How would you go about creating the alignment for DEF? I am leveling Datum D and rotating E2 to E3 xplus. How would you origin E2 and E3? Would you create a point between them and origin that point in the X and Z?
Is there no definition/explanation of what datum E and F is on the drawing (what they consist of)?
Datum F can be the large hole in the center or the larger bolt hole of the three.
Datum E could be the rightmost bolt hole or a line through both of the bolt holes... if the line passed through both of them it would be more obvious, but they don't.
I would probably have used the larger bolt hole or the center hole by the O-ring groove as datum F and the same as you for datum E.
This is a better clip of the blueprint. I am using the large bolt hole as Datum F. I was going to create a mid point between E2 and E3 and use that to origin X and Z. So your saying to use Datum F as Datum E also? I could create an offset point with E2 and E3 to go 3.813 +Z and use that to origin X and Z?
I would seriously discuss with engineers what the heck they want here. I have seen examples of parts where half of the datums weren't needed at all. They just do this because they have no clue how GD&T works with design, manufacturing & assembly processes.
Datum targets are used, in an unconventional way though. Normally, all datum targets named as "E(number)" should be used to create datum E, but your drawing seems to throw that out of the window.
Anyway, the balloons along with the definitions should be able to tell you how the datums shall be created. For example, datum E is a line between the centerpoints of E2 and E3.
It looks like there are more explanations (not visible in the snippet).
Datum A is (probably) a plane, created by the centerpoints from holes A1, A2 and A3 (spatial, primary, origin in Z).
Datum B is a line, created by the centerpoints of A2 and A3 (rotate X around Z, secondary, origin in Y).
Datum C is a plane, created by measuring the hatched section (origin in X).
Datum D is a plane (spatial, primary, origin in Z).
Datum E is a line through E2 & E3 (rotate X around Z, secondary, origin in Y).
Datum F is "unknown", but I would create it by constructing a line perpendicular to datum E (line) through the hole E1 (origin in X).
I have to make a lot of assumptions due to the in fact that contacting the people involved would be a nightmare. I actually think they prefer when I figure it out for myself as they tend to agree. Otherwise my only contact is writing SSRs which takes days, maybe weeks. So if I were to go off on my own with this one, I would do exactly as
vpt.se is doing above. Otherwise if you have the resources of someone to talk to on how this part is being used, then I would go that route.
Since you're already clocked to datum E holes, you can origin (Y) to that line. Hole F, of course, is just X origin. Drawing would be cleaner of F were pointing at the hole, rather than being a dotted line that may bisect other things, IMO.
