Around 1896-97 Fred began selling these same pins with a porcelain base instead of a metal one ostensibly under the same patent and marked with and Locke’s catalog of that same year. The idea was that these prevented the burning of wood insulator porcelain base idea actually added little or nothing to the overall insulation value of an insulator though. From a functional engineering stand point these pins were a bit dubious. A lightning bolt that came miles down from the sky was not about to be a power arc over an insulator once induced by the lightning’s ionized path would still make it’s way around the pin.
Pins tend to track and burn from the point of the insulator’s threads down the the threads to some degree...
where...you guessed it... the burning issue normally starts to occur. Unlike a normal wood pin the burn track goes from the cob to the pin bolt with the bolt conducting leakage current to the crossarm through the inside of the porcelain base.
These pins may have actually been mechanically weaker in some ways then a situations where there was a strong horizontal pull the cob could shatter allowing the insulator to separate from the pin as the bolt dropped down into the base itself. The one advantage of this idea was that the hole in the crossarm was much smaller then a traditional wood pin but the wood cob was certainly a mechanical weak point in the design. The cob was in compression against the base and it could slowly dry out and crack leading to mechanical failure of the pin assembly. The have personally seen on lines where porcelain pin bases were used on straight runs and insulators with strong angle side strain had metal cone bases instead of porcelain ones.
the act of making selling them similar pins. Functional or not, they were rather
manufacture. Some were also likely made under contract for various jobbers and pole line hardware manufacturers into the late 1920’s. There are numerous dry process pin bases in collections that cannot be attributed to any given manufacturer that likely came from one of these sources. Elton Gish has suggested as many as has one which matches catalog # J1460 and we know Pinco was supplying their wet process products. Elton’s base has a very characteristic Pinco mahogany glaze.
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