On 22/05/2021 22:29, Steve Walker wrote:
On 22/05/2021 16:32, David wrote:
I have a gap into which I want to insert a cut piece of wood.
[More detail available if necessary.]

The gap is around 345 mm but there is a slight recess so I can't
eyeball a
tape with the exact measurement (although I haven't found that very
accurate when I'm doing it anyway).

I thought of a sliding measure which could be locked when it fitted the
internal dimensions.

I looked on line but they all seem to be 1 metre plus minimum length.

Does anyone know of such a measure or have a sneaky alternative method?

I was hoping to set a rigid measure, then transfer the measurement
directly to a piece of wood which I would then cut to fit exactly.

for 345mm, I'd suggest two overlapping 12" steel rules.
+1, or just two pieces of wood. It would be daft to buy a special widget
when it's so quick and easy to make something suitable.