S
SteelWoman
Demonstrating "capability" in "goalpost" world
Question (and if you reply, please talk to me like I'm a moron, my SPC skills are "decent" but not strong ) In our world of cutting steel to a certain length or width, our customers supply us with what in our world we call "goalposts" - the high and low tolerances for their cuts. As long as we hit it ANYWHERE within those goalposts the customer is happy, we are happy, all is good.
My problem is this: We have a new line and I have been dutifully gatherning data points from various production runs over a 6 month period (we tend to do very brief runs, move on to something else, then hit that same order again later when the customer needs it). Anyway, I have over 1400 data points representing a 6 month period in which the vast majority of the data points are at 31.75", with the customer specification of 31.75 to 31.875. Of course when I plug this into my statistical software, because it all hugs the min, I'm "incapable", based on it's estimation of how many times we will fail - though the reality is we have not ever failed, customer is happy, we can almost produce this stuff in our sleep now.
Our registrar is coming in a few months to add this new line to the scope of our certification, and of course she'll be looking for "capability studies." Any advice on how to present this, since we ARE capable but "statistically speaking" we aren't?
Hope that explanation makes sense and any help you can offer will keep my gray hair from going white!
Question (and if you reply, please talk to me like I'm a moron, my SPC skills are "decent" but not strong ) In our world of cutting steel to a certain length or width, our customers supply us with what in our world we call "goalposts" - the high and low tolerances for their cuts. As long as we hit it ANYWHERE within those goalposts the customer is happy, we are happy, all is good.
My problem is this: We have a new line and I have been dutifully gatherning data points from various production runs over a 6 month period (we tend to do very brief runs, move on to something else, then hit that same order again later when the customer needs it). Anyway, I have over 1400 data points representing a 6 month period in which the vast majority of the data points are at 31.75", with the customer specification of 31.75 to 31.875. Of course when I plug this into my statistical software, because it all hugs the min, I'm "incapable", based on it's estimation of how many times we will fail - though the reality is we have not ever failed, customer is happy, we can almost produce this stuff in our sleep now.
Our registrar is coming in a few months to add this new line to the scope of our certification, and of course she'll be looking for "capability studies." Any advice on how to present this, since we ARE capable but "statistically speaking" we aren't?
Hope that explanation makes sense and any help you can offer will keep my gray hair from going white!