Patch Scan

[John Kingston]

No CAD, first try on this. V3.263. I have a part with a Spherical Radius of 2.8775 inches. Profile of .030, form only. Is a patch scan the way to go? How do I do this? It's been a while since I've used a patch scan. (5 years!)

[Matthew D. Hoedeman]

Well, to get good numbers, you will have to use SURFACE points with minimum 3 sample hits so that it can get the correct vector to comp correctly for the ball. Now, here is the problem, are you just checking the radius or are you checking other things as well? In order for a profile dimension to work, you have to know the correct XYZ nominal for each and every point or you are just wasting your time. If you are only checking the radius, just measure it as a circle in 'learning' mode, correct the feature for the right nominals and update the touches, then look at the individual points and create vector points using those XYZIJK values and you should be good to go. You can then make a feature set and dimension the profile of it.

[John Kingston]

Just checking the radius. I decided to go to measuring as a spherical radius, figuring it'll comp. for ball and correct the vectors that way. This is one of those jobs that they've had for 2 months. Now they know I'm off tomorrow and no one else can program it. "We need to run production as we are late! Can you come in tomorrow?" NOT! This is the first St. Patrick's Day after losing one of my closest friends in January. She would be with me and I owe it to her to go out. This was a ten year tradition I refuse to break this year. (sorry, had to vent, I have cancelled vacation days before due to this crap!) They also all know why I'm going, she was our Production Manager!

[J Temmen]

If you want the correct vectors for you scan points just create a sphere of nominal size and located at X,Y,Z zero, then iges it out, then import it back in t your program. Measure the actual spherical surface and origin on it, do CAD = Part and then you can use the cad for nominals in the scan.

Sorry about your friend.

[tenndoc]

Enjoy the day John and remember the good times!

[John Kingston]

Thanks, guys. It's been rough, one of the things I've done is come here for your humor. Got the part working too!

[johnboy]

Sorry for your loss of a good friend, they are hard to find.

I think I would program a 'line' of surface points from the 'pole' to the edge, calculating the correct vectors using the known angles. Then pattern & paste the line around the pole as dense as you think you need.