To drill out or not to drill out...that is the question

Chris flies · #1 08-08-2008, 03:12 PM

Regarding the horn brace for a 7a rudder. Squeezed 3 universal rivets (flange) with the squeezer not perpendicular resulting in 3 shop heads which are oval shape. I have been proud of my rivets so far. Any how...the Tech councilor said to drill em out but Vans said to "build on." I've drilled out rivets before but gotta to admit haven't nailed down the technique to 90% success and I've seen so many ugly holes on the web resulting from drilling out rivets that went bad. I figure they may not be pretty but according to Vans they are sound. I am leaning on just leaving them. Any opinions appreciated.

danielhv · #2 08-08-2008, 03:48 PM

I'd drill em out... only because the horn brace is thick, and it would be kinda difficult to mess up the holes. I'll give you a tip that works well for me... I use a pretty small drill bit, much smaller than the #40. And drill a "pilot" hole through the center of the manufactured head... then I'll enlarge it to whatever size punch I'm using to pull the head off. Doing it this way it seems easier to keep the drill bit from walking around and I can keep it directly in the center. Works like a charm.

JHines · #3 08-08-2008, 04:12 PM

Did Van's see a photograph? In other words, are they advising you based on the same information as the tech counselor?

The rivets are either structurally sound or not. Everyone has a different opinion about how "good" rivets must be set to make them "completely happy", but if you ask 2 knowledgeable people straight up, YES or NO, "are these rivets structurally sound?" I would think you should get a consistent answer.

If they are sound, replacing them is only to satisfy your own personal aesthetic standards, with some incremental risk of causing damage in the replacement process.

danielhv · #4 08-08-2008, 04:48 PM

Quote:

Originally Posted by JHines

Did Van's see a photograph? In other words, are they advising you based on the same information as the tech counselor?

The rivets are either structurally sound or not. Everyone has a different opinion about how "good" rivets must be set to make them "completely happy", but if you ask 2 knowledgeable people straight up, YES or NO, "are these rivets structurally sound?" I would think you should get a consistent answer.

If they are sound, replacing them is only to satisfy your own personal aesthetic standards, with some incremental risk of causing damage in the replacement process.

True, however I have always felt that if I need to question somebody, then it needs to be replaced... especially if a Tech Counselor saw it in person and recommended replacement. I want no doubt in my mind that it is structurally sound... just piece of mind I suppose! Just my .02... YMMV

captainron · #5 08-08-2008, 05:52 PM

I think a rivet removal tool like this:
http://www.averytools.com/pc-528-21-...oval-tool.aspx
is a must-have item while building. OK, it's 60 bucks, but just sell it when you're done building. It centers itself on the domed head, and has a depth adjustment so you don't drill too deep. Practice with it, though.

Jeff R · #6 08-08-2008, 06:37 PM

A lot of builders think that "good enough" isn't. If it bugs you, then drill it out. If you bungle the attempt, well, that is the price of trying to achieve perfection.

Bugsy · #7 08-08-2008, 06:49 PM

I'm no engineer, but for 2 ugly rivets on my aileron bracket, I drilled them out twice and they ended up ugly. bought 5-6 rivets and drilled holes to size. Its now stronger and looks great. Didnt even ask if its nessesary I just dont want to worry about stuff like that when the bigger rivet cost a couple bucks.