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Mark D. Milward

#10457

SMD Inspection and Touch-up | 23 July, 1999

There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue?

Thanks,

Mark D. Milward

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Earl Moon

#10458

Re: SMD Inspection and Touch-up | 23 July, 1999

| There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up | operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue? | | Thanks, | | Mark D. Milward | Mark,

Damn good thinking. Ain't it a dilemma? As a purest, I protest inspection people doing touchup. As one more practical, it works in most places I have worked.

In one company I "helped," the operators did their touchup after doing their thing and inspection. It worked well because of the culture and dedication of the operators. I guess the best world is when inspectors inspect then send identified touchup sites to touchup people.

Whatever works, in whatever type quality system is best. I still can't get over my puritanical feelings, as you seem unable but, again, whatever works is best.

Moonman

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Tony

#10459

Re: SMD Inspection and Touch-up | 23 July, 1999

| There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up | operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue? | | Thanks, | | Mark D. Milward | Mark, I just finished doing a time study and evaluation post-reflow. This week we started implementing rework at the end of our Fuji line for SMT only. The inspector is now inspecting and reworking anything like tombstoning, bridging and anything that doesn't require alot of rework, for example removing and replacing a QFP.

What we are trying to do is eliminating those ugly red errows that get placed all over the boards. As we know an inspector places an arrow on a defect than the board sits on a rack. Later it gets rework and fortunally the errow gets removed. Sometimes that defect doesn't get reworked and the errow travels with it until it is removed by the washer. If we are lucky that defect gets spoted by the final inspector, if not ICT will spoted but already with a ding on our ICT YIELDS.

We believe that if the inspector spots a defect imediatly rework it. Applying the Iron almost takes the same amount of time to grab the twisser, remove the errow and place it on the board.

Thanks

Tony A

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Steve

#10460

Re: SMD Inspection and Touch-up | 23 July, 1999

| There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up | operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue? | | Thanks, | | Mark D. Milward |

Mark,

One of the goals in the assembly process should be to eliminate any queue's. Ideally, the boards would flow right from SM to the next value add workcenter with no inspection or touch-up. This is possible with robust designs and capable processes.

Given less than optimized designs and/or less than capable processes or equipment, touchup is a reality. Given this, it makes more sense to train qualified assemblers to inspect and touchup in one operation. I am against having "inspectors" as a job description or separate work center (do the inspectors have to inspect the rework as well?). My experience is that most of what gets touched up really didn't need it whether spotted by an inspector or touchup person. Tombstones, missing parts, solder bridges are obvious and need to be reworked, but "insufficient, excess, not shiny, etc." more often than not are better joints before the rework than after. It takes a lot of training to get the inspectors and/or touchup people to understand the difference between a "process indicator" and a "rework".

As you know, the most important thing is to eliminate the causes of the touchup and move from 100% inspection/touchup to sampling to complete elimination of this function and reapply the labor to value added functions. Whatever you decide the inspection/touchup should be performed real time while the product is on the machines so the root causes can be identified and eliminated.

Steve

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ScottM

#10461

Re: SMD Inspection and Touch-up | 23 July, 1999

| There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up | operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue? | | Thanks, | | Mark D. Milward | REAL Inspectors are hard to find and train. The last place I worked at had no Inspector titles but they had to be certified in inspection. Whatever the title or intent, you will always need an inspection function -- how else do you do first articles? And, there will always be defects; just how many depends on the process.

I've seperated Inspectors from Assemblers simply because it's easier to train and control a few for defect detection than a whole production floor, the perverbial "this doesn't look good..." -- too many opinions. And I always have another person inspect a person's rework, saved my butt more than a few times. Class III the boards are inspected twice.

Theory or practice, you gotta do what fits your operation.

Cheers, Scott

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Bob Neverosky

#10462

Re: SMD Inspection and Touch-up | 23 July, 1999

| | There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up | | operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue? | | | | Thanks, | | | | Mark D. Milward | | | REAL Inspectors are hard to find and train. The last place I worked at had no Inspector titles but they had to be certified in inspection. Whatever the title or intent, you will always need an inspection function -- how else do you do first articles? And, there will always be defects; just how many depends on the process. | | I've seperated Inspectors from Assemblers simply because it's easier to train and control a few for defect detection than a whole production floor, the perverbial "this doesn't look good..." -- too many opinions. And I always have another person inspect a person's rework, saved my butt more than a few times. Class III the boards are inspected twice. | | Theory or practice, you gotta do what fits your operation. | | Cheers, | Scott |

Greetings! My first question is:Why are you writing people up? By writing people up, you automatically put your employees in a defensive position. They have to be perfect, or chance disciplinary action or possibly loss of employment. You might consider a little less finger pointing(unless you have a real screw up) and try making the inpsectors feel like a part of the process. By not writing people up, you can still show them when mistakes are made, and not make them feel defensive. Face it, no one likes to be put in the spotlight. Try keeping track of the errors, including the persons name, but try talking to your inpsectors as a group. Try to create within them a feeling that they are the last line of defence before the product goes out the door. It won't be easy, and it will take quite some time. But the rewards of an employee WANTING to do the best job they can far outweigh an amployee who is afraid to make a mistake.

Regards

Bob

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Steve Schrader

#10463

Re: SMD Inspection and Touch-up | 23 July, 1999

| | There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up | | operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue? | | | | Thanks, | | | | Mark D. Milward | | | REAL Inspectors are hard to find and train. The last place I worked at had no Inspector titles but they had to be certified in inspection. Whatever the title or intent, you will always need an inspection function -- how else do you do first articles? And, there will always be defects; just how many depends on the process. | | I've seperated Inspectors from Assemblers simply because it's easier to train and control a few for defect detection than a whole production floor, the perverbial "this doesn't look good..." -- too many opinions. And I always have another person inspect a person's rework, saved my butt more than a few times. Class III the boards are inspected twice. | | Theory or practice, you gotta do what fits your operation. | | Cheers, | Scott |

Scott,

To answer your question, "how else do you do first articles?" We require the machine operators to be responsible for their own work, including first article checks.

Steve

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ScottM

#10464

Re: SMD Inspection and Touch-up | 23 July, 1999

| | | There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up | | | operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue? | | | | | | Thanks, | | | | | | Mark D. Milward | | | | | REAL Inspectors are hard to find and train. The last place I worked at had no Inspector titles but they had to be certified in inspection. Whatever the title or intent, you will always need an inspection function -- how else do you do first articles? And, there will always be defects; just how many depends on the process. | | | | I've seperated Inspectors from Assemblers simply because it's easier to train and control a few for defect detection than a whole production floor, the perverbial "this doesn't look good..." -- too many opinions. And I always have another person inspect a person's rework, saved my butt more than a few times. Class III the boards are inspected twice. | | | | Theory or practice, you gotta do what fits your operation. | | | | Cheers, | | Scott | | | | | Greetings! My first question is:Why are you writing people up? By writing people up, you automatically put your employees in a defensive position. They have to be perfect, or chance disciplinary action or possibly loss of employment. You might consider a little less finger pointing(unless you have a real screw up) and try making the inpsectors feel like a part of the process. By not writing people up, you can still show them when mistakes are made, and not make them feel defensive. Face it, no one likes to be put in the spotlight. Try keeping track of the errors, including the persons name, but try talking to your inpsectors as a group. Try to create within them a feeling that they are the last line of defence before the product goes out the door. It won't be easy, and it will take quite some time. But the rewards of an employee WANTING to do the best job they can far outweigh an amployee who is afraid to make a mistake. | | Regards | | Bob | VERY good point. I've often complained about this at other places I worked at. Here I replaced a supervisor because he would punish rather than train, now some of my "worst" employees are shining stars under a good supervisor who trains and coaches on a regular basis. I don't track mistakes by operator, it's counterproductive; my Supervisors and Leads will know just by getting the "arrowed" boards back who created the problem and will act accordingly. Oh by the way, good Leads are hard to find too. Feedback is good for improvement, continuously. Mistakes are opportunities for training, if only a few minutes. It works.

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ScottM

#10465

Re: SMD Inspection and Touch-up | 24 July, 1999

| | | There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up | | | operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue? | | | | | | Thanks, | | | | | | Mark D. Milward | | | | | REAL Inspectors are hard to find and train. The last place I worked at had no Inspector titles but they had to be certified in inspection. Whatever the title or intent, you will always need an inspection function -- how else do you do first articles? And, there will always be defects; just how many depends on the process. | | | | I've seperated Inspectors from Assemblers simply because it's easier to train and control a few for defect detection than a whole production floor, the perverbial "this doesn't look good..." -- too many opinions. And I always have another person inspect a person's rework, saved my butt more than a few times. Class III the boards are inspected twice. | | | | Theory or practice, you gotta do what fits your operation. | | | | Cheers, | | Scott | | | | Scott, | | To answer your question, "how else do you do first articles?" | We require the machine operators to be responsible for their own work, including first article checks. | | Steve | I find it interesting that you think first articles are for machines only. I do a first article on EVERY new item I build be it wave solder, mechanical assembly, hand solder, first board off a push line, etc. It's amazing how a simple washer stack can go wrong, the operator thinks it's right (even though they "read" the print) but it isn't. We've also caught programming problems on the pick and place with a first article. We're a build to print shop and there aren't any detailed instructions so getting the first one right goes a long way as a sample later on. Also, some customers want to be with us when we run a first article who "insist" on a separate pair of eyes to review the process.

That's what I mean by "how else..."

Scott

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Boca

#10466

Re: SMD Inspection and Touch-up | 26 July, 1999

| There is a practise within the industry of an Inspector inspecting a board, and that same Inspector performing touch-up. My opinion is that the Inspection and Touch-up operations should be separate functions whereby the Inspector is not performing their own touch-up. We should have a system of checks and balances and by combining the operations we have none. A Touch-up | operator who inpects their own board has the tendency to perform unnecessary rework or touch-up for fear of being written up. Can I please get some thoughts and opinions on this issue? | | Thanks, | | Mark D. Milward | Your concern is well founded and technically right on the money. But as others have already mentioned, two seperate operations add to que time, WIP and cycle time, and opportunity for marking errors...

My two cents;

Let the 'inspection' people do limited rework. Limit them to rework tasks which require limited time and skills. We allow them to rework and 'self inspect' passive devices. Rework of larger components is put off line to people with more skills and tools. This limits the degree of rework training and reduces the opportunity for rework defect on 'harder' packages.

This has been working well for this facility.

Take care,

Boca

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