A tale of two inserts

Two identical holes -
one is chamfered,
the other one not:

One hole works great,
the other one not:

And the one in the work piece:

Working with red oak can lead to some surprises, whether the poem works or not. As a result, I prefer to test; it prevents nasty surprises when working the metal inserts into a chunk of wood. Red oak tends to splinter a little; other woods do better than the photos show.

Had I not tested on a scrap of wood, I would have ruined the work piece. A 5-minute test saved the day for me – and it also kept my pulse near normal.

How do YOU prevent the kind of tear-out I show above, when using metal inserts?

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