It is very easy and cheap to build olympic barbell sized micro loading.
- keyhole saw
- hole saw for 50mm hole, for a power drill
- tape measure
- Best is wood, preferably a large square board
Measure the dimensions of the board and calculate the surface, then
measure the weight.
Lets say it's 300mm x 310mm = 910cm², and 1100 gr:
Calculate the specific weight per cm²,
910cm² / 1100 gr = 0.873gr per cm²
Calculate the surface of a 5cm diameter disc of the material,
2.5cm x 2.5cm x PI = 19,63cm²
Calculate the weight of such a disc
19.63 * 0.873 ~ 17gr
Add that to the weight of the disc you plan to build, lets say 250gr
250gr + 17gr = 267gr
Calculate the diameter of a disc of that weight from the given material,
Radius = SQRT (267gr * 0.873 / PI)
Radius = 8.61cm
Use the compass to mark a circle with the radius 8.61cm and an inner circle with radius 2.5cm, use the keyhole saw to saw the outer circle out, use the hole saw to remove the inner circle and voila, a 250gr micro loading plate for your olympic barbell... If you use powered tools the time to build two is ~5--10min and
the cost is next to nothing. BTW I don't own all the tools I use, but I know people who have them and will lend them to me or a more than happy to help out.