Nii, the rakes are kinda like the equivalent of what stone sculptors use. After roughing out the form with a sharp, pointed chisel, the artist refines the shapes with various sizes of rakes - these are toothed chisels which break up the crystalline surface of the stone without taking off great lumps (marble particularly is very brittle and must be treated with care)
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This leaves the pattern you will see on many of Michelangelos sculptures, particularly the slaves. The last carving stage is where the patterns left by the rake are removed with flat chisels, leaving quite a flate surface, before files, rasps, etc are used for the final finish.
In Z, the rake will help flesh out the forms very quickly before the smooth tool and others take the place of the flat chisel. It’ll be a great help to have the rake tools, especially for trad. sculptors!
hope this helps! 