Good polish

[mulwyk]

Just wanted to pass on a little tip from my IA. He's a biker (Harley-Davidson fan) and he uses a polish on his bike called "Mother's Aluminum and Mag" polish. (He has the aluminum parts of his Harley polished up so they look like chrome) I'd been trying to polish my propeller with Rolite, an expensive "aircraft" polish. Jerry (the IA) suggested I try using Mothers.

Well, this weekend I got a can and tried it on the prop. Works great. It's a white paste that turns black in contact with the aluminum. I don't quite have the super shine that I'm after yet, but this stuff did more in a few minutes than the Rolite did in hours of rubbing. Best part is the price...$3.95 at Walmart.

[astjp2]

Re: Good polish

Be careful, most of those polishes are corrosive, if you read the techy stuff from the prop OME's, polishing is not approved....Tim

[Guest]

Re: Good polish

Tim's right polished props have been issues in the past and I also understand that the manufacturer does not approve, therefore you will render your prop unairworthy. Check with the manufacturer to be sure.

[mulwyk]

Re: Good polish

Wow. A $2000 prop ruined! What's the matter with my IA? Why didn't he tell me that? I'm pissed as hell!

Thanks for the warning, guys.

Oh well, I was leaning towards a wood prop anyway. I'm gonna have to throw that dam aluminum POS out in the weeds.

Anyone wanna buy a nice wall decoration?

[Larry Lyons]

Re: Good polish

I will wait for Forrest to weigh in here. I believe he told me that one of the things to do for max cruise was to polish your prop. There are a lot of War birds out there with out of cert. props!
Larry

[jstall]

Re: Good polish

Also

Nuvite, comes in several grit grades, and is absolutely the best I've seen for
polished AL on aircraft, we use it on the Cessna 190 and on Sweet and Lovely Bakers P-51D,

Grade C, first then Grade S for finish, way better than Metall, and some
better than Flitz, however Flitz is a good product also

Don't use "NEVER DULL" NOT GOOD IN MY OPINION, the steel wool hard on
the aluminum surface

[astjp2]

Re: Good polish

I will wait for Forrest to weigh in here. I believe he told me that one of the things to do for max cruise was to polish your prop. There are a lot of War birds out there with out of cert. props!
Larry

Warbirds were never certified with a TC, so they are form of experimental/exhibition. So the same rules do not apply to our aircraft.

[N95334]

Re: Good polish

Bob
Throw that polished prop my way if you do not want it. Let us get real here people. Wonder how many centuries it would take to polish that alum prop to a point it would be weak. Remember we are talking 65 hp 2300-rpm not super critical super sonic stuff we are working here.

[astjp2]

Re: Good polish

Well if the FAA ever wanted to, they could walk up to an airplane that had an airworthiness cert. and if they find ANYTHING, they can ground the aircraft and violate any pilot that flies it after its grounded. It has happened before. Tim

[Marv]

Re: Good polish

There is so many old aircraft flying, with polished props, i would not worry about it untill and if someone with authority did ground it. Marv

[fearofpavement]

Re: Good polish

I agree with the previous poster, I would not worry about it. I have been involved in aviation full time for over 30 years as a pilot and mechanic and have never heard before now that there is an issue with polishing a prop. (I always learn something on this forum) Anyway, I am just saying that I don't think that rules about prop polishing are very well understood and thus aren't likely to raise any issues. I am having a hard time trying to understand how it could hurt a propellor... If you were going to repaint it wouldn't you be doing a thorough job if you removed all the old paint and cleaned it up really well before applying the new paint? So if anyone officially says anything you can be in the process of refinishing it.

On another note, if anyone has any rules regarding polishing props they could point me to I would be interested in reading them and perhaps understanding why this is an issue.

[astjp2]

Re: Good polish

Its not an issue repainting because an overhaul shop would normally allodine the aluminum prior to painting. Where there is an issue is when you have a microscopic bit of corrision and you get a small rock ding. That is when you might get a stress riser and stress corrosion cracking. Personally I am not that anal but I just wanted to make people aware. Also the paint will take a lot of the abuse from small sand and gravel dings and not hurt the base metal

[hangarb7]

Re: Good polish

And just a final note on the polish itself.

Mother's worked for you because it is a pretty coarse grade and works well on items that need a lot of work or have never been polished. On the other end of the spectrum is Rolite. It is a great polish IF the surface has been polished before or just has some cloudiness. Mother's leaves terrible scuffs on Alclad aluminum.

As an owner of a polished aluminum airplane, the earlier suggestion for Nuvite is the only thing that I would consider on fuselage aluminum. Start with the coarse grades and move up to the cream. It is truly the most amazing material and safe for structural aluminum.

A few years ago I figured that I would go around Oshkosh and talk to the people who had the most beautiful polished airplanes to see what they used. The twin Beech I saw being polished on the flight line was awesome. They used Nuvite, so I do now. The fact that the gal polishing it was absolutely one of the most beautiful women I have ever met had nothing to do with it...

Jack D
N44057

[dmcneil]

Re: Good polish

Hey All,

There is an FAA Adivisory Circular that briefly touches on the polished prop question. Here's an excerpt:

AC 20-37E

Date: 9/9/05

AIRCRAFT PROPELLER MAINTENANCE

Chapter 2

205. Limitations

e. Blade Polishing. The FAA receives frequent inquiries from airplane owners and maintenance personnel asking whether it is acceptable to polish propeller blades. It is almost always not acceptable. Corrosion protection such as paint and anodize should not be removed from the surface of a propeller blade. Propeller blades must be maintained to the type design. If the original design had corrosion protection and the instructions for continued airworthiness call for corrosion protection, then the corrosion protection should be maintained to those instructions.

So, the FAA starts out with the notion that polishing props is a bad idea. There are manufacturers that have prop polishing procedures in their overhaul manuals... Hamilton Standard and Curtiss Reid come to mind. There may be others. The original overhaul manual for the McCauley 1A90 and 1B90 props does not mention polishing.... not sure about the fixed pitch Sensenich. If it isn't specifically mentioned in the overhaul manual, the FAA has taken the position it is prohibited. Because of this, prop shops will not polish most props.

A few years ago, a couple of airplanes with polished props were grounded by one particular inspector in the San Francisco Bay Area. It can happen.

Dan

p.s. Nuvite is the only polish worth using. It's just superior to any of the others. Jack D, are you sure the airplane you saw being polihed was a Beech 18? Kent and Sandy Blankenburg have a highly polished Lockheed 12A and Sandy is a real babe!

[hangarb7]

Re: Good polish

Hi Dan,

I am sure you are correct. I did some googling on Kent and Sandy and they apparently are not only owners of a Lockheed, but also a polished Spartan Exec and a polished Luscombe. She is stunning. (You pick which one I mean

Absolutely agreed on the Nuvite. It is expensive but worth every penny.

Thanks for the correction!

Jack