Profile form without ref

[[To...]]

I have a cone with a profileform with a tolerance of 0,02.
It has no reference.

What is the best way to do this?
My results are not very uniform and I think they should be when I look at the process in the lathe.

What I have done is making a new alignment with with the cone as z and y which will give me the location of the center axis of the cone.

I have checked both position and angularity and these give me same result. The result is something like 0,0085.

I am not able to add any pictures right now , but I will do tonight.

Hope I made myself understandable.

[[Ri...]]

I would create a Free-Form surface, and recall the feature points of the Cone. Make sure to associate the surface of the Cone with the Free-Form by selecting the surface in the CAD model window.

Then inside of the Profile characteristic, use the Free-Form as the feature to be evaluated, and tell it no datum reference frame. It will best-fit the data for you.

[[Me...]]

What happens if you do not select the surfaces when recalling into the FFS? A lot of my features that I do the recall with are created with section lines and circles so I uncheck the recalculate nominals and it seems to be logical. I did not know you're supposed to select the surfaces on the model though.

[[Ri...]]

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I believe it doesn't reference the nominals off the CAD. I could be wrong about that though. I would need to test to confirm.

[[Me...]]

Let me know because I'm worried now.

I would tend to think that since I'm using created features off the model by sectioning, the nominals directly reflect the model.

[[To...]]

I did try to do free form surface on the cone but the stylus went mad and didn't hit the cone very well. Did a lot of scan in the air instead of on the part. So angle were checked and it were perfect angle.
I will try recalling the circles from the cone into a freeform surface and linking the surface to the cone.

[[To...]]

Thank you very much for the help.

I tried evaluating the last part that ran on our CMM.
It went from a profileform with a deviation of 0.04 with base alignment as reference to 0.015 when having the CAD as reference.
So recalling features points into a free form surface, linking the free form surface to the cone and making a new alignment from the free form surface were the solution.