M.POWER 3D Combination Square — and the Amazon Alternative

M.Power is a British toolmaker whose products reach the US market unevenly — some items are on Amazon, others only through specialist retailers. The square is one of the less reliably stocked ones.

What matters more is the case for owning a small precision square at all, because most shops have a 12 in combination square and stop there.

Small gets used

A 12 in combination square is the right tool for laying out across a panel. It is also heavy, long and awkward for the dozen small checks that happen constantly: is this shoulder square, is this tenon face flat, how deep is that rebate.

A 4 in double square fits in a pocket and gets reached for instead of eyeballed. Tools that are convenient get used, and a check you actually make beats a more accurate one you skip.

Check it is square

This applies to any square at any price, and almost nobody does it.

Put the stock against the jointed edge of a wide board and mark a line down the blade. Flip the square over, register on the same edge at the same point, and mark again. If the square is true, the two lines are on top of each other. If it is out, they diverge — and the divergence is double the error, which makes it easy to see.

Do this when the square arrives. A square that is out of square is worse than no square, because it puts the same error into everything.

The blade as a gauge

The sliding blade is not just for squaring. Lock it 20 mm out and it becomes a depth gauge for a rebate, a height setter for a saw blade, or a marking gauge you can run along an edge with a pencil at the blade tip.

That second life is why a double or combination square earns its place over a fixed try square.