It is really important to remove the burrs that are created when drilling through aluminum prior to riveting. Otherwise the rivets will not get a good, strong grip and will work loose over time. The rivets shown here were at the top of a lift strut. Definitely not a good place to skimp on deburring!
So how do you debur the inside of tubing, such as lift struts, or the tubular spars found in many light sport kit planes?
Cogsdill company (Cogsdill.com), makes a series of deburring tools for one pass deburring of both sides of a hole, even a blind hole in a tube. The tools are sized for each diameter hole. They are not cheap, $50-$60 bucks a piece the last time I checked. Perhaps a good item for a chapter toolkit. They even make specialized bits with different rake angles for steel and aluminum.
Bill, Thanks! I’ll look into those.
Thanks for posting about the cogdill drills. I have a number of them in various sizes. They work wonderfully.