1.5 Hours -
My Dad came over this afternoon, and we got started on the spars. However, we didn’t make it very far. The first step is to attach a bunch of platenuts to the spars. To do this, the holes in the spars have to be drilled to size, then they have to be countersunk. Well, my #40 countersink lasted about 10 holes before the guide broke off. The rest of the #40 rivet holes will have to wait until I get a new countersink bit.
My Dad started drilling the spar while I set up the countersink.
After my Dad left, I went back into the garage and attached the first few platenuts (all of the ones that had been countersunk). For the screw hole, I’m going to use the Van’s method…rivet the platenut on and then use #30 countersink on the screw hole. Rather than making a guide from scrape aluminum, the platenut acts as the guide for the countersink bit. I set my countersink up for a .370″ diameter countersink and went to work. This method seemed to work well for the first few holes, so I think I’ll stick with it.
The first few tank attach platenuts are installed...the rest will have to wait until I get a new #40 countersink bit.
Van's recommends a countersink diameter of .365"-.375" for a #8 screw. I set up my countersink for the middle.
Hopefully, I can have a new #40 countersink delivered within a couple of days. No real rush though as I can only work on the plane in the evenings during the week, and the heat at that time of day greatly limits the amount of time I want to spend in the garage.
