Nose Bowl

Well , winter returned for Sunday and Monday so no progress on the Cub. I can heat the air in the shop no problem , but my hands are just too old to work with cold tools. Today was beautiful and warmed up into the high 50's. After lunch I went to work on the cowl and finished at 7:30.  I worked on fitting the nose bowl to the lower cowl. I installed everything on the airplane and made the final adjustments before drilling the rivet holes. The nose bowl had multiple holes where it had been installed and removed before. Some lined up and some did not. You can see in this picture it was an ugly situation.

  I've been thinking about this for a couple days and the solution came to me as I was working today. The rivets would have to be installed with washers to add bearing area. This would have been easy with pop rivets, however I would never use those for this application, too much vibration. I ended up using a short length of vinyl tubing to push the washer into place as the rivet was squeezed or driven . The tubing is cut just a little shorter than the rivet before it is driven, like this.

  You then drive the rivet normally and the tubing compresses and pushes the washer down tight. The rivet expands the tubing and the shop head forms normally. Pull the tubing off and it's good to go.

Here are a few shots of the completed job. One of the problems was that the nose bowl did not exactly match the lower cowl. Since they both have wire beads at the edge I could not just trim them to match.
You can see it in these pictures at the joint

I ended up using a small triangular filler piece to continue the cowl line and make this less obvious. I think it will look OK with some paint on it.

Tomorrow I will add the doublers at the carb air intake and the heater air inlet and the cowl will be pretty much finished. Still no word on the exhaust, been 3 weeks today. BC wanted to say HI to his mom!