Back in the days of braces, catalogues listed
3 types of reamer;

The square-solid type, the hollow "half round" type,
and and solid semi-cylindrical type.

(The different types are for differing materials, but I don't recall
which is which).

But, apart from when enlarging holes in sheet materials,
these all make holes with substantial taper.

So - what were they used for? They're common,
both in catalogues, and "the wild" so people clearly
found uses for them.

Who needed strongly tapering holes of varying sizes?

  BugBear
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