Firewall

[Jdm]

I’m redoing some electrical items on the this firewall. While I’m at it I’d like to get rid of the surface corrosion and polish out the firewall. I tried a small Scotch Brite pad soaked with WD40. Also tried it soaked with Corrosion X. Both methods seem work well but I don’t want to take too much material off or waste time if there’s a better approach. Any suggestions?

TIA

 

[kyleb]

What's the firewall made of? If it is galvanized steel, I wouldn't use abrasives or acids on it. Soap and water, yes. A solvent, yes. But nothing chemically reactive. Stainless? Knock yourself out. Abrasives, chemically reactive products, solvents...Whatever works.

 

[AlphaPilotFlyer]

Try different methods in small sports and mark with tape. Start less abrasive …. Find out what the material is , normally it’s stainless but check around. I found a car polish normally works well

 

[Bell206]

Any suggestions?

Are you talking about the hardware, rivets? The firewall looks like galvanized in pics so I wouldnt touch that at all except for a mild degreaser or aitcraft soap?

 

[Jdm]

It’s magnetic so I’m guessing it is galvanized. The rivets, hardware, and electrical components have some corrosion. I’m addressing that but was hoping to clean the firewall up a bit as well for better appearance. The small area I cleaned with scotch brite and wd40 looks great but I don’t want to take away any protection by overdoing it.

 

[Domenick]

If you insist on an abrasive, a blue scotch pad and Corrosion-X, followed by a wipe down with a Corrosion-X soaked cloth. You do not want to mar the galvanization. Corrosion-X states it shuts down the electrolysis which leads to corrosion even against existing corrosion. I'd trust it against the mild surface corrosion I can see in your photo, but not for something considerably deeper.

You may also consider replacing those steel screws with stainless.

 

[Bell206]

hoping to clean the firewall up a bit as well for better appearance.

Outside of a soap wipe down, beyond that you increase your risk of compromising the galvanize coating, which looks worse. If the hardware and rivets bother you, replace the hardware and wipe down the rivets with Corrosion X.

 

[Wagondriver]

With that much corrosion, what's the rest of the airframe look like?

 

[Jdm]

It’s not that much overall. Mostly just in that one area for some reason. I suspect the previous owner used to place a combustion heater in that area of the engine compartment, which caused overheating and lead to heavier corrosion over time. There is a light dusting of surface corrosion in the wings but only on the rivet heads, which can be easily treated. Fortunately the internal aluminum structure of the wings were zinc chromate from the factory and are still perfectly clean. The elevators were magnesium and neglected beyond repair. We STC’d the elevators to aluminum skins. Overall a very solid airframe.