Hello everyone, on an old plan, I find the J12 standard for general tolerances. Anyone have this standard? I'm also looking for a PDF of gdi from 1980 here, to maybe find this standard in it. Thank you!
Hello,
I don't think it's a standard per se, but rather an IT... No?
By the way... D12 ?
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Hello, is that what you're looking for?
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I was wondering if it was an adjustment or a standard indeed, so it would be an adjustment, an IT you think? And J12 there is marked on the plan.
Hello
Unless I'm mistaken, the tolerances were rather js and not only J which has, it seems to me, always been used to specify the quality of a shaft or a bore (depending on the uppercase or lowercase letter).
Probably an input error in the plan.
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I think the same thing
Another link https://www.bsa-groupe.fr/uploads/TPHDguAA/documenttechnique-tolrancesdefabrication.pdf
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In my 1986 GDI, the 2 appear:
To nitpick, an adjustment is when you have 2 tolerances like H7g6.
Otherwise, it's just a way of coding tolerance.
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Hello
Yes but as much as the J to determine the tolerance of a particular rating I am fine, but in general tolerance of a plan I have a big doubt. js is on the other hand a little more common in general tolerance in old plans but from memory it was following a standard before the implementation of ISO 2768 type standards but I can be wrong 
J and Js (or j and js) are the same thing. The s was certainly added to avoid possible confusion when reproducing the plans (at the time of ammonia prints)
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Bjr. In my opinion it's more like Js12. The standards are not self-service, unfortunately. They have to be paid for. Transmitting or reproducing a standard is prohibited. I therefore advise you not to request this kind of service on any site. You will surely and easily find what you are looking for, but do it subtly. The person in charge of your Quality Department (if you have one! 
) should in theory call you to order! Good luck.
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