| Year | 1914 |
| Date | 17-Dec |
| Volume | 31 |
| Issue | 712 |
| Page | 546 |
| Category | Workshop Difficulties |
| Part | |
| Title | Commutator Making and Gun Rifling |
| Author | B.W.Simpson |
| Notes | Awarded a prize in our Workshop Difficulties Competition. Rig up for cutting commutator casting into segments, cutting a spiral slot in guide rod |