Extracting Probing Points

[Brian B 74]

I need to measure/probe about 10 random points on a 3D cavity surface (to verify size after machining). Is there an easy way to extract those points? How would you do it? I am using a probe with a 0.250" diameter ball.

 

Thanks in advance!

[robk]

I can't help you with mastercam, but I do see that you use NX as well. In NX you could use a grip file and project a ball on the surface then extract the XYZ locations. Let me know if you need the grip files (if you don't have them) and I'll send them your way tomorrow (I'm leaving for the day). In the meantime maybe somebody else could help you as to how to do it in mastercam.

[GoetzInd]

If I am understanding what you're trying to do correctly, I would just draw lines normal to the surface then trim them to the surface you want to inspect. Shorten them the radius of you're styli if required. Hope that helps.

 

Mike

[robk]

You can't do that Mike... You would have to trig out the tangency of each point in relation to the surface. The bigger the slope, the larger the error.

[GoetzInd]

Rob,

Are you talking about the error that you would encounter with probe deflection if you came in from Z only on all probe points? I would probe normal to the surface on a individual point basis. Maybe I'm missing something. Also, what is a "Grip File" in NX?

 

Mike

[GoetzInd]

I thing I know what you're saying Rob. There would be error in a probe point using a line that was not perfectly perp. to the surface.

 

Mike

[robk]

I thing I know what you're saying Rob. There would be error in a probe point using a line that was not perfectly perp. to the surface.

Correct...

 

Also, what is a "Grip File" in NX?

Google ".grx executable" for more info.

[GoetzInd]

Ok Brian. After messin around a little bit. Your best bet in MC I think will be to use create point, dynamic, and add a a surface offset the radius of your styli. Here's what I got.

 

[Brian B 74]

Thanks for all the info. I came about getting the points I need by placing a point in an X Y plane. I then used a Surface Finish Project tool path using points as my geometry. I created a custom tool of the probe I am using so I could see that it wouldn't collide with anything. It projected the probe down to the tangent point - giving me the points I needed. Pretty simple in fact.