True Position or Perpendicularity

[ET50]

I have a part that looks like a box with 4 flanged conections protruding from that box. 2 are on one side and 2 are on the opposite side. Pipes with flanges connect to the flanges on the box. Currently the designer has coordinate dimensions locating the flanges with a perpendicularity call out. Wouldn't it be better to have basic dimensions with true position instead. The primary datum would control perpendicularity, and the flanges in my opinion anyway would be located more accuratly. Thanks for your help.

 

[KENAT]

Any chance of a sketch I'm not sure I follow you.

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(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[ET50]

Sorry I can't provide a sketch right now, maybe I can describe it better. Imagine a box with flanged connections protruding from it (call them pins if you like). The position of the flanges or pins must be accurate enough for mating flanges or other pins (other assemblies) to mate to them in a specific location. Rather than use coordinate dimensions and a perpendicularity callout I would think that true postion would work much better to ensure accurate location of the faces of the flanges (pins)on the box. The real life senerio is that 4 pipe assemblies need to connect to the flanges on the box. So, orientation and how far the protrude from the box is important. I wouldn't be able to provide a sketch until tomorrow sometime.