In making pots theres usually very little wastage and once a piece has been turned, taking off the excess clay, there tends to be a lot of shavings. These shavings collect in the wheel tray and are put into the reclaim bucket where they’re mixed with water to create a slurry.
Doing this reconstitutes clay when it’s become too dried out to throw again, ideally your looking to create a smooth texture with no lumps which can cause problems when your throwing. Once it’s broken down in the bucket it’s then churned up into a slip or liquid clay which has a high percentage of water, it can’t be thrown so some of the water needs to come out.
Putting the slip on plaster blocks draws the water out of the clay to get it back to a smooth throwing consistency. The amount of time it spends on the block varies depending on how much water there is in the clay, how saturated the block is with water and how dry the ambient temperature is.
Once it’s spent a few days on the slab it’s usually ready to wedge up and be thrown again! Generally the reclaim clay tends to have a higher percentage of water which means pots made using this clay do tend to shrink up to half a centimeter more when they’re fired.