Comment

Comment by Lawrence Van Egmond on May 22, 2012 at 12:50am

It is a common problem and it helps if you use a high speed drill and once through top skin use very light pressure so the rib is not pushed down and let the bit do the work. Cleco  as you go and it will help hold everything in place.

Comment by David A. Judkins on May 17, 2012 at 9:56pm

Good comments! I like the idea about the rib molds.

Comment by Phil Smith on May 15, 2012 at 9:53am

OK Kids,

 

You have a problem much like I experienced - I think. That is the ribs flexing while you drill causing an "oblong" or miss-formed hole.  Simple fix is to FAB some inserts that closely mirror the "interior of the rib" from wood - plywood or OSB works well - that fit inside the ribs for support during drilling. Also might think ahead and plan to do this on most of the rest of the "rib" structures in the wings, flaperons and slats etc. You just put the rib on the wood and trace around the outside then cut a little smaller. You don't have to have it exact just snug where you want the supprort. Once you get one then you copy the rest.  Not the most fun but works well.  I found that I had to be very carefull in these areas.

Also sharp drill bits are a neccesity.  If you haven't dicovered "The Drill Doctor" sharpening machine yet - look it up it saves a lot of grief as you drill along. I don't remember the model I have - but is the mid range model with the ability to put a "split point" on the drill bits. Read the instructions and get the set-up right and you'll love it - probably end up sharpening all your drill bits.  Another tip, when I sharpen bits I finish off the drill bit by marking the "cutting edge" with red marker so I know where I am - the marker wears off immediately when you drill but you know what bits are freshley sharpened and the ones you have used..

Still Grinnin !!!!

Phil

Comment by David A. Judkins on May 13, 2012 at 11:04pm

Yes, I think I understand. I'll try that next weekend when I resume work. Thanks again!

Comment by David A. Judkins on May 13, 2012 at 9:28pm

Thanks, guys, for the comments. Should the angle cover the area around the damage only or should it extended out to help distribute the load?

Comment by Geoff Klestadt on May 13, 2012 at 3:16pm

Don't worry, did the same. Easily fixed with some L angle. Give Caleb a call.