geraldthehamster wrote:
I need to drill accurately some holes for taps in a 40mm thick beech
worktop.

How might I ensure that I am drilling exactly vertically, with my hand-
held drill?


Get a piece of wood with parallel sides. Drill an accurately "vertical"
hole in it using, say, a pillar drill. Place the piece of wood over
worktop and use it as a guide for the new hole.

In fact, you could use anything with an accurately positioned hole - it
does not have to be the same diamater as the taps need - you can drill a
modest hole and enlarge it fairly accurately. So start searching - there
are all sorts of bits and pieces on vehcles that might do. If the item
already has a hole it doesn't even need to have two parallel surfaces.

--
Rod

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