Alignment of Gear part

Maybe...

A-B as primary (level)
D-E as secondary (rotation)

A-B as X,Y origin
C as Z origin

Which would give you a [A-B | D-E | C ] alignment... yes, the order of the datums in the original DRF does not compute.

A-B - cylinder, locks two directions and two coordinates
C - plane, can't lock direction as it's the same as A-B, locks the final coordinate
D-E - line, locks the final direction (rotation)

I don't see the problem?

Thanks for your prompt reply.

I agree on your thoughts. But It is fine if we origin C plane in Z...? Like it is not following 3-2-1 alignment structure(Plane-Line-Point) and also DRF?

awaiting for your support.

Thanks

Thanks @andersl for your prompt reply.

As you said,
If we lock C plane in Z axis without locking its direction, then how we supposed to lock its rotation after leveling?

Also for D-E line, how it possible to follow 3-2-1 then?

I am confused though.

It would be great if you can suggest idea.

Thanks

You can't create an alignment that is compatible with the primary, secondary and tertiary datums, because the DRF is wrong. Datum C and A-B is controlling the same rotation...

A more "correct" DRF would be [A-B | D-E | C ] instead of [A-B | C | D-E ].

Well, as the datums lock as many degrees of freedom they can (that are not already locked), but no more, I don't see the problem (see my edit above), C is only locking the coordinate. Ninja said the same thing as answer to a duplicate post. There is no law that the datums should be in the order level, rotate, origin - here we have level and part origin, origin, rotate.

Remember that the C plane should be measured/constructed as "tangent plane, perpendicular to A-B" (I.e. all we need is the Z coordinate of the "high point" of the plane).

@ atul01011992 - it is not a good idea to post the same question in a lot of threads - people will waste their time answering something that has already been answered/discussed elsewhere.

I'm with Anders - I don't see a problem.


I don't think it's technically correct in how it's drawn, but in this instance I think the intention is clear.

I think what's maybe throwing you is it's attempting to show the combined datums (A-B and D-E) as datums in their own right - it's not necessary and just confusing (the A-B in the top left view makes sense, the A-B in the top right view is just wrong.)

A-B is your primary - Level to this (3D line generated from A and B) and set two origins on in
C sets the origin in the remaining direction
Generate / Construct line D-E and rotate to that.

I'm not clear from your post what software you're using? Is it Camio or PC-Dmis?


Further to that, I think I understand what your issue is (and what VPT says) but if you follow the Can-May-Must way of thinking it's not a problem.


If a datum CAN control a degree of freedom, and it MAY (i.e. that degree of freedom hasn't been controlled by a preceding datum) then it MUST.


In the instance of Datum C, it MAY NOT control the leveling because it's been controlled by a previous datum, it CAN NOT control the rotation (because it's vector is co-linear with the primary datum). Hence it only controls what it can, which is an origin.

@ vpt.se - Thank you. It does works.
@ NinjaBadger - Thanks for more clarification (for understanding my concern as well).
I think it is working on (alignment discussed above like A-B for levelling, D-E for rotation and C for origining at Z).
Below is the snap of same.
I am working on CAMIO its version of PC-DMIS.


@ AndersI - I apologise. I really did not have any intend to do ask repeated question. I joined this forum day before yesterday and I was not known this before. "it is not a good idea to post the same question in a lot of threads - people will waste their time answering something that has already been answered/discussed elsewhere."


Thanks Ninja , andersl and VPT again.

Have a great day !

You can do it exactly as the drawing says, just remember that the C plane should be measured/constructed as "tangent plane, perpendicular to A-B" (I.e. all you need is the Z coordinate of the "high point" of the plane).

Thank you andersl.

I will follow same.