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Old 01-03-2018, 08:17 PM
steve B steve B is offline
Steve Birmingham
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Join Date: Sep 2009
Location: eastern Mass.
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Quote:
Originally Posted by Tennis13 View Post
I was just curious how high-tech it had gotten.....I mean, let's assume lasers are used in surgeries, and to make microchips etc.....like very, very precise. How far off are these "trimmed cards?" i mean, theoretically, could you trim it nanometers to polish up the edges, and still have it be the right size? I presume PSA etc aren't going down to the nanometer -- do they stop at the millimeter? I'm just curious -- just a very theoretical question, because it seems that if there is something "obvious" like this, there exists a spectrum in which something moves from "covert" to "obvious" and I wonder if there is a quantifiable point in which that occurs? Does that make sense?
Well,

Obvious would be scissors. I have a couple T206s that were cut down ages ago so someone could get then to fit a page. And that's even more common on stuff like E90-1s. Really easy to tell since most people can't cut straight for as much as an inch. (Both a sad and fortunate thing all at once I suppose)

Less obvious is exacto knife type trims. Usually intended to be deceptive. They don't duplicate any traits of a real cut. I have a couple T206s trimmed this way too. One is pretty obvious, another less so, but mistakes were made by whoever trimmed it. Even if they hadn't, it would be identifiable as trimmed.

I don't know for sure if I have any laser trimmed. The edge from that is also far different then you'd get from other cutters. And most hobby level laser cutters have fairly wide beams that leave scorching. Maybe some high end machine that does it's thing in a vacuum? But that would still leave a different edge quality under magnification.

There are a few methods that could work. But at the end of the day it's a machining process, and each different process leaves different marks. Loot at enough T206s in nice condition, and you'll eventually get to being able to spot ones cut with dull blades vs sharp. Even after 107 years.

Last edited by steve B; 01-03-2018 at 08:18 PM. Reason: fixed typo
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