Deburring edges

[PapaBravo]

Hello everyone,
I just found this link on Van's site and I just bookmarked it. I think this site will be great.

OK on to the question I have. I am currently working on my wings and I have been deburring the edges of the ribs and spars. I am running 400 grit sandpaper over the flange edges and the edges of the lightening holes in the webs until they are as smooth as possible. I will be alodining and priming with AKZO. I am figuring that the smother the part the odds of a possible future stress fracture ( from vibration) are reduced. How much of this is needed? Is it needed? Am I overworking?

Does anyone have any experience with this? To what extent are you deburring the edges? Do you leave them the way they are and not worry about them or do you smooth them?
Thanks

[Akroguy]

Use whatever means you find easy to use to break the edges. If you can run a finger along the edge without cutting yourself, it's good to go. That's my test....no blood=airworthy!

Worked on my RV8, which now has 5 years of flying behind it and not a single crack anywhere on the airframe. Basically, don't obsess over it, render the part safe to handle during assembly and it will be fine. Think about the masses of aircraft builders during WWII. I seriously doubt they spent much if any time polishing sheet metal edges.

Brian

[RV6junkie]

I used two tools for deburring; a "V" nosed deburing tool and a swiveling head speed deburing tool. Sandpaper works too, but the above tools work very fast and never wear out.

[darrylDog2000]

Two things I've never witnessed:

Two guys talking over an experimental airplane.
Guy A - "Wow, what a beautiful plane and look at that nose art."
Guy 2 - "Man, the talent it must take to build something like this."
Guy A - "And would you look at the smooth edges on those ribs, incredible!"

NTSB Report - Cause of accident - Structural failure due to using 400 grit sandpaper instead of 600 on rib flanges.