Often you will see that the owner can do so much area. Naturally all maintenance should be assessed to see if it requires a release to service anyway. Pilots can obviously sign the release iaw the applicable procedures.

The very real trap now of course is that with monocoque construction the aircraft skin is structural. Ageing aircraft requirements may have to be taken into consideration if any stripping is involved.
Generally there will be extensive inspection, corrosion removal and other repair work involved. (At least with the average GA machine).

The other issue that we now have is that the current generation of paints may not necessarily form an effective paint system. The biggest issue there would be the removal of Chromates that the 2024-T3 alloy often relies on for corrosion resistance.

I have seen two botched jobs in recent years where all the paint had to be removed again. The automotive painter had not realised that the aircraft alloys required a chromate pre-treatment or a PreKote treatment combined with chromated primer.

It would probably be best to work in with the guy who will be doing the certification and reweigh. It is always better to do that earlier than to discover that the job has been botched.
The LAME may not be impressed to have a freshly repainted aircraft just rock up to the doors either. He may have some pretty tough questions.

If it is a Cessna then you would really want to be looking at the SID's requirements at the same time.

I see you are talking Certified machine so you will have to tread reasonably carefully. I gather you seem to be considering a scuff and respray, just some precautions regarding static system, aerials and transparencies to be considered in that case. Exterior markings would be expected to comply also.


With the modern peroxide strippers I would not even consider painting over old paint now.
I have stripped two aircraft recently and about to do two more. All have corrosion that was unseen under the old paint.

Don't seek advice from the homebuilder fraternity either. I have looked at numerous websites in recent months and many of their paint systems were flawed. They may get away with it for a while as they generally used new alcad and the surface of course is still intact.
Aircraft paints are going through a massive change at the moment, we are getting all PC and phasing chromates out. You really need to do your homework these days.

www.youtube.com/watch?v=MXzNqVivsDM

[hiwaytohell]

D8 Capt, a full repaint is not a schedule 8 job. Schedule 8 was designed to repaint the back of your prop, polish your aircraft etc.

The full repaint needs to be undertaken by a shop with the appropriate certificate of approval and supervised / certified by an appropriately qualified LAME.

Many shops will permit you to provide the "grunt" labour. However there are a lot of pitfalls for the amateur. Some examples I have seen:
* using acid stripper on Baron elevators (made of magnesium alloy).. required a full re-skin of elevators. I have seen this about half a dozen times over the years.
* paint stripping the plastic & fibreglass. I saw this on a Seneca completely stuffed the engine nose cowls, the cabin door (made of fibre glass), all wing tips etc
* a C182 sanded with an orbital sander that took the heads off 80% of the round (universal) head rivets on the wings and fuselage. Plus badly took the surface off the alclad... wrote off the aircraft. I also saw similar on a C188 required replacing a lot of rivets.
* overly vigorous use of the pressure cleaner on the paint stripper forcing stripper under masking on windows. In one case on a Baron required replacing windscreen and all windows. Also saw same on static vents, in one case stuffed the entire system (due plastic lines) and the ASI, ALT and VSI.
* use of steel scrapers that have badly scribed skin. In one case required skin replacements.
In a few of the amateur assisted paint jobs I have seen the longevity has been pretty short. Such as stripper leaking from skin lap joints (due to stripper being forced under with pressure cleaners), corrosion because surface treatment was done incorrectly. I could go on...
Get a professional shop who do paint jobs for a living. If they will let you help great! But you are unlikely to save much doing it yourself!

AND definitely don't get the apprentice panel beater who does up punky boy cars...

[Dash8capt]

Thanks very much guys appreciate all your info. Am not considering it myself but wanted to know the regulations around it, As from previous posts it seemed as though some may have done it themselves in the past with varying results. :ok:

[Wally Mk2]

That's an interesting post there AC/DC:ok:

Just adding to those poor A/C paint jobs stories you mentioned as the initial question has been answered quite well I think.
Back in the late 70's at EN I recall hearing a story of a C337 being dismantlement & paint stripped off the airport close by though that was essentially written off due to the medium used to strip the paint,sand blasting !!! The Alclad was ruined but it did get rid of all the paint & some!:)
I used to do a bit of part time work up in BLA many years ago doing re-painting of A/C. It would have to have been the most god damn awful job I have ever undertaken,paint stripping with that gooey yellow paint stripper !!! I think a re-paint of yr A/C you can expect to pay a gazllion $$$ for it as it's worth that for sure !
Can you believe that idiot in the YouTube link here doing what he is doing with no protection to his person at all!!!:ugh:

Wmk2

[Arnold E]

Can you believe that idiot in the YouTube link here doing what he is doing with no protection to his person at all!!!:ugh:
Yeah, imagine what that stuff is doing to his lungs. Also notice that he is high pressure spraying against the lap joints, not with them, thereby forcing water and contaminate under and between the joint.

[baron_beeza]

The paint stripper being used in the Youtube link is new generation Peroxide/Alcohol. It is basically like hair shampoo.
Almost completely inert but you would certainly want to wear eye protection and not leave any on exposed skin for any length of time.
It is a completely different beast to the 'old' Tergo and similar products we used to use.
This stuff also works from the inside out, it does not penetrate each outer layer individually like the old products did. The new strippers loosen the bond between the paint and substrate, the result being the paint literally drops off.

The water kills it dead, it cannot leak out of the laps and Sodium Dichromate solution can be used as part of the pre-treatment rather than Chromic acid. PreKote will then give an excellent bond into the lap when used with a Chromate primer or one of the latest MgRP products.
The system is completely different to the acid etch, alodine etc process used just a few years ago.

The systems in use next year will be 100% environmentally friendly. The stripper, pre-treatment and primer will all be non-hazardous.


Have to agree with the recent replies about problem areas.
The SID's repaint of the Cessna mainleg tubes requires stripping by alternate means, not chemical.
Cessna now have lap joint inspections also.

These are the areas where the novice can cost a lot of money, thousands more than the job itself.

It would probably be best to work in with the guy who will be doing the certification and reweigh. It is always better to do that earlier than to discover that the job has been botched.
The LAME may not be impressed to have a freshly repainted aircraft just rock up to the doors either. He may have some pretty tough questions.

[LeadSled]

Folks,
This reminds me of the 3-tier hourly rate:
1) Normal Rate: $80 per hour.
2) If you watch: $160 per hour.
3) If you help : $210 per hour.

Seriously, all the warnings about pitfalls of painting an aircraft are true, and I could add a few more horror stories. Now that quite a few automobiles have other than steel in the bodies, there are some interesting stories of backyarder tales of woe.
Tootle pip!!

[Clearedtoreenter]

Folks,
This reminds me of the 3-tier hourly rate:
1) Normal Rate: $80 per hour.
2) If you watch: $160 per hour.
3) If you help : $210 per hour.

Seriously, all the warnings about pitfalls of painting an aircraft are true, and I could add a few more horror stories.

And how many us have horror stories of ending up with disasters and paying through the nose for some of the so called experts WITH all of the approvals?

I have had 3 aircraft repainted... and I'll NEVER do it again. I sell it, scrap it, give it away, pay to have it taken away... ANYTHING but not get into painting.. ever!

It takes for ever, (one took 6 months after being 'quoted' 5 weeks - and not because it was worked on for more than about 3 weeks all up either!) the 'estimates' are just a joke, all of them looked nice and shiney when they came back but actually were quite dissappointing in their detail finish and durability (not that they were actually finished.) In all cases its been a matter of having to pay someone else to remove stripper, finish off something, remove masking properly, sign something out properly etc etc) And as for 'under the supervision of LAME'... that really makes me laugh! My advice/experience would be 1. Dont do it! or 2. if you must do it, do as much as possible yourself and keep a VERY close rein on anyone you are paying... I've heard its over-exposure to paint fumes that causes the problem.;)

Seriously though, it really is a cr@p job. Fumes, chemicals, dust, water, heavy, backbreaking work. Frustrating as I've found it, can't help having a bit of sympathy for those guys too.

[jas24zzk]

You are right CTE.....painting is a pr*ck of a game.

Leadie.. I'm a panel beater by trade, and I CAN paint....i prefer mi****ting with a hammer and mashing my fingers than the mental frustration of paintwork gone wrong.


Baron, I wouldn't mind some more info on Peroxide/Alcahol paint strippers. They are not something that has found their way into the auto industry as yet. From the limited info I have found, they seem to be more effective on 2K paints than acrylic/jam (enamel). Looking at the video presented, i like the surface finish.


A question on media blasting. Sand (garnet) is never going to work on an airframe (not rocket science). However, what about Plastic bead, Soda or even walnut shell ??

[Sunfish]

Beezer, by coincidence I was painting parts of the new experimental Flying Fish last week.

6061-T6

Acetone, sugarsoap, 3M Red scouring pad followed by Alumiprep and Alodine with lots of rinsing.

Sherwin - Williams strontium chromate Two part epoxy aircraft primer.

Respirator, suit and safety glasses.

Primary structure joints (but not the skins) rivetted together wet with AC240 B2 sealant for a little more corrosion protection and peace of mind.

Topcoat will be Sherwin Williams aircraft paint IAW their instructions.

That OK?


...Yes, it's a prick of a job.

[baron_beeza]

The paint stripper we have been using is not cheap. While there is an aviation version the same company also produces similar products.

Sea To Sky Innovations. (http://www.sea2sky.co.nz/viewproduct.aspx?ID=386)
http://www.sea2sky.co.nz/Images/ProductImage/SPC909.jpg


Sea To Sky Innovations. (http://www.sea2sky.co.nz/viewsubcategory.aspx?id=49)
This is possibly the equivalent product for use on commercial vehicles.

The SPC-909 certainly has no problem removing acrylics and acrylic enamels I may have tried it on some enamel. One tab we had had been repainted ?? and was something altogether different. It may have been enamel and while the stripper loosened it it did not peel off but rather went gooey. I think it may have been some unusual paint and while could be scraped off it was nothing like the rest of the aircraft.

This stuff likes the heat and works best at 20 to 25 degrees. The paint peels off like wet newspaper and can be disposed off easily. The waterblaster can be used just for the clean-up.

Media blasting and indeed hydro-blasting have been used on aircraft but a massive amount of damage can be done if used incorrectly. I think both are fine with skilled and experienced operators.

[baron_beeza]

Sherwin - Williams strontium chromate Two part epoxy aircraft primer.

Hi Sunfish. I can't really comment on that other than to say that the paint has to be a system, it seems you are using a Sherwin-Williams system and will be fine with that.

You have used Alodine which gives you your conversion coating and adhesion so that is good.

Strontium Chromate Two Part Primer is the way I have been going myself. The problem we have in NZ is that the product is no longer available, at least not readily.
The danger is that the manufacturers are now selling a 'similar' primer. Without the chromate it is not going to provide any corrosion resistance on the 2024 or other alloys.
Magnesium is going to be the the base for a suitable new product but you really need to ensure it meets a Mil Spec or similar.

I think you have used a good system, and addressed each step in the process.

It is the guys that use a A, B, A, A system that come unstuck....
You have to use a complete and compatible system.

You can see why the LAME may not be entirely happy if someone has missed a step or used an incompatible product.

Of course the painter or owner just didn't know... they are often more than a little surprised to discover all their work is worse than worthless.

PreKote with a Strontium Chromate Primer is the method a few of us have been using in recent years. The Topcoat can then be matched to the Primer.

Super Air - Aircraft Painting (http://www.superair.com.au/aircraft-painting.aspx)

There are many different ways of painting an aircraft. They just cannot be mixed up, - what is good for one aircraft may not be suitable for another.

[LeadSled]

Clearredtoenter,
Sound like you have been dealing with an organisation that advertises quite widely of their aviation painting business ---- or their equivalent.
No names, no packdrill, but the fact they advertise widely in the aviation mags., is not an indication of quality.
Tootle pip!!

[Kulwin Park]

Baron beeza - what informative & interesting posts you have made, contributing faith in some that want to get a decent paint job on their aircraft!! :D

Another question... Do you believe in using several clear top coats, or prefer to just use the base and colour coats? And how much weight do clear coats add to an average 4 seater cessna? Just considering that due to it's hard to get hangarage at cheap rates, and aircraft have to live outdoors most of the time.

Cheers, KP

[baron_beeza]

Hi KP, thanks for the compliment. I have spent some weeks trying to source a suitable primer for the PreKote which is why I chipped in.

I am not a professional painter, just a LAME. It is the structure and corrosion prevention treatment that concerns me more than cosmetic finish.
Naturally these are often the parts of the repaint that get forgotten when done by backyard painters.

A good paint job will give a durable and strong waterproof finish with good lustre.
A bad one naturally may not give any of them.

I am not in a position to answer your question. I have seen clearcoats fail, as indeed we all have on cars as well as aircraft.
I would recommend you ring a painter that works on helicopters. They have attractive, colourful schemes and normally present better than a GA aircraft.

If you use a two pack primer then your topcoat (colour) would be a two pack also and have all the properties we require. A regular buff and polish should give years of use. It is the preparation that is ultimately responsible for the durability of the paint job.

If you use a colour system with metallics then you will be into the Base Coat-Clear Coat system.

The base coat will be dull/flat and the clear coat is required for the lustre.

I could not tell you how much extra weight is applied.

This guy seems to be onto it..
Basecoat -clearcoat secrets revealed - YouTube

Graphics are being used increasingly now also, another consideration.

[Kulwin Park]

Thanks BB . That YouTube Video was excellent. Knowing the basics is great. Quite a detailed operation. Maybe with a paint booth, it cuts out sanding surface dust in between.

I will do some research to see what paints weighs more actually.

[jas24zzk]

Actually you cannot weigh what is in the tin, and then try to calculate that back to what you apply, unless you are pouring it on.

When spraying as much as 60% (dependant on spray gun, conditions, painter) can be lost to the atmosphere.

[Jack Ranga]

Sunfish, mask it properly. You don't want overspray on or in your single radio :ok:

[Kulwin Park]

Check if Aeropaint Australia is still going in Horsham VIC ?? They used to be great, and not far fly from NSW...

[flywatcher]

The best quote is not always the best. Got a full respray done in Moorabin in mid 90's. They were accepted as the best at the time and their quote was 30% over most of the others. A couple of people told me I was stupid paying that much over the norm but after all these years, with occasional polishing, the paint is still almost showroom and the new owner is extremely happy. The people who told me I was stupid have had a couple of repaints over the time, have paid a heap more than I did, and still have ordinary paint. The moral of the story, find the best, don't scimp, don't try to negotiate the price, make sure inside cowls and inspection plates are chromated and don't hang around. Go and do something else and come back when they tell you it is finished.
This advice is worth what you paid for it.

[Ultralights]

is it better to Polish paintwork, or wax it?

[Flying Binghi]

is it better to Polish paintwork, or wax it?

Just leave it in a 'natural' unwashed state and call it a Rat Rod..:}

[gassed budgie]

The last time I asked (just before Xmas) how much it was going to cost to paint the 210 I was told nothing south of $25,000. Add on the inevitable other bits and pieces that will crop up and you won't get any change out of $30k. The windows should all be replaced at the same time. Nothing worse than seeing a flash paint job downgraded with the original ****ty Perspex. That'll be another $5,000 at least. So nothing left out of $35k and the 210 is one of the simpler aircraft to paint (the later ones that originally didn't have the gear doors).
The 172 won't cost all that much less (maybe a tad over $30k to do it properly), but fortunately that's already been done.
Someone above mentioned a Warrior. I would have thought that would be done for around the same money as a 172. If it's already stripped I'd reckon you could knock off about 10% (maybe) of the original quote if the paint was still on it.

....and what flywatcher said.

[Sunfish]

The only thing I know is that preparation and good foundations are the key to any paint job in any application, home, marine, aircraft, cars.

The build is getting Sherwin - Williams Strontium Chromate Two pack polyurethane primer.

That is going over Alodine for the little parts, or Sherwin - Williams wash primer for the bigger bits I can't dip.

The top coat will also be Sherwin - Williams, which will be applied by a professional using airless spray equipment.

The cost? Wash primer $245 per Gal. Polyurethane primer $500 per gal. However I have to say it sprays on like a dream and covers a multitude of my sins. The test panel I made shows it is as tough as nails and sticks like the proverbial.

I was reminded how good it is when I bought some Dulux rattle cans of primer and gloss from Bunnings to paint some 4130 steel parts. Talk about crap paint! They are now binned and I'm using Norglass marine primer and Two pack for the steelwork.

Most "structural" bits like doublers where water might pool and all dissimilar metal joints are sealed with AC240-B2 polysulphide rubber fuselage and fuel tank sealer (AKA "brown sh!t" in the old days at Ansett, and a pretty good description when you try to apply it)

[Clearedtoreenter]

The last time I asked (just before Xmas) how much it was going to cost to paint the 210 I was told nothing south of $25,000. Add on the inevitable other bits and pieces that will crop up and you won't get any change out of $30k.

I'd certainly agree with that. The last one I had painted was a few years ago now and was getting up there. Stripping reveals a multitude of sins. I heard of one that had some hail damage that had been bogged probably decades ago. Not a word in the logs. The painter was was quite happy to rebog it ... for another 6 grand. I dread to think what is underneath some of those shiny paint jobs. Always better to buy one with original paint if you can.

But is painting really worth it? Let's say you have a 35 year old 172, with maybe 6,000 hours and mid life engine and prop. If it needs paint, probably needs interior too, and windows. The avionics are probably boat anchors. Then there's SIDs (painting would be a good time to do that.) Would look nice.... But would probably not see it for about 12 months and not be worth what it cost. Dont even think about the misery of project managing some of those morons who make promises they know they will not keep. Better decision is more likely parting out or paint on most of those old planes.

[Ultralights]

I'd certainly agree with that. The last one I had painted was a few years ago now and was getting up there. Stripping reveals a multitude of sins. I heard of one that had some hail damage that had been bogged probably decades ago. Not a word in the logs. The painter was was quite happy to rebog it ... for another 6 grand. I dread to think what is underneath some of those shiny paint jobs.

i know of a few B747-4**s' getting around carrying a few tonnes of Bog. :eek:

[Old Akro]

I called in to see Keith at Aeropaint a couple of weeks ago. He's going strong!

The repaint issue depends a bit on your objective. The Lance that Keith repainted for us cost about $40k including a single piece windscreen and some other speed mods, but we picked up a real 8 knots. A lot of the time (and money) was in fibreglass work. The wavy fibreglass components like wigtips take a lot of sanding hours to make nice and smooth. We took it back to bare metal and dealt with some corrosion issues & replaced some working rivets. We also replaced every exposed nut bot and screw. But at the end of it, we got an airframe that I have equal confidence in as a new one together with a paint job that still looks new 5 years later.

The other end of the spectrum is to rub the gloss off the existing paint and put another coat on the top. There are some guys who argue that this is better because it is less invasive.

[185skywagon]

Just putting the 185 through a thorough strip and repaint as we speak. Last paint turns out to have been done well in terms of preparation.
Phew.

I am expecting $20-30k, but how long is a piece of string....