A sabot looks like this:
This is a 4x2 with 1p (UK) slots and precut magnet holes. Ideal for an 8 figure group in Sharp Practice.
Here are the magnets, 5mm wide by 2mm deep, same as the holes in the MDF. They are small and powerful. I would be careful putting them near a credit card or any other electro-magnetic storage device.
This is a sabot with magnets installed.
As it happens the first one or two times I used these the magnets were slightly smaller than the holes so I secured them with a touch of superglue. This time I had to gently enlarge the holes with a small round file as the magnets wouldn't otherwise fit in. They did not need glued.
This is a completed sabot base (2x2 for Black Powder) with figures based on UK one pennies which are steel centred.
Matching up the terrain on the pennies with the terrain on the sabot marries the two together.
Tipping the sabot over does not dislodge the figures.
Nor does turning the sabot over.
The beauty of this technique is that you can have the same figures mounted on 2x2's for Black Powder and 4x2's for Sharp Practice. Just change the sabot. If you have a ruleset which requires 3x2's just make more sabots.
