Nice, I use ER20 collets in my CNC router but I yet to make a holder for the collets.here is another one for the group. @David might get some use
collet block for er20 collets, like used in the 2.2kw spindles, attached is the block with 15 spaces and a single block with only 1 space
I print it upside down, and select no top layer, saves print time & filament
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