TAP Plastics customer Rich built his own CNC router using 3D printed plans by V1 Engineering. He used polycarbonate on the sides to shield from stray material pieces, and PETG corner molding to support the drag train.
Shop polycarbonate here:
https://www.tapplastics.com/product/plastics/cut_to_size_plastic/polycarbonate_sheets/516
Shop corner molding here:
https://www.tapplastics.com/product/plastics/plastic_rods_tubes_shapes/corner_molding/152
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