Polishing a Hartzel Prop

[SHORTRV7]

I am starting to reserch the idea of polishing a Hartzel CS Prop. Years ago I owned a beautiful Globe Swift with a CS poslished Prop. Just looking for thoughts hear.
Don

[RV8N]

If its a new prop it will void the warranty. I really like the look but its not worth it to me.

Karl

[gmcjetpilot]

Originally Posted by SHORTRV7

I am starting to research the idea of polishing a Hartzell CS Prop. Years ago I owned a beautiful Globe Swift with a CS polished Prop. Just looking for thoughts hear.
Don

Not sure about warranty, but I believe American Propeller in North California can do it or even do custom paint jobs, and is a Hartzell repair station. I am pretty sure you can polish and clear coat or clear anodize safely and not damage it. (click on designer*prop)

http://www.americanpropeller.com/facilitypropeller.htm


My RV-4 was done this way, polished, with pearl in the clear. It looked good and did not need polishing. The back of the blades where painted flat black.

[John Clark]

Not a good plan. Advisory Circular AC 20-37E is very clear, "don't do it."
And yes, it looks great, but not worth the risk.

John Clark
RV8 N18U "Sunshine"
KSBA

[rv72004]

Why is polishing a prop a bad idea ? Just curious as I see the only downside being the upkeep factor. Then again what I know about props is dangerous.EJ

[Kahuna]

Sections of AC 20-37E
......
Surface Corrosion. The loss of surface metal due to chemical or electro-chemical action with visible oxidation products usually having a contrasting color and texture to the base metal. Surface corrosion, as shown in Figures 1-1 and 1-2, generally results when the corrosion protection on a metal surface has been removed by erosion or by polishing. Therefore, removing paint and corrosion protection, such as when polishing blades, is not recommended.
.......
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.
........
(8) Do not polish blades unless specifically permitted by the manufacturer?s instructions.
........
Corrosion, Surface. Surface loss of metal due to chemical or electro-chemical action. On polished surfaces begins as a dulling of surface, soon becoming frosted, followed by widespread pitting.

[gmcjetpilot]

Originally Posted by Kahuna

Sections of AC 20-37E......removing paint and corrosion protection, such as when polishing blades, is not recommended.


e. Blade Polishing. Propeller blades must be maintained to the type design.

Type design does not apply to experimental, but the caution is valid. Corrosion? An experimental is likely to be pampered hanger queen. Two, there are clear coats that you can use over the polish. Also if you truly polish it, with wax and maintain that, corrosion should not be an issue, especially with a hangered plane flown frequently.

Erosion in flight from dust and rain and over polishing would be my concern. You could reduce the life of the blades.

Clear alodine/clear coat looks awesome. Its not polished but polished is lots of work. Regardless paint the back side of the blades with flat black paint is what I would do. The leading edge and back of the blades take a beating. Its better to have a hard coat of paint on back. The leading edge is hard to protect. Even factory finishes don't last.

[SHORTRV7]

Thanks for your responses, like I said, I owned a Swift with a polished prop and it was absolutly not a problem to maintain it ---- But all of the possible damage, warrenty issues does concern me, so I will have to give it some more thought. The Swift came with the prop, now I have to buy one $$$$$$$.
Thanks,
Don