| Year | 2017 |
| Date | 03-Mar |
| Volume | 218 |
| Issue | 4,555 |
| Page | 369 |
| Category | Workshop |
| Part | |
| Title | Making a Miniature Changeover Valve |
| Author | Dennis Stones |
| Notes | Deploys his experience in plastics engineering to make a potentially useful component part. Background, valve design parameters, material selection (valve body), material selection (valve spool), reference |