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paulfer

I'm New Here
Hi Guys

I'm a newbie here. I have just started on my 8 and have never used these 12 inch drill bits before. So, in my infinite wisdom, I have cocked up! I think.

The plans called for me to use the long drill bit to drill thru HS810-1 and the HS404/405/FWD HS702 spar. Well, on my first hole, i drilled a bit skew. Not knowing exactly how to hold the condounded drill bit! So now, that rivet, which i havent riveted yet, sits a bit skew.

Do i just go ahead an rivet that rivet in skew, or order a whole new HS 810-1 reinforcing angle??

If i do rivet this rivet as is. Any advice as how to hit it. Do i hit the thing in line with the rivet shaft or parallel to the spar/reinformcing plate?

Regds
 
Skewed Rivet Hole

In general, the rivet must be driven perpendicular to both the structure and the rivet shaft. If the hole isn't straight the rivet head will not sit properly on the surface...when you hit it with the rivet gun the rivet head will probably crack since one edge of the rivet head/shaft will make solid contact with the structure and the other edge won't.

I had a similar problem (same parts, same holes) except that I was using an angle drill attachment for the first time...lesson learned: don't try out a new tool on the RV parts! I now have a small pile of scrap aluminum for practice.

I decided to order new parts, but a search here on VAF will show a number of opinions (such as drilling an oversize hole and using an AN series bolt instead of a rivet). This might work if you have sufficient edge clearance on the parts for a larger hole...in my case I did not.

If in doubt, call Van's.

Good luck,
Mike
 
paulfer said:
Do i just go ahead an rivet that rivet in skew, or order a whole new HS 810-1 reinforcing angle??.....If i do rivet this rivet as is.......
Click to expand...
Paul,

The short answer is no, you should never shoot a rivet into an obviously crooked hole. The manufactured head of that rivet is sure to be greatly weakened. I'd wager the B744 you fly does not sport such rivets so why should your RV?

There are so many variables in play that it is difficult to give a definitive answer to your specific question without seeing the assembly. One thing is for sure though. Crooked holes are never approved in certified aircraft UNLESS there is sufficient material thickness to counterbore the hole or machine "spot face" the hole at that nonstandard angle. Doing so would allow the manufactured head of the fastener to correctly sit perfectly flush or perpendicular to the surface of the material. Although widely available, reverse spot facers and counterbores are special tools the homebuilder is not likely to possess.

Short of that, the hole can be straightened which you CAN do yourself without spending any money but does require a bit of planning and perhaps a good drill press. But again, I don't know what size the hole is now and if there is enough e.d to allow you bring the hole up to 5/32" or even 3/16" if required. If it is possible to straighten the hole, contact Van's and ask an engineer if an oversize hole is acceptable in that location. Without getting too wordy, here is a link to a common sheet metal technique I posted some time ago that is often used in production shops to move or straighten a hole. The second paragraph explains how you can make a custom bushing block for a specific repair situation.

http://www.vansairforce.com/community/showthread.php?t=11769
 
Welcome to the club

By the way, dont get discouraged. I personally have a "wall of shame" where my practice parts are hanging.I expect Vans sells a whole airframe for every 10 they sell just in replacement parts for us to "learn" on.
 
Yep

Harland E. [n.m. u.s.a.] said:
By the way, dont get discouraged. I personally have a "wall of shame" where my practice parts are hanging.I expect Vans sells a whole airframe for every 10 they sell just in replacement parts for us to "learn" on.
Click to expand...

Me too! Some who has built one of these things and doesn't have a few 'sentimental pieces' laying around is either a pro, in denial or just a liar.
 
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