thingiverse
A rowlock copied from one that I bought. Inside diameter is 54mm. I have my doubts about whether or not this would work if actually printed. I'd at least advise that it be printed at 100% infill. If you do print it, lay it flat on the plate to ensure that the layer lines are in the best orientation for strength.
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This STL file is compatible with most FDM 3D printers (Creality Ender 3, Prusa MK3S+, Bambu Lab, etc.) and resin printers (Elegoo, Anycubic). Check the original page for recommended print settings and materials.
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