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Perforation errors
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Author:  Robinr [ Sat Aug 28, 2010 7:00 pm ]
Post subject:  Perforation errors

Dear All,

Perforator encroachments are well-known, and on the 1937 Coronation stamp occurred on most sheets, but usually only two or three holes, or five or six. The issue was only perforated on a type 5 machine.

I have an example that at a glance (in my case, without a lens) it looks like a type 6B machine has been used. Particularly interesting since this machine was used for the stop side of a sheet, and this is clearly a no-stop side.

On careful examination it is, obviously a major perforator encroachment. I would be pleased to know of any other similar examples, perhaps of a false type 6 machine?

Or maybe even other more extreme examples?

Thanks, and best wishes, Robin

(2.42 MiB)

Author:  owenmac [ Fri Nov 13, 2020 9:12 am ]
Post subject:  Re: Perforation errors

Hi Robin

Here I also have a copy of the same encroachment on the same cylinder, however, mine even with a perf guide is accurate so not quite sure.



Scan 7.jpeg
(1.09 MiB)

Author:  Robinr [ Sun Nov 29, 2020 1:14 pm ]
Post subject:  Re: Perforation errors

Hi Owen,

Wonderful to get a reply, albeit ten years later than the question. Many thanks!

Since then I have a lot more experience studying perforator encroachments and false 6B perforations, nearly all with KE8 material. Even so I can only guess a comment on your block.

The panes were perforated seven at a time, that being the maximum number of sheets the machine could safely punch through without causing cloggings. This meant that there were seven copies of every remarkable deviant perforation and these would be virtually identical.

My guess is that your block and mine are from the same batch of seven that went into the machine and received that distinctive false 6B perforation.

Cheers! Robin

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