when centrifuge loading, one is balancing two objects to each other…so one can go lower tech.
it may not be cheaper, but it really helps get the concept of “balanced” across, and that can be important in some environments.
when folks are spinning canning jars an/or their equivalents, with a frit of some sort in the middle, they also need to consider the relative loadings of solids to liquids between baskets. where in the bucket the load is, changes the forces involved. so loads should be “balanced” here as well.
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Edit: there is the caveat that you need to first confirm that at max fill, you’re not exceeding max loading for the fuge. From there out you don’t really care how much is in each bucket, just that they are the same.