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A few days ago when I finished preparing the parts for the brake pedals, I decided not to prime or paint them or rivet them together just yet, thinking I would consider options about colors for paint, what the interior of my cabin will look like, etc. I've been giving these considerations a lot of thought, but I haven't made any decisions yet. Then, I was looking at my wing spars. They're hard-anodized in a beautiful gold color. They're gorgeous. And I know from all the experience I have when I built my wings just how durable and hard the anodized aluminum is. Then it occurred to me that I have flashlights and other common items that are made of anodized aluminum. They keep a beautiful appearance for a very long time despite everyday use and abuse. So I decided, why not look into having my brake pedals anodized? Surely it wouldn't cost much for a few little parts. And my hunch is, it will be tougher and last longer than paint. It doesn't add any weight. I think I recall even seeing an example or two online over the last year or two, of other builders who have chosen to have parts anodized. I thought of having them powdercoated, too. But I wanted to check this out first.

What is anodizing, anyway? Well, I learned that anodizing is not the same thing as metal plating. It's not a coating, either. You're not adding a layer of anything to the metal. You're chemically changing it. It's an electrolytic process for producing controlled aluminum oxide films on aluminum. The electrochemical process both thickens and strengthens the naturally-occurring oxide. The resulting finish is extremely hard and exceptionally wear resistant, according to what I read. I didn't realize that you can get aluminum anodized in a rainbow of different colors!

A quick google search turned up roughly a dozen anodizing shops here in my city. Wow! I had no idea there were so many. So I grabbed all the brake pedal parts and went to the closest one, about 5 min. away, to check into it. They have a minimum shop fee of $50, as it turns out, so I prepared to leave. But the guy lowered the price and gave me a 20% discount. In retrospect, I think the best thing would be for two or three builders to go together on a batch of parts and split the cost. That would make it even more reasonable. Anyway, the company I went with is called Apex Anodizing http://www.apexanodizing.com/ if you're interested. They also have a shop in Nevada. The district manager, Jim Malnar, was very nice, helpful, and totally committed to my satisfaction. I was impressed that a small one-time customer like me would get this kind of attention from high level management.

I decided to go with the Bright Dip Fiery Red color and to have the anodizing done before riveting, so the rivets would show and contrast with the color. I really like the brassy look of the flush rivets next to this color. They're the same color as the AN-3 bolts and nuts used for the hardware. The color of the master cylinders matches the hardware and rivets, too. It's a perfect match.



After a couple of days, they were ready. I was so excited about how gorgeous the parts looked, that I set to work immediately when I got home and riveted them all together. These rivets can all be squeezed easily. Here's another close-up shot:



Tonight was our monthly Chapter 105 meeting. I finished these up just in time before heading out the door, so I took them with me for a little show-and-tell. Once a year, our chapter has one of our regular monthly meetings at Van's Aircraft. It's always one of the most popular meetings of the year. The factory is open for a walk-through tour, an update from some of the staff on what's going on at Vans, a few words of wisdom from Van, and time to hang out in the hanger and look at all the planes. To top it off, Vans provides pizza and sodas for everyone. How can you beat that? A good number of planes flew in for the event, too. We had over 80 people attend. I had fun passing these around. I got a lot of very nice comments and compliments, including one from Van himself.

Well, when I got back home, I just had to see what these pedals will look like mounted in place on the rudder pedals. Here they are, ready to go:

Bruce, those are freakin' AWESOME, and I am INSANELY jealous!!!

That looks really nice. Wonder how you could then add some type of texture to them for grip.

Bruce - Looks great!!

Just a word of caution for others though.. annodizing aluminum affects the fatique life (and not in a good way)!
Don't even consider it for stressed parts.

Here's the tragic example of what can happen:
http://www.experimentalhelo.com/Anodizing&Fatigue.pdf

Lorin D

So what does that mean for our spars that pretty much 100% of them have cracks in the anodizing radiating out from most of the rivets we set?

Bruce, I like them so much that you now have me contemplating the purchase of a new set of rudder pedals.

Thanks, Chad! I knew you would like them. I went back and looked at yours. They look very similar. These might be a bit darker in color. Hard to tell unless you got them in the same light. After all the trouble you went to to strip powder coating and re-do those parts, it wouldn't take much to strip your brake pedals if you want to redo them. Or, the parts are cheap enough to get new ones and do them this way. Then you would have a spare set on hand.

Spike, I think if you really needed it, you could always add some strips of wing-walk stick-on tape. Or, rough them up before you have them anodized.

Lorin, Thanks for the article. I read through it. Some caution is well noted before doing anything that strays from the plans. They don't mention what alloy was used for the helicopter in question, so I'm wondering about that. And Kelly made a good point... then what about our wing spars? They are certainly the most critical structural stressed parts in the whole airplane. I drilled some of the holes in my brake pedals after the anodizing, so I know the anodizing is very thin. It's a microscopic surface layer.

Thanks, Brad!

BSwayze wrote:And Kelly made a good point... then what about our wing spars? They are certainly the most critical structural stressed parts in the whole airplane.

I seem to recall this being discussed somewhere before and IIRC the concensus was that Van's has taken this into account when designing the spars.

I used to fret about this too. Then the issue came up on The Other Site a few years back, and a quote surfaced from Van about the fatigue strength of an anodized spar. I think you'll find it somewhere in the RVator.

According to Van, anodized wing spars subjected to 100 hours a year of hard aerobatics (+6/-4G loads) have a fatigue life of 80 years.

After that, I stopped fretting about anodized spars.

Hope this helps,

Dave