LubeMaster, or others who know QC (SPC charts etc..)

[lendaddy]

OK,

Like I said I wear alot of hats here and I do all our QC work as well. I have a new project for which I have to do some SPC paperwork on. You know, bs CPK over 1.33, blah blah. I have been trying out various versions of QC software that does this for a couple years and not found one I really like. Now keep in mind that I am NOT a formally trained QC professional so common sense language works best. So, what program do you use? Or what would you recommend for me?

I have used some of the Excel based programs, and to be honest they seem to assume too much of my knowledge in the area (they are too raw and not neophyte friendly if you will). All I usually need to do is enter my data and print a pretty chart for QC eye wash It's almost always the same, 30 piece sample, characteristic is length, upper and lower limits. I just want to be able to say "hey I'm doing a 30 piece sample here, here's the info and sample measurements, what's the CPK of the process?". Am I asking too much? Last program I used gave me a crazy CPK of 21.XXX when I know it should have been 1.XXX. Am I unaware of different scales or standards? In other words, is there an Fahrenheit and a Celsius in the CPK world?

Is there a good program out there for an infrequent user like myself? Money isn't really an issue if it fits my bill. Thanks

[lendaddy]

Bump for the cali late risers

[kjb]

good morning,

The most important thing is to set up your charts correctly. I recommend you to go to the URLs below and read some of the basics. It's not really rocket science.

http://www.sytsma.com/tqmtools/charts.html
http://www.isixsigma.com/st/control_charts/

Good luck, and let us know if you run into specific problems.

/ Johan

[lendaddy]

Thanks,

I admit some level of ignorance on the specifics for sure. This will make good reading. Thanks again!

[BlueSkyJaunte]

www.r-project.org

[Milu]

You may find these articles interesting


http://www.qualitydigest.com/jan98/html/spctool.html
http://www.qualitydigest.com/apr99/html/spcguide.html

You can also do a search on quality digest magazine.

http://www.qualitydigest.com/search.shtml


Then, when you're an expert, you can start faking your charts properly like half my clients do

[lendaddy]

Originally posted by Milu
You may find these articles interesting


http://www.qualitydigest.com/jan98/html/spctool.html
http://www.qualitydigest.com/apr99/html/spcguide.html

You can also do a search on quality digest magazine.

http://www.qualitydigest.com/search.shtml


Then, when you're an expert, you can start faking your charts properly like half my clients do

Way ahead of ya

But seriously, I've been doing these for years. I just never bothered to toally understand them. I get the basic ideas, but the specifics allude me.

So first a specific question. When doing a study, are subgroups ALWAYS used? I was taught the basic by an older gentleman that is no longer with us and he never mentioned it. The idea I am getting from the articles is that rather than going up to my process and snagging 30 samples/entering the data in one group/ and finally getting the CpK..........I should be doing like 6 subgroups of 5 parts taken at different times? Is this correct?

One program I have will only let me chart subgroups as opposed to one group of all the parts, so I am wondering if this is the industry standard? I (prior to this) expected to just enter the values from x parts and get a CpK number. What am I missing?

[M.D. Holloway]

lendaddy,
I use Excel and Minitab to do the number crunching. As far as software goes, here are a few ideas that my buddies at ASQ provided me a while back:

Six Sigma Software Suite, Quality America, Inc.

The Six Sigma Software Suite provides the tools you need to attain the six sigma level of process performance. This software suite contains four (4) modules including SPC-PC-IV, DOE, 7MP and Flowcharting/Cause & Effect. With the ability to share information between the four modules, you can perform multivariate regression analysis and plotting within the DOE module on SPC-PC-IV data files, convert flowcharting files to 7MP diagrams and do control charting on DOE data files. $800.00

and for a learning tool:

Total Quality Tools Software for Windows by PQ Systems:

This easy-to-use software version of the Total Quality Tools book (P697) contains detailed information on each of the 21 tools described in the book. It presents each tool in a systematic, six-step approach so that users know what to expect.

This software program teaches not only how to construct the tools, but also when to use them using clear and concise language. Included is a glossary of terms which allows users to clarify terminology or recall formulas throughout the use of the program. This system also includes a summarized pocket version of the book Total Quality Tools.
Tools Featured:
Affinity Diagram , Attributes Control Charts , Brainstorming , Capability Analysis , Cause & Effect Diagrams , Check Sheet , Control Chart Interpretation , Flow Charts , Force Field Analysis , Histograms , Nominal Group Technique , Operational Definition , Pareto Diagram , Relations Diagram , Run Chart , Sampling , Scatter Diagram , Systematic Diagram , Variables Control Charts
$90

Hope it helps.

[Milu]

No real need for sub-groups.

What you're looking at is the process, using sub groups may add a little accuracy but in real terms I doubt it.

[lendaddy]

Originally posted by Milu
No real need for sub-groups.

What you're looking at is the process, using sub groups may add a little accuracy but in real terms I doubt it.

That's what I thought, but when the program I was using would NOT chart a simple group of 30 parts I started to wonder. What it would do is find the mean of those 30 and chart it as a single point, which does me no good.