Unfamiliar Blueprint Symbol - Hex Symbols


Quality Manager
This came across my desk today and I don't recognize it. Has anyone come across these hex symbols on a blueprint? One group is next to the specs and the other is next to the GD&T. The only thing I've thought of so far is a bolt type call out.

Thanks for your time!



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Re: Unfamiliar blueprint symbol

Do the position that are pointed to have basic dimensions detailing location? They look similar to 'tooling points' (but not quite the same).


Quality Manager
Oddly enough they vary. One might point to a line while another seems to just indicate it's talking about a hole, generically. I've dug in a bit more with google and noticed quite a few people mentioning that sometimes the hex symbol is what they use for notes instead of a flag. One engineer saying he liked to use Flags for notes and Hexagons for revisions.

That could make sense, although in this print there is nothing that makes sense out of the numbers and letters inside the hex symbols.
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True Position

I've seen that used before to identify changes / revisions to a drawing.

The 401/402/403/404 numbers are probably 'Changed in Revision 4, first/second/third/fourth line item'. I'd look at the change block for the phosphate change and see if that makes sense.


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Normzone is on the right track, it is an inspection requirement call out. In some applications, the specifying organization uses Hexagons to specify Quality Assurance Provisions (QAPs). If you read note 1 of your drawing, it states "Interpret quality assurance provision requirements per drawing 12993884."; this will likely give you the key to interpreting the hexagon symbols and the various information contained in each of them. You should also take a good look at MIL-W-13855 which is also called out and you can get from the ASSIST database at http://quicksearch.dla.mil/ .



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Is it possible somebody intends to put a hex on the part ? Sorry, unable to maintain serious demeanor for long periods of time :notme:


Quality Manager
For those curious we came across the information from the customer. The hex has a numerical legend for each of the three spaces. 1) Characteristic number: Various numbers ranging from 1-599, different ranges meaning different things like Critical/Major/Cert Requirements/et cetera. 2) Verification Level: Different notes for 100% inspect vs sampmling, et cetera. 3) Method of Inspection: Varying letters representing Visual/Special Test Equipment/Certified Test/et cetera.

It's nice to finally have their information.
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