| Digest Nr | Subject and Author |
 |
| 2006.01.22.08 | Valve Facings of Packing Leather, from Joel Cluskey |
| 2001.06.30.08 | Gluing Leather Valve Facings, from Paul Manganaro |
| 2001.06.30.07 | Gluing Leather Valve Facings, from Don Teach |
| 2001.06.29.03 | Patent Leather Valve Facings, from Rob Buckingham |
| 2001.04.18.03 | Valve Facings From PPCo, from Roger Waring |
| 2001.04.17.04 | Vacuum Valve Facings From PPCo, from John Rutoskey |
| 2001.04.15.06 | Patent Leather Valve Facings from PPCo, from Al Pebworth |
| 2001.04.14.03 | Vacuum Valve Facings from PPCo, from Roger Waring |
| 2000.04.01.14 | Orchestrelle Valve Facings, from Martin Anderson |
| 1999.03.25.10 | Aeolian Valve Facings from PPCo., from Stephen Kent Goodman |
| 1997.12.12.09 | Neoprene Valve Facings Collect Dust, from Richard Vance |
| 1997.12.11.09 | Neoprene Valve Facings Collect Dust, from John A. Tuttle |
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