AnsweredAssumed Answered

Tricky dims to datum? HELP!!

Question asked by Ryan Hudson on Jul 20, 2010
Latest reply on Jul 23, 2010 by Paul Marsman

I am going to attempt to explain this in the best way I can - with the minimal knowledge of GD&T that I posses.


I need some input on the best way to dimension some surfaces/holes that get machined after a welding process. I just got a drawing from mfg asking how they make the part....and I don't normally handle this part type here, that guy is on vacation.


Attached is a quick drawing of the dilemma. The part has a pattern of hooks and pads that are made around an axis that isn't currently called out on the latest revision of the drawing (attached as well). The current datum that is used is off a hole that is not common to the pattern.

The first question I have is how would you accurately express that the cuts on the hooks and pads are centered along a revolving axis? I'm probably totally off on the explanation and I apologize, but I know very little about GD&T but I do know that it is very important that the hook slots and pad surfaces are consistent in each instance of the pattern. The bent part isn't controlled very well, so the machine step would ensure that the next assembly would prove out long as we can convey that to the floor.


Any and all help would be greatly appreciated. I'm sure I left something out so please ask me to clarify if you have specific questions.