From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Comparison table of tests on various varnished fabric boards and Bakelite materials.
| Identifier | ExFiles\Box 39\3\ Scan252 | |
| Date | 2nd November 1928 | |
| Attached to EFCl/T2.11.28. RE VARNISHED FABRIC BOARD. TEST. | Standard Continental Bakelite. | Varnished Fabric Board. Grade 2. | Spauldings Bakelite Diresto. ---|---|---|--- Moisture absorption. | Practically nil. | About same as Cont'l bakelite. | Slightly worse than Cont'l bakelite. Compressibility. | Good. | Good. | Not observed. Leakage conductance. | None. | None. | Not observed. Machining Properties. | Good. | V.{VIENNA} fair. | Fair. Effect of acid. | Nil. | Not observed. | Nil. EFC. | ||