I needed bushing to make this flat top pen and did not have the correct size.
Tried some brass ferrules but they did not fit snug enough on the adapters.
What I found out is that the steel used for the spacers that came with my mandrel saver are of mild enough steel that I was able to turn them down to fit in the adapters for my centers. I used a HSS parting tool. Yes, I did have to sharpen it afterward but not a lot. I got the same close fit as with the 7mm tubes. All of the parts-to-wood transitions on this pen are excellent. A spacer like the ones used is in the center. They do look more like some kind of cast metal. Definitely not machined like the bushing sets or the adapters for turning on centers.
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