AVI Nike Tomahawk Build Part 4 Engine Mount Centering Rings

The Nike  fin can has two plastic centering rings that fit a 18mm engine mount tube. On this model I wanted to convert it to a 24mm mount.

Because the plastic rings fit so well into the fin unit I decided to use them in the model. They will need to be opened up for the larger diameter engines.

The top of the rings was hit with some 220 grit sandpaper on a block. This roughened the surface to better accept a fine point Sharpie pen line.

I had some scrap 24mm heavy wall tubing.
The tube was centered over both rings and traced.

Here's both rings with the traced 24mm lines.

The lower ring is on the left, the upper ring on the right.

Because the tracing was a little outside the 24mm tube diameter, make your cuts a little inside the line.
This cut wasn't easy and took a few passes to get through the plastic.
We'll sand the cut circle to the correct diameter in the next post.