Never seen the article so I can't help there.
Precision shunts are rather expensive and are made from alloys with low temperature coefficient and also the alloy needs a low thermal emf relative to the copper millivolt connections. For a rough indication for wind power you can get away with many crude dodges. Copper has a high coefficient of resistance with temperature but even so is good enough to give a reasonable indication for wind power. In many cases you can take the mV drop on a feed cable over a chosen distance to give the meter fsd mV ( usually 75 for analogue or 50/100 for digital). You can use a piece of solid copper wire as the shunt and wire it into the circuit like a shunt.
If you want something more compact with higher drop in a shorter length you can use steel and I can well imagine a small diameter allthread being used and you can use pairs of nuts to attach the main connections ( ends) and the sensing points ( between the ends). I don't like the idea as the resistance of the mV sensing points will eventually change with thermal cycling and rust and corrosion will take place unless you have a dry environment.
I think for a cheap reliable shunt where high accuracy is not needed the best option is a strip of stainless steel. If you weld or braze the mV sensing points then it will stay in calibration for ever. If you can't do that then you will need to bolt the sensing wires on and as long as you use a longer and thicker strip to limit surface temperature and use stainless bolts it should still be good for a long time. With a bit of thought you may be able to bend it into a shape that will let you use the distance between the meter terminals as the sensing points ( analogue only).
Never attach the power cables to the meter sensing points, the power connections must be outside the sensing points.
Unless you have another meter to calibrate it you will need to do calculations from the resistivity of the material ( somewhere here is the length of a certain size copper wire for a given mv drop but I couldn't find it).
If you have a multimeter you should be able to calibrate at 10A and that would be fine for something up to 50A. Just use a battery to supply current to the multimeter and shunt in series and a load to set the 10A. Car headlamps or a length of steel fencing wire would do to set current if you don't have anything better. If for solar or if you have a solar set up the solar panels would give a controlled current for calibrating.
Flux
