Hardware choices

[alvinsager]

Hi gang,
95% done and 95% to go. I like to know where I am going long before I start out. I am getting the first of many final hardware list together. I need a little input as to whether to paint the exposed nuts and bolts or to use stainless. Today I am inclined to use stainless since wrenching will not mess up the paint if I went that way. My other bird that is kept outside showed that the standard cad plated bolts unpainted give in to rust at a couple or three years. My Hatz will enjoy a Hangar when not out being exercised. I have looked at lots of planes but never to check out hardware. Cowling hardware and screws will be stainless as well as the flying wires and fittings, so why am I asking a question that I already know the answer to. Are there any strength issues relating to stainless bolts?
Al

[M Lightsey]

Al,
I'm not a fan of stainless hardware. Cadmium is sacrificial to aluminum, but aluminum is sacrificial to stainless in cathodic terms. In other words if you use stainless fasteners on an aluminum structure, over time the aluminum will start to corrode. If you use cad plated steel fasteners, the cad plating will corrode but the aluminum will remain intact.
At the end of the day, which would you rather replace?
What's the point of having nice shiny hardware if your structure is turning to powder?
One of my customers a few years ago was really big on this having previously lived in Hawaii. I didn't really get it at the time. Since then, I've been involved with several planes that had spent time in warm humid environments. I get it now. It's no joke and happens quicker than you'd think.
My $0.02
Mark

[alvinsager]

Hi Mark,
That is exactly the information I was looking for. New Jersey has been known to be humid and near the coast also!
Thanks,
Al

[alvinsager]

While on the subject, are any details like thin plastic washers used under screws used to prevent breaking of the paint film (non structural).
Al

[M Lightsey]

Nylon washers are great, we get them from McMaster Carr. Even with washers though, you've got to go easy on new paint. Ranthane/Aerothane stay soft for quite a while, even though they're dry. Too much too soon and you'll twist a blister into the paint. Depending on temperature, it can take a couple of weeks or more for the paint to really harden up.
Mark

[alvinsager]

Thanks Mark, I know McMaster well, I am in their same day delivery radius and use them frequently. Definitely a place home builders should look to for hard to find items.