Kenneth
Member
I ran into an issue recently where I had to drill out the rivets that attach a leading edge rib to the wing spar. Unfortunately for me, I did the "right" thing when I originally assembled it and used CherryMax structural rivets with the manufactured head *inside* the leading edge. This meant that I could only access the rivet from the shop head on the aft side of the wing spar.
After a couple of unsuccessful attempts at drilling out a rivet free hand, I figured there had to be a better way.
I got the idea of using a hardened steel drill bushing that fit over the shop head and the matching drill bit to remove the shop head to nearly the spar, then punching it through with a punch. This method worked perfectly.
In my case the shop heads measured between .163" and .165". I found a .166" (#19) ID x 1/2" long drill bushing on McMaster-Carr's Website part #8492A022. It cost me about $10. I also ordered a long #19 drill bit to fit inside the bushing.
I then held the bushing over the shop head, perpendicular to the spar web and inserted the drill bit in the bushing and slowly removed material until there was about 1/64" of rivet material remaining outside the spar. At that point, I could just use a #30 punch to remove the rivet.
This method ended up taking very little time and worked great for the uniformly sized CherryMax rivet shop heads. I'd expect you'd get similar results from squeezed or properly shot solid rivets.
Good luck!
--Ken
After a couple of unsuccessful attempts at drilling out a rivet free hand, I figured there had to be a better way.
I got the idea of using a hardened steel drill bushing that fit over the shop head and the matching drill bit to remove the shop head to nearly the spar, then punching it through with a punch. This method worked perfectly.
In my case the shop heads measured between .163" and .165". I found a .166" (#19) ID x 1/2" long drill bushing on McMaster-Carr's Website part #8492A022. It cost me about $10. I also ordered a long #19 drill bit to fit inside the bushing.
I then held the bushing over the shop head, perpendicular to the spar web and inserted the drill bit in the bushing and slowly removed material until there was about 1/64" of rivet material remaining outside the spar. At that point, I could just use a #30 punch to remove the rivet.
This method ended up taking very little time and worked great for the uniformly sized CherryMax rivet shop heads. I'd expect you'd get similar results from squeezed or properly shot solid rivets.
Good luck!
--Ken
