The mouthpiece museum does show that hard rubber mpcs were marked with a hawkins special:Could stand for Hymie Schertzer also since Hawk played exclusively metal Links w/ that stamping
I like the statement that the facings are cut to 1/10,000 of an inch accuracy. If only that was true today... and maybe then too...From vintage Link sales literature, Hawkins Special was listed as the 6 (for both Resotone and later Slant Signatures). The catalog below is 1940. The Joe Allard facing wasn't associated with a number, so guessing it is in between a 6 and a 7 might be correct given the way it is listed in Link literature. I've seen an H.S. Tone Edge with a 6 (on the side) and without a 6 and it doesn't appear to be a unique curvature, just a tip opening.
Just like stamping an old standard ligature with a "T" makes it an official "Otto Link" ligature, it is possible to stamp any old Otto Link with an H.S. and then call it a Hawkins Special. But it seems that only the .090 tip opening was considered by Otto to me a Hawkins Special. And then there's the question of whether a Hawkins Special that has been opened up beyond .090 (#6) is still a Hawkins Special.
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