Seeking point densities for on-machine inspection

[dcopps]

I am seeking standards or specs that will answer the question, "How many points are required to be able to inspect and specify a surface?" I am interested in on-machine inspection, although info relating to coordinate measuring machines (CMMs) might provide a hint. I have access to ASME Y14.5 (Dimensioning and Tolerancing) but that does not specifically address this issue (or I haven't found it, if it does). Ultimately, I want to obtain an accurate assessment of surface profile variations.

Thank you.

Dale C.
Library manager

 

[NomLaser]

3 points define a plane or surface. How accurate do you want it?

 

[dcopps]

NomLaser,

Thanks for the note. My engineer tells me this is not going to do it, and asked me to say that we are talking about a spline curve profile here, not a planar surface.

-Dale

 

[NomLaser]

I'll suggest that you try in the GD&T forum. I'm sure that you will receive your answer there.

http://www.eng-tips.com/threadminder.cfm?pid=1103

 

[dcopps]

Thanks, I will try there.

 

[ewh]

I don't want to add to any confusion, but I think that forum286 may be a better place for this question.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[NomLaser]

Good point. Didn't realize that they had their own forum

 

[dcopps]

There are a sometimes bewildering array of forums on this great site. I will try this one, too, if nothing comes out of the GD&T forum. Thanks.!

-Dale