How Large Are Tolerances ??

Hi there, and a happy new year to all. :-)

As a newbie I struggle with the tolerances of measurements. Are these two PCs the same (061)?

Right side: 13½ mm between lines - 2 mm letters - 14 mm town
Left side: 12 3/4 mm between lines - 2 mm letters, boldish - 16 mm town

Neither is mentioned in PSS catalog as far as I can see, and they don't fit with special Philadelphia PCs...

Please can anyone help?
Thanks in advance
Lars

I had a conversation about this with the folks in the Precancel Stamp Society and there is a good deal of tolerance for dimensions between bars/bar thicknesses on precancels, especially with the vinyl precancel devices.

It depends on the pressure used and how constant it was. It also depends upon how worn the device is. There are several variables which factor into the spacing issues.

The guides in the PSS catalogs are just that. It's pretty much a matter of Occam's Razor. When all else has been eliminated, what is left must be the answer.

Hope this helps and good luck with precancel collecting. I love it!

I recall researching that unusual phrase when viewing the TV Medical series "House"

The most likely explanation is usually the correct explanation... but I am pretty sure that I just found four #596s.

Don

there is also L-22 and L-59 as possibilities, also the bureau coil mats are different from the sheet stamps

FWIW, I think you are channeling Sherlock Holmes rather than William of Occam. Occam's razor is the problem-solving principle that essentially states that simpler solutions are more likely to be correct than complex ones.

Gotcha! I just knew everyone would have some fun with the Occam's Razor misuse.

Hope everyone got a laugh out of it today.

It is also called; Grab the first one you can and get home in time for dinner. Occam was wrong but it is human nature and has gotten a lot of people who are innocent in trouble. Now, I have read all the Holmes "Cannon" but he was wrong to. You cannot eliminate all possibility's.

Occam's razor is the underlying principal for all scientific modelling and theory.

If you come home and find a bunch of trees knocked down in your backyard. It could be that aliens landed in your backyard and knocked them over. This is possibility. Or it could be that a thunderstorm blew through and knocked them down. This is also a possibility. But the odds are not 50/50 for either possibility; one explanation is much more likely.

Occam's razor principal is that the more likely explanation is the way to bet.
Don

At the top of page 4 of the PSS Town & Type catalog, it notes:
"...dimensions are approximate. However, vertical spacings vary, especially on Style 63 and between plates made for sheet stamps and coils."
There's a little more info in the PSS Bureau catalog, starting on page xxiii under "A NOTE ON THE ILLUSTRATIONS".

So yes, they both are style 61. Just from two different printings.
Hope that helps.

mattstef.

Good to see you on the forum!

Thanks for the nice welcome! Hopefully I can be of some help with US precancel questions. I'll try to keep an eye out for them.
Is there a way to set up notifications for when new threads come up in this section? I'm new at this...

Hi Matt
See you found the post.

I can't see how this explains the widening of the town and the bold type.

Anyhow, I shall try to read PSS-T&T again.


Thanks for joining
:-) lars

Lars -
I think you'll find the explanation in the Bureau catalog introduction. There's a good description of the difference between handset type and machine set type. Your two stamps are a good example of the difference there. While there are a few minor differences, the two types are similar enough that we group them as one for PSS identification. Plus, they were sometimes used in conjunction; the upper half of the pane with one, and the lower half with the other. See ebay item #283329746344 for a nice example of this...
Best,
Matt