Aircraft painting advice anyone?

[Matthew_bailey]

My straight tail 172 paint stripping is coming along nicely. Wings, Horizontal stab, elevators, fin, rudder, upper & lower cowl, right door, and 80% of the fuselage are now stripped. I have to say this was more work than I had anticipated. So far I have gone through approximately 10 gal of paint stripper. 'Jasco' and 'Aircraft paint stripper' seem to work the best. Some types of paint stripper may cause aluminum embrittlement. It’s probably smart and legal to use a stripper designed for aircraft. There seems to have been about 4-5 different colors and possibly 3 types of primers applied since this aircraft was new. I now use a DA orbital sander with a 6" velcro pad to which I attach a 6" round red Scotchbrite pad. Leaves a really nice even finish after the paint is stripped off and is not harmful to rivet heads. The Scotchbrite works best when used with water. Pressure washer is necessary for final cleaning of stripper and after Scotchbrite. After a little sheet metal work and a few Bondo spots I think I will be ready to start painting. I want to do my own painting while the plane is completely disassembled. I have a good area to paint that will be completely enclosed in plastic and have ventilation fans. I am looking for any suggestions or advice on the type of primer and paint that I should consider and what I should do to prep/clean the aluminum. This is pretty much my first time painting, although my neighbor has painted his plane before and is willing to help. He painted his aircraft with Dupont Imron. I have a new HVLP gun and a good 60 gal stand up compressor with several water traps. Once I spray the primer do I need to spray the base color with in a certain time period? Is there a good source of info on the different types of paint I can choose from?

Regards,
Matt

[Tom Downey]

High pressure washers make me nervous, they force stripper under lap seams.
When you get all the paint off, before you mask any thing, take the aircraft to the wash rack and use "Aluma Prep" from Aircraft Spruce & Speciality and clean the whole aircraft, then alodine all the bare metal. Be sure to rinse and re rinse, then DO NOT touch any bare metal with your bare hands after that.
Use a good tack rag to wipe down just prior to spraying the primer. I always advise a novice to hire a local body shop painter to come shoot the color coat.
You have a lot of work involved, don't try to learn how to paint now.

[N170BP]

An alternative to using aluminum etch & alodine prior to prime, is to
use a self etching primer like Variprime. Variprime is nasty stuff,
so you need the proper equipment to protect your lungs & skin (the
bad stuff can get into your system through your skin and through your
eyeballs, not to mention your lungs).

I'm not the tree hugging type, but that etch & alodine (contains
chromium) has to go somewhere if you apply it to the whole airplane
and rinse/wash it of.... (like in down the drain!).

Bela P. Havasreti
'54 C-170B N170BP

[Tom Downey]

I don't much care for Chromic acid also, but any one repainting an aircraft should read and understand chapter 6 of the AC 43,13-1b. It could mean the difference between a great paint job and corrosion repairs that could cost more than the aircraft is worth. Veri prime is a good product, but it is a poor subsitute for etch and alodine.

[funseventy]

I would etch and alodine and use variprime. I had a bad spot on the fuselage of my Swift a number of years back. I prepped and primed it with Variprime then shot the color. I was never happy with the match so I sent the airplane out for paint. I went to check on it when they were done stripping, WOW! The airplane was clean and shiny everywhere except where I used Variprime. It was still green/tan and looked perfect. They had to sand it off. No that's some good primer! DP40 is my next preference but since they changed it to lead-free it is not as good. Pro painters will tell you that you should have the same Pro shoot the primer if you plan on using a pro for the color. Any error in the primer will show in the color.

That's about 1 cent worth,
Kelly

[Dave Clark]

Tom is right about using the acid wash and alodine. Wash primers just are not the same. DP40 is still a great primer for under urethanes. Lead based paint is for steel, zinc chromates for aluminum. Remember to follow instructions on recoat time with the epoxy based primers. Or any primers topcoats for that matter. Especially for the beginner read the instructions carefully and try to stay with one manufacturer throughout to insure compatability of all primers and topcoats.

PPG and other paints and a wealth of information is available online at
autobodydepot.net

[Matthew_bailey]

Any one care to hazard a guess as to how much AlumaPrep and Alodine I should order to prep the entire bird?

[doakes]

Matt,
I painted my bird using Emron and the grey epoxy primer. I followed Dupont instructions and had no problems. The final paint color had to be sprayed I think within 24 hours of the primer or you have to sand the primer. I did that, did not want to work harder, and it looks nice today.
I bought all my paint and pre-paint products from a local auto paint store.
I think that you will need 2 gal each of the Alodine and wash, don't hold me to that
I hired a paint man to shoot the final also. However he was not reliable and I had to do part of it myself. If you have never done it before, get some metal, and paint a scrape piece first. It will be worth it, as I found that my paint gun was not expensive enough and had to but a better one.
Do not experiment on your airplane, you've got too much work for trial and error.
If you use Emron be sure to use a fresh air system to breath. You don't want to chance cancer later in life.
I bought Jeppesen's book on Aircraft Painting and Finishing. It was a real help too.
I hope you the best,
Dave

[wa4jr]

I'm now looking at getting rid of the "Billy Bob" paint job on my machine. After reading the research on commercial paint jobs on another thread and hearing of the quality variation and ungodly high prices, I'm considering doing this job myself. The advice on this thread is somewhat dated so I thought I'd ask if anyone has any recent experience/advice? I've painted a few cars with PPG products and it just isn't that hard if proper prep work is done. My main worry about aircraft painting is the extremely large surface area. With a car, I can get around the whole job in a matter of minutes so that the entire project remains tacky minimizing the danger of overspray. I worry that getting around an airplane before the paint "skins", taking care to keep the airhose from tangling and fowling newly painted areas might be quite difficult. For those of you that have painted your aircraft, do you paint the underside of the wings first, then move around the leading edge to the top and then move on to the fuselage? What is the best type of masking tape to use during stripping and painting? I worry about stripper leaching under the tape along my windows and doing a real nasty job

Uhoh, I've almost talked myself into checking out current prices at some local paint shops...but then I just have a hard time justifying such an expense when the whole airplane is not worth much over $40K. Is shelling out 25% of the value of the aircraft for a paint job sensible or am I just a cheap SOB?

[GAHorn]

Is shelling out 25% of the value of the aircraft for a paint job sensible or am I just a cheap SOB?

Yes. And, yes.

You can save about 75% of the cost of a paint job by stripping the whole thing, then masking and painting only the part the factory did originally. The rest is polished.

[Joe Moilanen]

I know this sounds weird but the guy that painted my plane in 1984 (Max Robertson of Vancouver, WA) INSISTED on shooting Emron on bare aluminum without primer. I don't know exactly what the aluminum was prepped with but the paint job looks just as good today as the day it was painted over 22 years ago.

Joe
4518C

[wa4jr]

I suppose I'll make the "to polish or not to polish" decision once I have the aircraft stripped sometime next year. If the surface is in good condition I may go the polished route, but I fear that in many places the aluminium top layer may have worn away and I'd have unprotected alloy exposed to the elements

Hey Joe, where can I get a full size version of the 170 photo you have posted with your comment?

[bradbrady]

I know I'm going to ketch some flack here but in the question of is 25% of the value of the aircraft worth a paint job? I'd have to say lets put it more close to 50% IMO when you are ready to paint a 50+ year old airplane you better dissamble the entire A/C, It allows you to look at many items that couldn't be seen for that long, every A/C I've painted has had the wing mount blocks corroded to some extent, one 180 had a block so bad I had to replace it . Every bolt should be replaced. Legaly all control systems have to be ballanced after painting. (I have heard of feds seeing a apparently new paint job and looking at the bolts that attach the control surfacse seeing paint and grounding the A/C.) When you remove the tail and wings it also lets you see all the cables. And allows you to pull the bell cranks clean and paint them not to mention clean and regrease the bearrings that haven't seen new grease in 50 years! I think you all will get my drift!
brad