Page 11 - Volume 11 Number 12

Things to Ponder When
Considering a New Paint Job
by Dean Benedict, A&P, AI
Thinking of having your King Air painted? No doubt the first thing that comes to mind is the cost. New paint is pricey, and you’ll want to shop around. For a 90 series King Air you could see quotes ranging from $25,000 to $50,000, or more. With bigger aircraft and custom paint schemes, it only goes up from there.
Before you start salivating over paint colors and design, you need to get down to the nitty-gritty. Get several quotes, which may vary immensely in price and what it covers. You’re going to have to dig into the quotes to get an apples-to-apples comparison.
Comparing Quotes
First off, determine what exactly is being stripped and painted. Are they painting the gear? What about the wheel wells and flap wells? Do they pressure wash and paint over certain areas or do they strip and paint everything? You need to know.
How much time do they allow for a basic paint job on your type of aircraft? Does the quote detail the preparation steps and materials used? You don’t want a shop that cuts corners, and you don’t want to be taken to the cleaners.
I’ve seen a lot of King Airs in my day – some with great paint, others not so much. Below, are a few topics for you to keep in mind regarding a new paint job.
Stripping
A King Air will always be stripped before repainting. This can be done with media blast (such as glass beads or walnut shell particles), chemical strippers, or in
certain circumstances, sanding. Chemical strippers are the most common choice.
Careful masking of everything not being stripped and painted is just one of the time-consuming parts of the job. Chemical strippers destroy plastic and rubber. Windows, light lenses, beacons, boots, seals and tires will be ruined if they come in contact with stripper. Antennas have a protective coating that is destroyed by strippers. All these items must be well protected.
Chemical strippers are highly corrosive, so they must be cleaned off after they’ve done their job. Close attention must be paid to getting stripper out of every crack and crevice where it may have seeped, such as skin laps and inspection panels.
I recently heard about a B200 with a lot of problems following the installation of a G-1000 panel. They double- checked and triple-checked everything to no avail. A great deal of time was spent chasing the problems. Ultimately, they found corroded skin under the antennas, and guess what? That airplane had been recently painted. Apparently, stripper seeped into the antenna bases and compromised their bond. Careful masking should have prevented this.
Prep and Prime
After stripping and cleaning, bare aluminum needs protection against corrosion. For decades, zinc chromate primer, that ubiquitous yellow-green coating found on the innards of every airplane, was the way to go. When chromates were deemed a health hazard, zinc phosphate became popular. It looks exactly like zinc chromate, so all
During the paint stripping process (left) and after all the paint has been stripped off (right).
DECEMBER 2017
KING AIR MAGAZINE • 9
MAINTENANCE TIP