Centuri Skylab Build, #KB-4, Part 5, Making Centering Rings

The outside circle is cut with scissors.

The traced pencil line will be a bit large.

Stack the rings on the smaller tube and reduce the diameter with 220 grit on a block.

Again, sand and check the fit.

Here's a good fit in the 2" lower tube.

I used my rotary punch to make an engine  hook notch in the nozzle bell centering ring.

The inside wall of the 3D printed nozzle was thicker than the original kit vacu-formed part. The ring sat high, almost over the top.

The diameter was cut down with scissors.

After rounding the edge - 

The final fit of the nozzle ring is recessed.