This is directly realted to another thread I started about Surface Finish Capability http://elsmar.com/Forums/showthread.php?t=26288
I'm wonder what practice is out there.
In my particular application I don't see why it can't be an attribute.
As long as the surface finish is below, say, 64Ra the part will be fine. It will function the same at 63 as it will at 4.
So even though I'm "measuring" why shouldn't my device be a go/no-go?
You can do attribute gauge R&R and attribute capability studies.
Please poke holes in my logic and tell me why I might be wrong.
why do I ask? because there are people out there that are demanding that if I do not meet 1.33 Cpk based on variable capability studies (see previous thread I reference) I need to do 100% inspection.
And that's really getting up my nose because I know from history that once the machine is set, barring a crash that will mess up every other characteristic on the part , I will not exceed the maximum even if the range is such that I am below even 1.00 Cpk.
AND all of the finished parts that this component goes into are 100% tested as part of hte assembly process anway!!!
(ok - that last bit was a rant, but I'm really
)
I'm wonder what practice is out there.
In my particular application I don't see why it can't be an attribute.
As long as the surface finish is below, say, 64Ra the part will be fine. It will function the same at 63 as it will at 4.
So even though I'm "measuring" why shouldn't my device be a go/no-go?
You can do attribute gauge R&R and attribute capability studies.
Please poke holes in my logic and tell me why I might be wrong.
why do I ask? because there are people out there that are demanding that if I do not meet 1.33 Cpk based on variable capability studies (see previous thread I reference) I need to do 100% inspection.
And that's really getting up my nose because I know from history that once the machine is set, barring a crash that will mess up every other characteristic on the part , I will not exceed the maximum even if the range is such that I am below even 1.00 Cpk.
AND all of the finished parts that this component goes into are 100% tested as part of hte assembly process anway!!!
(ok - that last bit was a rant, but I'm really
)
(assuming you are measuring Ra in micro inch, not microns)