Having had another cup of tea and a sit down, I decided that since the screws had arrived I would continue the work on the nav lights.
The new brass thumb screws are metric, M5 to be exact, whereas the older ones, probably over 50 years old, are imperial. No idea what they are but they are smaller than M5 and the new thumb screws are too large to fit in the original holes. This means that I need to tap the existing holes to take an M5 thread. I gathered the parts together and set to.
The imperial hole was wide enough to use the M5 tap directly and did not need to be drilled out. The new thread didn’t take long to make, the initial thread or two always being the hardest to get right.
The new thumb screw was inserted to make sure that it fit, and, as you can see, it did.
Next the new countersunk machine screws were used to attach the base plate back to the cabin side. I used normal nuts to do this as the work is not completed as yet. I’ll need to take the plate off and on again a few times before the final fitting and at that time I shall use self-locking nuts. Still, for now, this is looking good.
Finally, the outer housing was screwed in place. Looks pretty good. With this successfully completed I carried out the same process on the other side.
The brass thumb screws will need to have a slot made in the head to allow it to be tightened with a screwdriver as the head is a very tight fit into the recess in the housing, but this was expected. I’ll use two of the spares to make the slots, either using the CNC router or a hacksaw.
All in all, a very productive day and although the tasks I have done today are quite small ones, I feel as though I am making progress.
Time for a cup of tea.