Hi guys I'm running into issues, I am trying to measure my 2way which is a round slot as a square slot. (Diamond shaped RFS Locator) It takes the points on the sides then faults out saying position out of machine stroke. Not sure what's happening can anyone suggest something different? I was considering using vector points but because the parts co-ordinate system is angled to the surface im not able to use a direct offset for the surface. Attached is a screen shot of slot settings.
I am measuring it immediately after my DCC tooling ball alignment!
It sounds like when it measures the side it is expecting a radius but actually measures a plane. It then tries to create a humongous radius from that plane.
Pick the round slot. A diamond pin (stupid idea to use them, it should be a round pin) SHOULD be centered along the width as well as the length of the slot. After picking the round slot, change to a CIRCLE, and measure it LEAST SQUARE with 4 hits and RE-MEASURE turned on. As long as your start/end angles are correct to match with the direction of the slot, the results of the circle measurement will be the center of the pin as least squares finds the 'mid-point' of the opposing points of the 4-hit circle. Use remeasure so that it will get the best hits possible.
OTHER THEN THAT (since I know someone will whine about how that isn't right) you can select the slot. Generate the slot. Then pick and generate an EDGE POINT on each flat of the slot. Now, change the THEO XYZ of the edge points to the THEO of the SLOT. Then change the STOCK THICKNESS to 1/2 of the width of the slot. Then create a mid-point between the 2 edge points, then delete the slot.
You could measure 4 lines, one on each side. Then construct 4 points where the lines intersect. Then construct 2 lines from the points so you have a cross. Now create a point where the 2 lines intersect.
NinjaBadger noticed the issue. However, you should never ever ever NEVER use canned slot cycles in any CMM software. For example, with PC-DMIS round slot, it only measures the radii, assumes form is perfect, and assumes the sides are perfectly tangent.
In real life, these assumptions are dangerous. Just break the element down into its base elements (circles or cylinders, and for the sides, planes/width or points/midpoints and formula for any bonus tolerance).
I've seen some pretty crappy diamond pins in my day, the 'corners' they take off are 100% clearance, and no way to know if they are all exact, and since they do nothing, not a good idea to base the alignment on.
Thanks for everyone's input! I haven't had to do something like this in 7 years. (Just got back on a cmm machine 4 months ago) I remember my method working, silly me. The circle Method that Mathew suggested worked great and as Matthew stated above, this diamond pin is in rough shape!