Building An Airplane From Plans
After finishing the horizontal stabilizer we decided to install the custom “splice strip” for the fiberglass tip. The sheetmetal strip slipped easily between the top rib and the skin. The dimples aligned it right in place. Here are the rivets inserted:
Dan finished riveting the frame together. He put the skins on with clecos:
Here is a close up of the leading edge, looks really nice. I am glad our tech councilor suggested to get a good bend on the leading edge.
Here is the leading edge looking from the outboard side:
Here is the training edge with the hinge:
Just before staring to rivet
One skin side flush riveted:
Here is the completed Horizintal Stabilizer:
Dan noted that you have to really have the rivet gun square/flat with the skin or the rivet might become tipped a little in the dimple. Only a couple had to be drilled out.
After admiring our work and gloating for a minute we hung it on the wall.
We assembled the complete horizontal stabilizer frame and skins one last time to make sure all the parts were in the right place.
We started with the (rear) main spar assembly (SNX-T3-01). The inner rivets are fine, but the outer ones are closer to the flange so you cannot get the rivet gun in there without deflecting the flange
Dan had previously made some spacers to put between the rivet head and the rivet gun. We decided to make a new spacer with a smaller bore to fit the rivet stem better. We had some 3/8 rod and we cut off a piece and drilled a hole. The first two attempts had the hole off center and it looked really bad. The next one was too tall and the gun could not grip the stem. The fourth one finally worked.
It’s amazing how much time these little side exercises take up. We finished riveting the main spar.
We started on the front spar (SNZ-T03-05).
However we decided t rivet SNX-T04-01 (the inner ribs) to SNX-T03-05, forward root clip. The plans show to rivet this later with assembling the whole frame, but it looks more cramped and awkward to get a rivet puller in there.
On the front spar we were careful of the orientation of the inner most rivets, the first rows (on each side) are flipped from the rest.
I bought a 60 gallon Craftsman air compressor off of craigslist last fall. It has great specs, 11.5 cfm at 90 psi. It is a 220v model.
When we went to check it out we ran it and it was loud lout loud. A real clack clack clak… You can’t talk to someone next to you. I thought this was the normal sound for large compressor and I bought it and we brought it back to the workshop. A friend who is building a Harmon Rocket has a new compressor and Dan mentioned it is really quiet compared to the beast I bought. Well I finally tore is apart and after consulting with Dan and some engine guys at work, the crankshaft bearings are scored and beat up. So I ordered a new set and we will see if that solves the problem. In the meantime I am cleaning it up from all the paint residue inside and out from the previous owner.
Interesting side note on the bearings. I could move the connecting rod back and forth on the crankshaft and wrist pin and clack against the shoulders on the crankshaft. The bearings are narrower than the width of the connecting rod and cap. But there does not seem to be any wear on the sides of the connecting rod and end cap, I assume the crankshaft would be harder than the others. I guess you would call this side play on the connecting rod.