More Firewall (2h)

After yesterday’s success, it was back to the firewall. But first I pilot drilled the cabin frame through the pre-drilled holes in the cabin sides.

I need to do the same at the top but until I get a step ladder in the hangar it is too high for me to get to. So back to the firewall.

The forward gusset needs two rivet lines, 10mm from each edge, seven holes 30mm apart.

I pilot drilled them on the bench and then re-clamped the metal to the upper angle and top stiffener prior to drilling.

The upper angle overlaps the nose gear leg hole and so it has to be trimmed.

I decided to do this with the snips and this was a good example where not using the right tool makes a task impossibly long. It took me forever to get a good enough piece cut out, but I bet with an grinding wheel it could have been done in no time. Ah well.

There is a nylon bearing that goes inside the top stiffener to prevent the nose gear leg from rubbing against the metal. The instructions say that the top edge of the bearing needs to be angled to match the curve of the flange of the stiffener. I had a stab at this with a file and as you can see I didn’t do a great job of it. But when I put the bearing in the right place it doesn’t touch the curve so I don’t really see that it matters. Before final installation I may have another go.

To get the position of the bearing just right, I put the nose gear leg through the bearing and moved it up and down until it was only supported by the bearing, and then I pilot drilled the first two holes.

Looks like I could not have gotten it any better – a first!

With the bearing pilot drilled in all four places I attached it to the top stiffener and upper angle and opened all the holes to 3/6″; each hole will get an AN3A-6 bolt.

And then it was lunchtime, and I did not return.