Edge points

Can't remember if I posted this before, but it is all about EDGE POINTS for people working on sheet metal and plastic, anything that is thin and is not "cubical" (has lots of shape)

EDGE POINTS for thin material need to have a depth set so you can control where the ball touches the edge of the part. EDGE POINT has the ability to use a SAMPLE HIT on the surface so it can control the depth, and to control the depth when the part isn't perfect. If every part was perfect, there would be no need for a SURFACE SAMPLE hit, but no part is perfect and parts vary, so your depth needs to be controlled BY the actual surface, no matter how high or low that surface is. This is the purpose behind the SURFACE SAMPLE hit.

Sounds great, right? Well, it is pretty handy, but in LOTS of cases, it is also useless! The XYZ values as well as the EDGE IJK and SURFACE IJK are calculated right at the edge. If it is a flat surface (no matter it's angle) this is fine and dandy, where the surface vector stays the same within the INDENT value used for the SAMPLE HIT. If it is a curved surface, Pcdmis does not look inboard the value of the INDENT to get a surface vector, it is still the same vector for the surface right at the edge of the part. If it is a very gentle curve, you might be all right, but if it isn't, you are looking at trouble.

To avoid this problem, program either a vector point or a surface point, roughly as far in from the edge as you want your INDENT to be, then use THAT point as a reference point for your edge point. Then it makes no difference if it is a flat surface, of if you are trying to measure the end of a capitol C.

P001       =AUTO/VECTOR POINT,SHOWALLPARAMS = YES
            THEO/1463.274,-888.157,1281.805,0.0269902,-0.9996357,0
            ACTL/1463.258,-887.557,1281.805,0.0269902,-0.9996357,0
            TARG/1463.274,-888.157,1281.805,0.0269902,-0.9996357,0
            THEO_THICKNESS = 0,RECT,SNAP = YES,$
            AUTO MOVE = NO,DISTANCE = 7
T002       =AUTO/EDGE POINT,SHOWALLPARAMS = YES
            THEO/1462.739,-888.171,1284.45,0.0340143,0.0010004,0.9994208
            ACTL/1462.723,-887.572,1284.313,0.0340143,0.0010004,0.9994208
            TARG/1462.739,-888.171,1284.45,0.0340143,0.0010004,0.9994208
            THEO_THICKNESS = 0,RECT,EDGE THEO_THICKNESS = 0,ONERROR = NO,$
            AUTO MOVE = BOTH,DISTANCE = 7,RMEAS = P001,P001,P001,MEASURE ORDER = SURFACE,$
            SURFACE NORMAL = 0.0269902,-0.9996357,0,$
            INIT = 0,PERM = 0,SPACER = 3,INDENT = 3,DEPTH = 0.3