| Year | 1921 |
| Date | 21-Apr |
| Volume | 44 |
| Issue | 1,043 |
| Page | 310 |
| Category | Workshop Topics |
| Part | |
| Title | Correcting the Pitch of a Worm |
| Author | |
| Notes | Drummond 3 1/2" lathe set up for screw-cutting a worm & correcting the pitch simultaneously, extension piece to top slide screw & detail of inclined plane |