I've made several of this kit and never had this problem. The ID of the upper tube is smaller than others I've done. Pictured is a walnut blank that the bushing doesn't fit into. Thinking I may have some substance inside I tried a new brass from the kit pictured and it too is too small for the bushing. Am I missing something obvious or did I get a couple of bad kits? Thanks for your help.
I've only made rollerballs and fountain pens. Crazy situation, maybe I switched the bushings with another kit but it was the only one I was working on. The smaller two are fine.