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How do you handle Quality Control Issues?

TurningHead

Cast Iron
Joined
Oct 9, 2006
Location
S.E. Ohio
Question:
How do you handle Quality Control?

Background:
We are a medium size Machining and Manufacturing Shop, (about 20 full-time employees). Pay is by the hour (no piece -work) and competitive for our location, plus we still pick-up 100% of employee health insurance.
Our part quantities are generally small (1 to 10 pieces), but we do have a couple of repeat parts that we make all year long.
About 20% of our production runs are on CNC Chuckers and/or CNC Mills.
Balance of machining production is manual.
We also can shear, roll, brake, punch and weld low-carbon plate up to 1/4" thick, and manage to keep these machines busy full-time also. Works out to about 20% of our gross.
In today's market we are very fortunate to be as busy as we are, and about 25% of our guys are working 8 hours a week of overtime.

The Problem:
We make too much scrap.
Some of our employees do not seem to understand the financial impact of a scrap piece. This business is so competitive that I have found that a 10% scrap allowance is unrealistic or impossible to build into an estimate. Plus the scheduling impact can be terrible. And I guess it is obvious that if we are making one-offs, then getting replacement stock material can add delay and thus add more scheduling problems. Some of our guys are young and inexperienced, but most have enough time on-board to know better, so what do you do with them? Is this scenario common? How do I encourage our people to "take the next step" and be more responsible / careful with their work?

John
 
One way to approach things is to put a nice wall chart up with a pointer for the scrap rate and a pointer for the next round of pay raises and say, the higher the scrap pointer goes the lower the pay pointer goes.

Alternatively..............

Get the guys to do a scrap report listing why a part is scrap, point out also that there is no comeback on this, the thing is to find out WHY the part is scrap, what caused it, and how you can correct the problem so you dont get a scrap part again.
It maybe the case with expensive materials, that making or cutting a blank out of a bit of cheap mild steel to do setups on is the cure, or replacing a guys edge finder with a new one, or saying 'swallow your egos guys, if you are not sure how to do something. Ask!'

One word of caution, it must be done involving everyone without pointing fingers, be cause the guys who get singled out get even more nervous and tend to hide the scrap or worse... send it to the customer without saying anything :eek:

Boris
 
I would agree with Boris absolutely. Driving out fear and facilitating employee involvement in solving the problem is much more effective than whacking people over the head. Don't get caught trying to solve the problem for them. Make sure expectations are clear for every individual. It is surprising that many times employees don't focus on scrap because they were never told what was expected of them. One-on-one communication of expectations... do not post it on a bulletin board. The old "quality is job one" posters just make people cynical. Regards, Steve
 
Who trained them? Why are they so sloppy? New hires have got to be supervised and babysat until someone in management has evaluated them in real conditions. Bad habits that can be trained out should be. Otherwise, they hit the road.
 
First I would look to where most scrap is originating from by way of dollar value. Ten parts bent as a left hand rather than right hand at a dollar a pop deserves less attention than one part off a milling machine worth a hundred dollars.

Assuming it is the milling machine, what can be done immediately as an implemented process that gives results quickly at a relative reasonable cost?

Does it have digital readouts?
Does it have .500 backlash and making someone try to maintain a .0005 tolerance because to grind is an added cost.
Do we try to finish a part rather than roughing and then a normalize which would be a prudent path.
Do we assign work to people that is too difficult for them.
Do we measure .001 tolerance diameters with a dial caliper.
Is there sufficient equipment in the inspection dept.
Since there is probably no calibration of instruments, is everyone aware to check their own when facing close tolerances.

As the man in charge:

Be sure everyone has a calculator….and uses it.
Everyone has a can of dykem…..and every first piece is laid out…a lot cheaper to move a scratch line.
Once it is laid out YOU do a once over even with a scale.
At that time you suggest ways to process the part so the machinist doesn’t inadvertently box himself in a corner.
Does top management listen to feedback from the floor.
Correcting 3-4 hot spots for fallout will probably reduce 80% of your dollar loss…..then fine-tune the rest.

Group leaders:

One person well versed can take 2-3 people by the hand and explain the why and therefore. He is present for every step. Even a one of need not be a loss. 3-4 group leaders in charge with 2-3 men each clears up problems for half your shop. This also gives you a sense where the weak spots are and you can find ways to correct.
 
One place I worked in the boss made a profit sharing program.
It was set up on a factor determined by:
1How long you had been with the co. (makes you want stay arround)
2 How many days worked. (stopped people being off on Monday)
3 The amount of scrap being produced. This affected everyones dollar amount in the profit share, so it encouraged everyone to lower scrap
This worked very well because everyone was affected by one operations scrap rate.
We "encouraged" everyone to work better.
 
Pretty simple.

We had yearly bonuses of a few grand. Note I say we had.
Between whiners and scrap we had that pulled for a year then replaced by an incentive program the following year. This incentive program took our bonuses to a weekly bonus based on production, and quality. since you have short runs then you can focus on the quality. for 90% of good quality start at 10%-14.5% on the base pay as a bonus, and for 100% quality give 16% on top of they're base pay if the rest of the shop follows suit and gets at least 96% good parts. it teaches accountability for scrap due to laziess It also teaches people to work together as a team to figure things out, and help people in areas where they may have weakness, as well as the age old lesson that if the company looses then every one is going to lose cause a non profitable company can't continue to pay a good wage, and scrap won't pay a bill.

By use of that system our company had record #'s we produce a yearly average of around 95% production goals at 2 ppm scrap. A majority of the operators hit 100% every week due to keeping machine up time, tools sharp, quality detail, and working together as a team.
I can't ever hold that year of no bonus against the owner for what he has thought us from that system because it has really improved our jobs and skills and even financial well being cause when the company wins by saving on scrap, and darn near 0 defects 100% on time shipping we have really won pay wise as well.

I just hope my Boss don't read this here cause we're suppose to hate this program:)
 
That scrap drives ya nuts doesn’t it.? I know the feeling. If only my employees would pay more attention to what their doing!!
One thing I do now if possible is that I force myself not to talk to an employee about it until the next day after I’ve had a chance to settle down. Otherwise I tend to say nasty things out of my momentary anger.

Many people see this as a employee problem but its not. It’s very rare that an employee will intentionally make bad parts. You’ve got to look at this as a process problem. There is a hole in your process and scrap parts are falling through it. It’s my job to make sure that the processing is robust enough that the employee can’t make scrap parts. (as long as he/she follows the instructions of course)

One thing I’ve learned is to never attach financial rewards or punishments to scrap. This just encourages people to hide the scrap or put marginal parts in with the good ones. You’ll end up rewarding the wrong people and your customers will hand you your head. In my case I later found out the guys would take their scrap inserts and throw them in the field across the street.. Scrap count was way down, now we just had a large amount of “lost” parts.
Also be careful not to assign scrap to a person. If you’re not familiar with it I urge you to read up on Dr. Demming’s famous demonstration of scooping marbles out of a jar. Very enlightening for me especially since I was the one who seemed to continually come up with the most bad marbles. :(

I now have a table in front of the lunch room which is my “designated area for non-conforming product” (otherwise known as the scrap table). There are blank forms for all parts that that go here with boxes to be filled out for Date, Machine, Job#, Op#, Non-conforming dimension, and an area that says “What the went wrong”. Notice no operator name or Id. I don’t care who did it, I just want to make sure it doesn’t happen again. Every couple of months we have an employee free pizza and pop meeting (no beer, another lesson I’ve learned) where we go over everything on the table and discuss what happened and how to stop it from happening again. Very important not to let this turn into finger pointing. Having the parts sitting in a very visible spot gets the employees thinking about the scrap and gives them time to talk among themselves about ideas before the meeting.

Take a page from the ISO-9000 guys and fully document the processing of one of your parts. Write down every little step. Give this to your employees and ask them to list all the little things that can go wrong.

Next steal an idea from the lean manufacturing guys and do what they call a “poka-yoke”. This is basically coming up with ways to error proof the process. More importantly it’s finding low cost error proofing methods by involving the employees.
As an example say your drilling a series of holes in a part with a B-port 1 inch apart. Occasionally some one loses count of the turns on the handle and puts one in at 0.800. Someone will suggest you put digital readouts on the machine. Ok, good idea but how about something cheaper? How about scribing lines on the part? Another good idea but at today’s shop rates not very cheap. Some old guy in the back puts down his pizza and says “Heck, I just mark the table cross slide at every hole position with a felt tip marker when I make the first one and I don’t even bother counting the handle turns after that”. That’s poka-yoke.

Scrap reduction is one of those continuous improvement things. You’re never going to get to zero. You need to chart where you are now and strive to continually reduce it. Make sure you know the value of your scrap and don’t spend more fixing it than it costs.
Involve your employees but don’t get trapped in the blame game.

Oops, there I go again. Sorry for the long post. Just my 2 cents worth.
Bob
 
Update:

Once again I want to Thank You all for the help and practical information you contributed to this Thread.

Since this was posted in August we have tried to implement some of the sugestions and ideas into our shop "practice" and the results have been very good. The percent of Scrap parts being made is down and actually Productivity is up.

BTW - Some of the best suggestions: listening to feedback from the floor, Training out Bad Habits, and looking for Hot Spots then addressing them.

Regards
John
 








 
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