Perpendicularity Being Reported as Zero?

[ALousyUser]

Good morning. I am attempting to find out why my perpendicularity is being reported as zero every time I run a part. This particular perpendicularity has no diameter associated with it. See the screenshot attached.

I tried both:

Xact measure- simple plane generic feature set created from 2 sets of hits on both walls and referenced that against Datum A to find the perpendicularity.
Legacy - created a constructed midplane from 2 planes (that were created from the set of hits on each wall) and referenced that against Datum a to find the perpendicularity.

See the code below for both the generic feature set creation and the dimensions I created. Both methods came back with 0. Would anyone be able to provide some insight? It would be appreciated, thank you.

Generic Feature Set Creation

FT1 =FEAT/SET,CARTESIAN
THEO/<-8.099,1.5,5.507>,<0,0,1>
ACTL/<-8.153,1.501,5.508>,<0,0,1>
CONSTR/SET,BASIC,RR85,RR86,RR87,RR88,RR89,RR90,RR91,RR92, RR93,RR94,,
FT2 =FEAT/SET,CARTESIAN
THEO/<8.103,1.333,6.078>,<0,0,1>
ACTL/<8.092,1.333,6.088>,<0,0,1>
CONSTR/SET,BASIC,RR95,RR96,RR97,RR98,RR99,RR100,RR101,RR1 02,RR103,RR104,RR105,RR106,,
FT3 =FEAT/SET,CARTESIAN
THEO/<0.738,1.409,5.818>,<0,0,1>
ACTL/<0.708,1.409,5.824>,<0,0,1>
CONSTR/SET,BASIC,FT1,FT2,,

Both XactMeasure and Legacy Reporting

F3 =GENERIC/PLANE,DEPENDENT,CARTESIAN,$
NOM/XYZ,<FT3.TX,FT3.TY,FT3.TZ>,$
MEAS/XYZ,<FT3.X,FT3.Y,FT3.Z>,$
NOM/IJK,<1,0,0>,$
MEAS/IJK,<1,0,0>
PERP13_1 =PERPENDICULARITY : F3
FEATCTRLFRAME/SHOWPARAMS=NO,SHOWEXPANDED=NO
DIMENSION/PERPENDICULARITY,0.1,A,,
NOTE/PERP13_1
FEATURES/F3,,
DIM PERP13= PERPENDICULARITY OF PLANE PLN8,RFS TO PLANE DATUM_A,RFS UNITS=MM ,$
GRAPH=OFF TEXT=OFF MULT=10.00 OUTPUT=BOTH
AX NOMINAL MEAS +TOL -TOL DEV OUTTOL
M 0.000 0.000 0.100 0.000 0.000 0.000 #--------

[JacobCheverie]

Have you tried measuring each side of the width as a planar feature and constructing a width feature from the two?

[Schlag]

What Jacob said. I thought of that when I noticed 1 set has more "points" than the other. 2 options I would consider. do an opposing point on both walls then create a mid point. Do this as many times as you feel needed. Then take all the MIDPOINTS and create a PLN. Or create a pln on 1 side, then duplicate the hit locations on a pln on the other side, then create mid plan between the 2.

[BKulpa]

I think Schlag's method is better, constructing features rather than sets which are just collections of points.

[RandomJerk]

1) In your generic feature, you made the actual vector 1,0,0, which is exactly perpendicular to the alignment it's created in.

$ NOM/IJK,<1,0,0>,$ MEAS/IJK,<1,0,0>

2) Generic feature doesn't have a size associated with it, so even if you get the correct vector, it has no size and all you have is an angle.

3) I don't use that fancy new fangled GD&T, I stay with legacy, so I don't know that this is true for that, but constructed planes, like a midplane, have no form deviation, a factor in perpendicularity.

Id strongly recommend measuring symmetrical points on each plane, taking the midpoint of each pair, then constructing the plane from the points - this will give you a valid perpendicularity,

[SingularitY]

I agree with RandomJerk I noticed that when dimensioning perpendicularity of a midplane, the result would be zero everytime. Reason being, it's a construction (midplane) created off 2 more constructions (opposing planes.) This resulted in a midplane with no point data associated to it. Ever since then, I ALWAYS take equal and opposing points, create midpoints from opposing points, and construct a plane from those midpoints. Now the midplane has point data associated to it.
In your code, you construct 2 separate sets, then construct a set off those sets which i think would do the same thing as I described. If you cannot create equal and opposing points due to the features not allowing it, then i would create a width feature like JacobCheverie said earlier.

[DAN_M]

+1 VERY well said.

[ALousyUser]

What an incredible comment. It makes a lot of sense! Silly me. I will give this a shot. Thank you.

[vpt.se]

This^^