New Paint any noticeable airspeed increase, weight saving?

[Brian2034]

Trying to decide if I want to go through the strip, prep and paint process!

Or maybe just a prep (sand and scuff) and paint?

Any evidence that paint increases speed or does new paint just look faster!

also opinions on a complete strip and paint or a scuff and paint.

On my Mooney the paint is worn not flaking or peeling, I’m really contemplating just a scuff and paint, the striping process is the worst part of the paint work.

I’ve did a few strip and paint jobs and I’m not convinced it’s really worth the work.

Also I don’t think there’s much of a weight savings if your striping a aircraft with worn thin paint.

 

[jetdriven]

To do it right you need to strip it and acid etch it and alodine it and then prime it with some epoxy primer and then paint it. Think about this, if you’re gonna scuff it and paint over what’s already there,  you’re betting that’s gonna hold onto the metal but that paint job may be 30 years old. The paint shop is not going to warranty it. If you don’t wet sand the previous stripes, you will see those through the new top coat. And if you’re gonna spend enough time to knock all the edges off the stripes, that costs real money too l…it comes out of the savings that you saved from not stripping it. And how much are you really saving? Two or 3K? Is it really worth it?  

[Fritz1]

no speed gain or weight savings, I had a G-model painted by now defunct Mod Works in 2000 and I had to twist their arm not to strip it, the paint was just worn, nothing was flaking, no adherence problem, that airplane still flies today with the same paint job and looks good, nothing coming off, you are limited to the original graphics though, when I had the Bravo painted in 2018 I did not have that option, paint was coming off in lots of places partially due the TKS fluid creeping under the paint, bottom line if your paint is not chipping off, not stripping is an option, why disturb primer that has been on there doing its job for 30 or 40 years

[Hank]

Cleaning and waxing your Mooney will make it faster. The slicker the surface, the faster you will go.

[bigmo]

5 minutes ago, Hank said:

Cleaning and waxing your Mooneybwill make it faster. The slicker the surface, the faster you will go.

This is no joke. I’ll do it this winter, but with my last a/c I had a car detailer clean, buff, and apply a ceramic coating. I knew my cruise math well and it picked up a solid 4 knots. It wasn’t cheap, but it sure made summer bug cleanup easy.

[jetdriven]

1 hour ago, Fritz1 said:

no speed gain or weight savings, I had a G-model painted by now defunct Mod Works in 2000 and I had to twist their arm not to strip it, the paint was just worn, nothing was flaking, no adherence problem, that airplane still flies today with the same paint job and looks good, nothing coming off, you are limited to the original graphics though, when I had the Bravo painted in 2018 I did not have that option, paint was coming off in lots of places partially due the TKS fluid creeping under the paint, bottom line if your paint is not chipping off, not stripping is an option, why disturb primer that has been on there doing its job for 30 or 40 years

Because it’s been on there for 30 or 40 years. 

[Brian2034]

This is not my first repaint

I’ve stripped and repainted three planes in the last 3 years, I’m just not sure it’s worth the labour to completely strip to repaint. 
If the existing paint is in good shape but worn thin, I’m thinking a clean up and repaint will work.

[Brian2034]

And yes they where strip, alumaprep, alodine, prime and paint.

The strip is the time consuming and evil part of the process!!!

[KSMooniac]

Paint is heavy, so it should be stripped before a new paint job.

Sent from my motorola edge plus 2023 using Tapatalk

[McMooney]

4 hours ago, Hank said:

Cleaning and waxing your Mooneybwill make it faster. The slicker the surface, the faster you will go.

this is absolutely true, birdy would fly 5kts faster when washed and waxed.    paints so bad now, wa

[McMooney]

I"m really hoping to sand / co2 blast birdy, epoxy prime and  paint,  I don't want those chemicals anywhere near her.

 

[A64Pilot]

I won’t say too much about speed increases personally I haven’t seen as much as others.

There are pros and cons, paint is indeed heavier than you may suspect, but stripping involves chemicals that wicks into metal where it overlaps and into rivet holes, it’s extremely caustic stuff as it eats paint, well it eats aluminum too so any aircraft that’s been stripped will have corrosion from the stripping, but sometimes you have no choice, if the underlining layer is breaking up then of course an overspray will too.

Then all flight controls have to be rebalanced especially for those that weren’t stripped. Stripping you might get lucky and end up where you started but as the area of a flight control aft of the hinge line is much greater than that fwd of it, you will gain considerable weight that has to be counterbalanced, often the weight required to balance tge control exceeds max allowable, then you have to strip and start over.

At the Boeing Apache plant in Mesa Arizona they had a machine that had a head that hit the paint with unbelievably strong UV light then blasted it with CO2 pellets to remove it, it was precise enough that it could strip down to primer but leave the primer, I saw it working, but it was an apparently millions of dollars robot. I didn’t know that was available in the civilian world, but if it is that would be the way to go.

https://boeing.mediaroom.com/1998-06-12-FLASHJET-Paint-Removal-Systems-Completes-Fiftieth-Apache-Fuselage

But yes the disassembly and stripping etc is the most labor intensive part of painting an aircraft. Once the prep is done the painting is the quick part.

Edited November 12 by A64Pilot

[Pinecone]

8 hours ago, KSMooniac said:

Paint is heavy, so it should be stripped before a new paint job.

I recall seeing something about why American did not paint their planes in the past.  The savings was hundreds of pounds for the paint.

[A64Pilot]

Boeing issued a ltr years ago, maybe the 70’s that laid out how much fuel was consumed over the life of a painted aircraft vs one that wasn’t and it was a HUGE number.

However unpainted surfaces have to be polished occasionally and if memory serves that labor costs wipes out the fuel savings.

This is from memory so I could be wrong

[Fritz1]

As A64 said the stripper is the problem, under no circumstances must that stuff be vaporized, applying by hand and staying away from seams and carefully removing by hand is extremely time consuming, at the MBB military aircraft shop in Manching Bavaria we had a CO2 blasting apparatus, worked very well but prohibitively expensive for small aircraft, when I had the Bravo painted I insisted that the stripper not be vaporized, hard to tell if they did or not, paint shop better be visited at least once a week to see what is going on, good paint work is hard to come by because it is hard and extremely labor intensive

[KSMooniac]

We re-weighed my plane last month after some extensive mods to include a full paint job (final step in my hail repair/upgrade sequence).  I gained ~80 lbs over the book numbers, and at least half of that is the paint job IMO.  I think today's paint with "friendlier" chemical compositions and higher amounts of solids are quite a bit heavier than what was applied in the early days and likely through the 80's.  Doing metallics or other systems with base + clear coat make it even worse, too.  The rest of my weight gain can be attributed to the later overhead vent system, SoundEx insulation, and a full set of Bravo seats (2x articulating fronts, removable buckets in back) with memory foam inside and headrests.  

[jetdriven]

9 hours ago, Fritz1 said:

As A64 said the stripper is the problem, under no circumstances must that stuff be vaporized, applying by hand and staying away from seams and carefully removing by hand is extremely time consuming, at the MBB military aircraft shop in Manching Bavaria we had a CO2 blasting apparatus, worked very well but prohibitively expensive for small aircraft, when I had the Bravo painted I insisted that the stripper not be vaporized, hard to tell if they did or not, paint shop better be visited at least once a week to see what is going on, good paint work is hard to come by because it is hard and extremely labor intensive

We’ve been stripping airplanes for 90 years now. The newest stripper is actually a benzyl alcohol/peroxide stripper and when you rinse it with water it neutralizes it. And then when you put acid on there, it removes the rest of it. And then you rinse that off and then you alodine it And as long as everything is rinsed properly, you don’t get filiform corrosion. It’s fine. It’s industry standard. I’ve done a lot of small parts with prekote but I haven’t done a whole plane, but I think that’s probably fine too and it’s a lot less toxic.

[A64Pilot]

Prekote is a treatment meant largely to replace Cadmium plating and not any kind of stripping? I’m not impressed with it, sure it’s a lot better than nothing but it’s not as good as Cadmium plating, not even close. Thrush went to it in the last year or so that I was there for wing spars as a cost saving. I wasn’t a fan. It is easy and apparently environmentally friendly.

Glad to hear that there are safe strippers, but gut says they aren’t as effective, require more work and success is largely dependent on the worker knowing what they are doing and following directions. I bet very often that “Aircraft paint stripper” is bought from auto paint stores, you know the stuff that oddly says on it “not to be used on aircraft” I’m sure like most everything else if done right it’s not that destructive, but if it’s not it’s is.

Me personally if shopping I’d rather have an airplane with original paint. Mine unfortunately had been repainted, not very well either, but finding the perfect airplane is rare

[jetdriven]

Prekote is supposed to replace the acid etch and alodine .  Where it’s really valuable is magnesium.   They used to sell a chemical called Magnadyne, which was like Alodine for magnesium.  But it hasn’t been made in years, and alodine is for aluminum.  It doesn’t work on magnesium.  Paint shops either don’t know this or pretend it doesn’t matter. But it’s a recipe for filiform corrosion for magnesium.  However, Prekote seems to hold up for a decade, as the wheels on my plane have been painted that long.