Someone smarter than me

[nitpicker]

Can someone explain the circles part in bottom right corner. Datum b is a plane. I know that it is a composite, but when I build the drf like the drawing, I'm not really sure about the results it is giving me. I think that the top part is basically reporting perp. I have to report out to 6 digits to even register for the bottom part. I am alot more familiar with legacy mode. So if I knew exactly what it was asking for, I would feel more confident. Is the bottom part just asking for tp of each of the 4 circles back to itself? If that's the case, would I report out 4 results. Or it is something completely different like cylindricity?

[nitpicker]

Here

[Cumofo]

Consider it as:
Form must be perfect at MMC, but as departs etc. You gain the MMC. So they make it smaller to get the MMC.
I feel cylindricity or roundness would satisfy in legacy.

[SingularitY]

The top FCF would be picking up each level of the feature as a cylinder, level and origin to plane B, pierce the cylinder adjacent to B with B, origin to that point, and true position each cylinder as normal in legacy selecting "worst axis" with MMC.
The bottom FCF is a little more difficult and I'm attaching a snippet from the standard to illustrate the concept. If you were to take a theoretically perfect cylinder at the largest diameter allowed and slid the 4 features into it like a long ring gage, and the part fit, and the diameter of each surface was also within the diameters allowable tolerance zone, then the part would be good. It's a functional check. You could get away with this by constructing a minimum circumscribed cylinder using all 4 individual cylinders together and if you dimension the diameter, as long as the diameter is less than the max allowable diameter and each individual cylinder is larger than the minimum allowed tolerance, then you know it is good. Normally, they want position numbers though. So dimension the diameter of the MC cylinder, then level and origin to that cylinder, and dimension each cylinder separately using "worst axis" with MMC. This will give you all of the variable data you should need.

[JEFMAN]

Very nice post, thanks for sharing it !

[SingularitY]

This site helps me out so much. I try and pay it forward as often as I can.

[louisd]

You could get away with this by constructing a minimum circumscribed cylinder using all 4 individual cylinders together

in order to do this, you would need to construct the cylinder from the hit values of all the cylinders combined, otherwise the demon will simply construct an axis from jut 4 point, each of the cylinder's centroids.

[SingularitY]

Yessir.
Cyl1.HIT[1..Cyl1.NUMHITS], etc
I also try and make sure the vector of each cylinder is the same to make the construction easier, otherwise I have to extract each individual circle.
If you're lucky enough to have a scanning probe, you could scan each level and you wouldn't have to extract.

[Cumofo]

in order to do this, you would need to construct the cylinder from the hit values of all the cylinders combined, otherwise the demon will simply construct an axis from jut 4 point, each of the cylinder's centroids.

YES! That's how to slay the demon! I AM BEOWULF! SLAYER OF MONSTERS! Beowulf-2.jpg