Ed,
I was able to locate John H. Blaze.
In the US Census of 1880
Page 39, Supervisor's Dist No 60, Enumeration No 895, Line 41.
159 Crompton, Worcester, MA.
John Blaze, boarder, married, age 70, occupation Blacksmith.
no wife listed at this residence.
He also shows up in the Worchester City Directory for 1878 (residing at 50 Beacon) and 1879:
And in the 1881 Worchester City Directory.
Tracing him back to England, he appears to have come from Lincolnshire, as a John Blaze, of the correct age, is recorded in the 1851, 1861 and 1871 British census. This last is a best guess, as I do not have full access to those records.
So as you stated, it appears a master blacksmith, well trained in the making of damascus was recruited and came to Worchester to impart his knowledge.
Pete