Profile w/t datums

[[Su...]]

Hello guys

I had a doubt in profile measurement.when I take a plane and give the datums as shown in fig .the characteristic icon become PINK colour.(I don't know why it's came like that).

First of all I don't have any CAD model I checked with manual probing.

I have a scenario when part is check with CAD model result will came ok.but with manual probing it's not coming properly.

Please clarify my doubts.

Thank you All

IMG_20190702_130003.jpg

[[An...]]

Create a 2D curve (8 elements) und make a rotatory fit.

[[Te...]]

To do profile to less than 3 datum features in Calypso you need to use a free form or a curve. Without a CAD you also have to make sure all your nominal values are correct.

[[De...]]

I am guessing it is a mistake, but there is no all around symbol, so that profile call out technically is only pointing to one plane.

Its probably worth mentioning that if you choose to use a 2D curve to check this, a single 2D Curve is not a valid check of profile of multiple 3D surfaces, at the very least you would need at least two 2D curves at different heights on the surfaces if you chose to go that method.

Differences between manual and CAD sounds like your nominal values for your features are incorrectly computed when you are manually picking points. You should verify your nominal values.

That said, you can do profile to two datum features in calypso without having curve or freeform - it just takes a couple extra steps.

In this case, do the following.

Scan the Corner Radii as Cylinders and the flats as Planes.

Create an alignment to K and L - use K as spatial, and L for location - leave planar rotation blank.

Create a Geometry Best Fit that allows rotation around the L Datum, use the alignment you created in the previous step.

Include all the cylinder and plane features you scanned as part of the profile as the elements used to calculate the geometry best fit.

Now create a theoretical 3d Line, and assign it the Geometry Best Fit alignment you made.

This line can now be used as a rotational datum feature in your profile call outs for each of those features.

Create Profile characteristics for each feature using K, L, and the 3D Line to lock rotation around L.

All of those profiles will use the same rotational datum and therefore meet simultaneous requirement while being allowed to 'float' to their best fit rotational alignment around L as a group.

[[Wa...]]

You will also have to include the 4 holes in your Geometry Best Fit. The profile and the holes have the same DRF.

[[De...]]

Nice catch, I hadn't noticed the holes.

That said, now that you have mentioned them, I think I would probably only best fit the holes since they are actually a tighter tolerance. Then I would require the profile to be good when the holes were best fit.