Re: "Incident" repair advice
The fewer holes in the spar the better I'm sure. Newer Kitfoxes use a steel bracket that rivits to the spar, and slides inside the aluminum diagonal brace. That would be probably easier to use and drill to fit the existing holes. Then you only have to line up 4 holes instead of 8. With very carful measuring it can be done though. Might give Kitfox a call and see what they suggest. Jim Chuk
Re: "Incident" repair advice
Just happened to look at your first pictures and see that your spars have the internal extruded verticle stiffener. I would personally be less worried about some extra holes in these spars than ones without that type of stiffener. I would think they are stronger than the .065" spars used now on Kitfoxes. Just my opinion though. Another question to throw by John at Kitfox if you call him. Jim Chuk
Re: "Incident" repair advice
I was thinking that Jim's idea was great and I would think drilling the holes to accommodate the next size up rivet would take care of a sloppy install of the same size. To place the holes in the brackets you can use a Hole Duplicator-Bushing Type available from Aircraft Spruce.
Eddie
1 Attachment(s)
Re: "Incident" repair advice
Photo of drag tube bracket on Model 3, S/n 1013 which was built in 1991.
Hope this helps.Felt there was a Service Letter, or similar update information put out on forum, but am unable to locate it. Ian
Re: "Incident" repair advice
Looking at the brackets, it looks like it would be hard to hit the old holes using them. The old holes would probably be under the welded tube somewhat. There are 6 holes in them however, so maybe intentionally not hitting the old holes and still using the original style aluminum tubes isn't so much of a concern. Jim Chuk
4 Attachment(s)
Re: "Incident" repair advice
Hi Robert,
I would not bother with installing the new drag tube brackets, probably just replicate a new diagonal brace per the manual and attach with Hysol and next upsize rivet. First end is easy to fit to the existing mounting hole in the spar, make a simple D.I.Y. hole duplicator for the other (attached pics of one I used for locating spar bushing holes). You can temporarily rivet the hole replicator into the existing hole with the original rivet size called for in the manual, locate the hole position on the drag tube end tab, then drill out the temp rivet. Drill out spar hole for next upsize rivet and final mounting. Also, I recommend adding corner gussets between the diagonal bracing and spar. Coat ply gusset with Hysol to prevent water infiltration.
Re: "Incident" repair advice
while your there you could add rib stitching. No weight, no time like the present.
Re: "Incident" repair advice
Quote:
Originally Posted by
avidflyer
Good that you found the damage. Better safe than sorry. Just out of curiosity, I wonder what difference you would find if you measure diagonally on the spars before and after you remove the bent parts. With the S curve in the one diagonal brace, the wing is racked. It should go right back to where it's supposed to be when the braces are removed. It would be nice to know how much difference in measurement you find as a way of checking other wings in the future. If the wing is sitting up side down, you could push a bolt or pin up through the holes in the fuselage end of the wing to hook a tape on. Make a mark on the ends of each spar center to measure to. I never thought about this when I first answered your question about your wing damage. It probably would have told you there was damage inside the wing even before you uncovered it. JImChuk
Jim, checked rack in the wing it's 5/16 ".
Robert
Re: "Incident" repair advice
Thanks for the follow up info Robert. If the wing was built square to begin with, that would be a way to determine if there was damage on a wing then. Are all wings built square to begin with? Maybe not. Probably most are pretty close though. When you remove the braces, please measure the wing to see if it goes back to square. Take care, Jim Chuk
Re: "Incident" repair advice
Ya ..the square... Start to mesure from spar end on fuselage side,and from there Mark two line to the end (wingtips side) im not sure , i think it is 156''.and after you can take mesurement for the square