I did a little more on the ADAHRS bracket this morning, but the majority of my day was spent working on the the side steps. These are a bugger to fit.
I started on the right hand side by first drilling a large hole through the external skin. I then enlarged the hole with a cutting bit so the tube portion of the step kit fit easily through. Then I needed to scollop out the two floor angle brackets....another job for the cutter, this time on an extension bit. Lastly (for this portion of the job) I manufactured extension pieces for a couple of my hole reamers and cut out the hole in the floor rib. This also then needed to be enlarged.
When I fitted the step I saw that the tube was about 4mm (3/16") too long. This came as no suprise as I'd read a couple other builders logs where this was the case. I simply cut off the end of the tube with my hacksaw and smoothed off with a file. When I then reinstalled the step it fit quite neatly up to the fuselage skin. I just "tickled up" both holes a bit with the cutting bit and the mounting flange then pulled up very well. Of course the bottom left corner will need bending to match the shape of the fuselage skin, but I'll get into that tomorrow.
I finished today off by drilling all the holes in the step flange and then match drilling to the fuselage. For the vertical row of rivets that align with the bulkhead flange, I opted for just four rivets instead of five as shown on the drawings. This allows a more logical placement of new rivets in between the existing bulkhead rivets.
Oh yeah, I also drilled and bolted the polyurethane mounting block to the floor rib (shown clamped in place in the first photo below).
Drilling the hole through the floor ribs was a bugger of a job
