ER32 Adapter(purchased)

[Rickabilly]

You are right, the threads mean next to nothing, it's all about the spigot and register face, from what I have read above, the odds are that the bore that locates on the spindle spigot was oversized by four or five thou, of course the shop'll never admit that, at least not in writing, on the bright side, the morse taper version is probably much more adaptable and so more useful for a "Junior Swarf making student" you can use it on a mill, drill press, headstock, tailstock, on anything that takes morse taper which is pretty much any machine tool...

Thanks for the update

Regards
Rick