A NEW HEATING SOLUTION
I am getting ready to match drill and set all of the wingtip attachment nutplates, but there is one item of business that must come first. Heat. My hangar is not insulated, or at least any more than corrugated steel barns naturally are. Therefore, my tiny little propane heater that you could only feel when right next to it had to be replaced. And if you are going to replace a 10,000 BTU tabletop heater, you bet it is with a 220,000 BTU monstrosity that could heat the whole outdoors.
There she is. My wife “got this for me” as an “early Valentine’s Day present”, which is shorthand for I bought a new heater.
The ambient temperature in the hangar today was hovering just above freezing. I turned on the heater and took care of that. Once this thing starts barking fire, hold on tight. Okay, enough of this. On to the attachment nutplates!
CUTTING THE WINGTIPS TO SIZE
First, you have shape the wingtips as they do not intrinsically come ready to screw in to place. Additionally, I am using the ZipTips product from Aveo Engineering, so I have a few additional considerations while cutting to size. I trimmed the inboard edge of the ZipTips all the way around down to about 1/2 inch. This is the measured clearance I obtained from the wing.
Next, I cut away additional material in order to allow for aileron clearance. Van’s recommends a 3/16 inch clearance between the outboard edge of the aileron and in the inboard edge of the wingtip. As you can see below, I think handled this one pretty well.
MATCH DRILLING
Now it is time to mount the wingtips and match drill to the wing skins. Because the wingtips are not uniformly gapped, several mountings took place with some sanding in between. Overall, I much preferred taking too little on the initial cut as this sanded down nicely. In order to get the wings to stay put, I used some tape to hold them securely in place while I started the match drilling. You have to really push down to make sure that you seat the wingtip into the leading edge of the wing in order to avoid buckling down the line. Overall, I was pleased with how this process went.
FINALLY, THE ATTACHMENT NUTPLATES
Once the match drilling is complete, it is time to open up the holes for #6 screws and line up some nutplates. I found it fairly easy to cleco the nutplate in place and drill the #40 rivet holes. In order to get them lined up perfectly, you may consider clecoing even more as you go along, but I did not find it to be a requirement. Similar to the access panels, I countersunk the screw holes as well as the rivet holes in the same fashion. Finally, it came time to rivet them in place. Because there are so many attachment nutplates along the wingtip edge, I found it best to rivet the nutplates on with the screw in place. This allowed for any deformation to occur while the screw was in place. Once again, I am pleased with how this all turned out. One down, one to go!
