Our STA engineer asked for calculating SPC for all SC's. None of our parts have any CC, but lot's of SC's.
So, there will be huge cost for calculating SPC for all SC's.
Is this really needed??

Thank you
Baris EKICI

I have always found that Initial Process studies are required on all the SC's stipulated.

They are SC's because they require increased attention and if you can't prove the your process is capable of meeting them initially you could have problems further down the road!

On top of that if the customer wants them, you will have to do them, unless you have grounds (financially not viable for example) not to do them!

I would try and offer alternatives, perhaps and increased inspection regime during production ramp up?

CC = Critical Characteristic.
SC = ?

CC = Critical Characteristic.
SC = ?

Special Characteristic

Thanks. Just clarifying. There are all kinds... Various Characteristic Types (http://elsmar.com/APQP/sld128.htm)

I'M reminded of a couple of customers that expressed a desire for capability studies on: cavity number presence; date code "correctness" (monthly date code); customer/supplier logo presence; and a few other ridiculous requirements that were labelled <SC> and/or <CC>. These features are burned into our casting molds and don't change without conscious effort and money. It took a "face-to-face" with the Design Engineer but once we had that, he understood and backed off.

If there is a financial impact (especially if they were an "afterthought" once the job was awarded) or it could delay timing of the project, I would follow Manix's advice and document the reasons for not performing studies on all of the features and address each one with your customer.

I'M reminded of a couple of customers that expressed a desire for capability studies on: cavity number presence; date code "correctness" (monthly date code); customer/supplier logo presence; and a few other ridiculous requirements that were labelled <SC> and/or <CC>. These features are burned into our casting molds and don't change without conscious effort and money. It took a "face-to-face" with the Design Engineer but once we had that, he understood and backed off.

If there is a financial impact (especially if they were an "afterthought" once the job was awarded) or it could delay timing of the project, I would follow Manix's advice and document the reasons for not performing studies on all of the features and address each one with your customer.


Just another example of a customer requesting something not understood, therefore not appropriate. As an auditor, I applaud your ability to persude them of their error.

I don't think just not doing it would suffice. I would be compelled to look for evidence of agreement with the customer.

Thank you all for your replies.
It seems SPC required for all SCs.
By the way SC means Significiant Characteristic. ( Ford acronym )
If possible I will try to change some of characteristics position from SC to YC ( Potential Significiant Characteristic )

You must also define what your SPC requirements are. There is an obvious difference between ongoing SPC and initial capability studies. As part of the PPAP requirements the SPC used in initial capability studies are usually required on all SC's (special or significant, but you are correct that Ford use Significant).

However, ongoing SPC will normally be as per YOUR requriements stated in YOUR control plan. Of course, the customer can look at your control plan and say that they want ongoing SPC on all SC's for ALL produciton batches, but again, that is something you should argue with your customer in terms of the reality of doing so.

You must also define what your SPC requirements are. There is an obvious difference between ongoing SPC and initial capability studies. As part of the PPAP requirements the SPC used in initial capability studies are usually required on all SC's (special or significant, but you are correct that Ford use Significant).

However, ongoing SPC will normally be as per YOUR requriements stated in YOUR control plan. Of course, the customer can look at your control plan and say that they want ongoing SPC on all SC's for ALL produciton batches, but again, that is something you should argue with your customer in terms of the reality of doing so.
Yes you are right, but they want both capability and ongoing SPC studies. Capability won't be a problem, it's just for one time, but SPC not.
Of course it depends on of your STA engineer. At my old company, there was no any SPC request for SC's.

Don't ya just love it?

It says at the top of the FMEA "Potential Failure Modes....."

Which means that the special characteristics are "Potential" to begin with.

Now we have YC , which makes it a "Potential Potential Significant Characteristic".:lmao:

Only with Ford........:bonk:

Of course it depends on of your STA engineer. At my old company, there was no any SPC request for SC's.

In a nutshell! A company so focused on rules and methods for doing everything, that the policing (the STA's job in some respects) becomes overwhelmed by inconsistency!

Right that's it! I am going to change the face of "Quality" forever, a pioneer in my filed, forget APQP methodology, forget Deming etc..... for I have the answer:

KISS (Keep it Simple Stupid!)

It can't fail because everyone will understand! :lol:

Even the bods at FORD, GM and DC will love it, it is another fantastically crafted play on words and letters so that it actually spells out a word! GENIUS! All hail! ;)

In a nutshell! A company so focused on rules and methods for doing everything, that the policing (the STA's job in some respects) becomes overwhelmed by inconsistency!

Right that's it! I am going to change the face of "Quality" forever, a pioneer in my filed, forget APQP methodology, forget Deming etc..... for I have the answer:

KISS (Keep it Simple Stupid!)

It can't fail because everyone will understand! :lol:

Even the bods at FORD, GM and DC will love it, it is another fantastically crafted play on words and letters so that it actually spells out a word! GENIUS! All hail! ;)


OK...but, ummm...that's what they call Lean Mfg. It's just that some people didn't keep Lean simple...