Process Controls


Process Cat eyes coasters with a magnifying glass to illustrate Process Controls
Control your process before it controls you!

Yes, the name “Process Controls” sounds like a boring topic…

But it can save you time, money, and aggravation.

That’s not boring, now, is it??

It’s not.

Here’s why Process Controls are important: everything on earth has inherent variation. It’s just a matter of statistics.

Sound a little abstract?  Let’s look at an example.

Rhonda is a retired nurse who now runs a business making and selling wooden items that she makes in her garage workshop.

Rhonda with Gnome-shaped wooden beer mug
One of her popular products is a Gnome-shaped wooden beer mug!

But actually, her best seller is the much cheaper wooden coaster.

That stands to reason.  People are cheap.

Anyway… recently Rhonda’s customers started reporting a problem with some of her coasters.

Two coasters of vastly different thicknesses. One isn’t even level.
They’re not all the same thickness, and some aren’t even level.

This results in people spilling their beers!

Now that’s a fair complaint.  But what could she really do about it?

Rhonda didn’t know why her coasters were coming out all different when she was following the same procedure to make all of them. But luckily, she wasn’t afraid to ask her friend Process Cat for help.

Rhonda raising her hand
Why is this happening and what can I do about it???

Well, why it’s happening is…

Random Variation

Yeah, that’s not a very satisfying answer.  But it’s true and it’s important.

Basically, everything that happens has some amount of inherent variation.  If Rhonda cuts her wood (or you mold your keychains of the Dragon Overlord or make your Hand-knitted Pants for Adults) the same way every single time, they will still not turn out exactly the same every time!

It’s true: reality is weird.

So what’s a Maker to do??

Enter Process Controls

We’ll get into a little more depth on Process Controls next time. But the basic idea is, you figure out which parameters in your making/manufacturing process are causing that unwanted variation.

And… you control them.

For example, Rhonda figures out that the temperature in her workshop is a relevant factor to how thick and how level her coasters come out.  (That’s because of the effect that ambient temperature has on the wood!)

So after talking with her friend Process Cat, she realizes that she needs to monitor and control the temperature inside her workshop because ambient temperature affects the wood, which in turn affects the way her product is shaped, which in turn affects the way her product FUNCTIONS.

On the other hand?

Rhonda’s friend Gary makes cookies.

Gary making cookies

Rhonda stops by his shop and notices that HIS product has the exact same problem as HERS:

Gary takes Process Controls too far by measuring cookies with calipers.
The cookies are of uneven thickness!!!!

So she tells Gary that he should implement process controls just like she did!


(There’s always a but)

Some variation matters and some doesn’t

It’s true!

Gary’s cookies come out at different thicknesses and most aren’t totally level.  But no one’s using Gary’s cookies as a surface to balance a drink on.  So as long as they all taste good…

Gary and Process Cat eating cookies
No one cares if the cookies are level!

Weekly Challenge:

Look for ways that you can apply Process Controls in your own business – and resist the urge to apply them where you don’t need them! Come back next time to learn how to use “Process Variability”!

M.G. Rhoads shares her deep engineering

through engaging stories that make manufacturing principles easy to use and understand.

“I show makers, inventors and entrepreneurs the secrets big companies use to run a successful manufacturing line!”

About Zattatat