Profile form and location

[ehais]

Hi
after performed scanning i tried to print out the profile dimension (form and location) and i got a measured value of 2.85 and the tolerance is +/- 2.5, the profile is showen as within tolerance in the "edit window".
Can anyone explane how the dimension is calculated.
thanks

[Matthew D. Hoedeman]

The 2.85 value is max to min readings. With a tol of +/-2.5, you have a 5.0 wide tolerance zone. To eliminate this confusion, convert the scan to individual points, dimension those points using XYZ & T axis, with +/-2.5 for all axis. Then, any out of tolerance sinlge points will show up BIG time.

[ehais]

Thanks

[kv802]

I have a question on a related topic...
I have a program that someone else worte, which outputs X,Y,Z and T-axis values for each point on a profile with a Surface Profile tolerance of 0.5mm.
I was asked to edit the program to output just 3 values;
The Surface Profile
The Max point using a tolerance of +/-0.25mm
The Min point using a tolerance of +/-0.25mm
How do I go about doing this? Am I on the right track to make a feature set from the points, then generate the SP on the feature set? I am not really sure.
Any ideas?

Thanks,
Keith

[rangerboat72]

The 2.85 value is max to min readings. With a tol of +/-2.5, you have a 5.0 wide tolerance zone. To eliminate this confusion, convert the scan to individual points, dimension those points using XYZ & T axis, with +/-2.5 for all axis. Then, any out of tolerance sinlge points will show up BIG time.

I'm just curious here, but should you use GAP ONLY when reporting the XYZ & T (total deviation)? One of our vendors told us that you should do that but I can't quite remember exactly what it does when you turn it on....

[Matthew D. Hoedeman]

You use the GAP ONLY function for EDGE POINTS. This handy little feature eliminates the SURFACE variation in the actual reported values of an EDGE POINT measured with a SURFACE SAMPLE hit. It acts like the SNAP point for VECTOR points. Quite handy, really, for sheet metal. You need to report the edge, but not the surface and lets say the surface is off 3mm but the trim is only off 1.1mm. If you don't use the GAP ONLY function, you will show a XYZ deviation of that 3mm, but the T will only show 1.1mm. Try explaining that to some engineer, eh? "Why is the Z off 3mm but the trim is only off 1.1?"