2.5 Hours -
I decided to take a break from rib deburring and fluting. The leading edge and tank ribs will have to wait a few more days. Instead, I worked on drilling the holes that will be used for Van’s conduit in the wings. At a minimum, this conduit will be used for running wires to the wing tips for landing, taxi, position and strobe lights. I may use it to run wires to an autopilot servo in the right wing as well.
Van’s instructions for the location of the conduit holes simply state to make the hole in the lower 1/3 of the rib somewhere between the two largest lightening holes. Positioning the holes can be made as complicated as you want, but all you really need to do is pick a spot and then make a template from paper or cardboard that will let you duplicate the spot on the remaining ribs. I made my template from a piece of thick cardboard that was used as packing in the crate the skins came in. Once I picked the spot for my conduit, I measured where the marking was in relation to various parts of the rib and transferred those measurements to the cardboard. I punched a small hole in the cardboard that would allow me to mark the location of the hole with a sharpie.
A simple cardboard template was all I needed to locate and drill the conduit holes.
I marked the location for the conduit hole on each rib using the template. Then, I center punched the location to help start the drill.
Once all of the ribs were marked, I used a center punch to create a nice starting point for my drill. The holes were then drilled to #30.
I drilled each hole to #30 first.
The #30 holes were then enlarged to 3/4” using a step-drill on my drill press. I placed a piece of plywood under the rib and drilled the rib/plywood together in order to prevent the drill from chattering and making an oval-shaped hole.
The #30 holes was used to start the step drill.
Drilling into a piece of wood kept the step drill from wobbling. The holes were drilled to 0.75" per Van's instructions.
Another shot for the FAA. Yep...I drilled those holes.
Conduit holes in two ribs...I was really worried they wouldn't line up!
Once all of the holes were drilled to 3/4”, I deburred the holes and then started to hang the ribs on the left spar. There’s no real need to do this at this point, but I wanted to make sure the conduit holes lined up. OK, I really just wanted to see something in my garage that vaguely resembled a wing!
With the ribs clecoed to the left spar, it is finally starting to look like a wing.
The obligatory shot down the lightening holes
My attempt to show that the conduit holes are nicely aligned.
