TPG Grading Process/Rules/Guidelines for graders

[steve B]

Originally Posted by jad22

I imagine cards are fabricated by the manufacturer to a certain length and width using nominal values for each. Obviously, the nominal value is not going to be hit during the entire manufacturing period so there will be some differences. Where does PSA find these tolerances? They have to know what would be considered undersized for a certain card set or are they not measuring at all? How are they are measuring? Read all sorts of posts over the years where somebody who has pulled the card from the original pack submitted it and it came back not meeting the size requirements.

Size varies a lot on most older sets, a bit less on stuff from postwar, and on many modern card sets shouldn't vary at all. It's all about the technology of the time, and the person doing the cutting.

I don't recall what PSA told me way back when they were new and I asked about 70's cards that were large or small from the factory. I'd like to say 1/64th of an inch under but since the holders were sized pretty closely no tolerance for oversize. But that was a long time ago.

That level of accuracy can be done easily with an inexpensive machinists rule. Starrett makes nice ones for under $30.
http://www.starrett.com/metrology/pr...-Rules/C304R-6

but even a cheap one is fairly accurate. 2.99

home depot machinists rule

If you're more serious, I have a digital caliper that can get within .001 in, and sort of accurately to 1/10000th. But it only costs $40-50 so I don't trust it that much.

Add a 40x loupe at under $10, and a bit of knowledge, and you're all set to detect most trimming. (Nearly all, if you act conservatively and reject any that don't seem quite "right" )