Hello Mark,
as TechNet is a peaceful and diplomatic forum, I nod in agreement, you are quite right. You used the right sentence 'together they will work', which gives that you are not one-eyed. It's the SPC brainwrinklers I'm afraid of, or those that use SPC without sence.  I have personally seen one area of much SPC use: wirebonding. But still: knowhow comes first, then you can apply a simplified SPC. Each factor you put into the SPC chart costs a lot, so if you can minimize the factors by radical thinking, you save money. And time. And, to be very diplomatic: if correctly done, SPC will increase your knowhow in the end.
Ingemar



Hi Ingemar,
Obviously it takes interested and concerned operators to do just about anything in manufacturing but that fact doesn't eliminate the benefits of a functional SPC program.  I worked with "bogus" SPC programs for years in various places and agree that many times companies
can get bogged down in the intellectual side of it (or do it to pacify customers).  But I was once part of a place that set up a SPC program for automatically plotting chemical analysis, allowing (forcing) the Lab Tech's to review the plotted chart prior to proceding on to another analysis.  This system, like many like it, trained as it controlled.  The program was semi-automatic in that it flagged trends, plotted Cpk and so on, then forced the operator to react.
This system was central to the manual charts dealing with output inidcators.  When compared with the input factors the program allowed some rare glimpses into true process control.  It showed reactions (measured as the output)and allowed you to easily scan for input causes. It beat waiting for scrap to generate before looking for the root causes.

I'm a big fan of SPC and believe that when engineers get behind it and find ways to make it work then they will have done a great service for their company.  Too many times engineers make up their minds that SPC won't help them and that's that - they'll never truly get behind it.  Sometimes they're right, as it isn't for all processes.  But usually they're wrong.  For most processes there are SPC features that will benefit beyond the cost to maintain it.

Clearly process knowledge is important.  No amount of SPC can take the place of that.  But together they're even better.

Mark Mazzoli

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or
847-509-9700 ext.5365
##############################################################