Building
The Mast Insert
Mast
Plug & Insert
 |
You do
not need a machine shop to fabricate an insert from aluminum.
Here's how I built mine:
1. I traced the outline of my mast onto a piece of 3/4 inch plywood.
I then measured the wall thickness of my mast and, using a compass, transferred
this measurement onto the plywood inside the first tracing.
2. Using a scroll saw, I cut the plug just outside the second tracing.
This gave me a plug about 1/16" over size. I then drilled a 1 inch
hole in the middle of the outline so I could hold the plug while sliding
it in and out of the mast as I sanded for final shape.
3. Using a flat sanding wheel on my table saw, I sanded the plug
down to the final size of the mast interior, stopping often to verify the
fit to the inside of the mast.
4. When the wooden plug fit into the mast base snugly but without
binding, I traced the outline onto a piece of 3/4 inch thick, 6061 T-6
aluminum.
5. Using a metal cutting blade on my table saw, I rough cut the insert
out, again making sure that I remained outside the outline.
6. I used the side of the same metal cutting blade to do the final
grinding and shaping. It takes a little time this way but I made
do with the tools I had to work with.