Designed this multi-part mould to cast weights out of concrete. While weight accuracy is only around +/- 15% depending on your concrete and aggregates, the consistency between weights is about 2%.
I chose to fit 28mm bars to maximise compatibility, if you use 50mm olympic bars you'll need to adjust this (see attached source file).
Source file (FreeCAD) for the 2.5kg mould is included for customization. I used the FCInfo macro to determine weight for a given concrete density (I used a concrete density of about 2.2kg/l). Use the Spreadsheet to modify diameters and thicknesses, the parts should update automatically.
I've included a post-print video (https://youtu.be/T-6MKUg9bLs) to show the casting process itself to illustrate mould assembly, tips to get a successful cast and mould disassembly:
| 10kg_Bottom.stl | 161.8KB | |
| 10kg_Jig.stl | 6.1KB | |
| 10kg_Ring_28mm.stl | 271.3KB | |
| 10kg_Top.stl | 545.7KB | |
| 2.5kg_Bottom.stl | 209.8KB | |
| 2.5kg_Jig.stl | 6.7KB | |
| 2.5kg_Ring_28mm.stl | 271.3KB | |
| 2.5kg_Top.stl | 593.8KB | |
| 20kg_Bottom.stl | 208.0KB | |
| 20kg_Jig.stl | 5.9KB | |
| 20kg_Ring_28mm.stl | 271.3KB | |
| 20kg_Top.stl | 592.1KB | |
| 5kg_Bottom.stl | 208.7KB | |
| 5kg_Jig_28mm.stl | 6.3KB | |
| 5kg_Ring_28mm.stl | 271.3KB | |
| 5kg_Top.stl | 592.6KB | |
| Spud28.stl | 386.7KB | |
| Weights_Mould_2.5kg.FCStd | 633.3KB |
