Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


joe devaney

#11947

AOI | 14 April, 1999

I've just come back from Nepcon West and I'm just as confused about AOI as when I left. Is anyone out there really happy with their equipment and getting the results they expected? I would like to know about programming time and equipment reliability. Is it worth the trouble, or just another boat anchor? Hope to here from you. Joe Devaney

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Boca

#11948

Re: AOI | 14 April, 1999

| I've just come back from Nepcon West and I'm just as confused about AOI as when I left. Is anyone out there really happy with their equipment and getting the results they expected? I would like to know about programming time and equipment reliability. Is it worth the trouble, or just another boat anchor? Hope to here from you. Joe Devaney |

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Boca

#11949

Re: AOI | 14 April, 1999

| | I've just come back from Nepcon West and I'm just as confused about AOI as when I left. Is anyone out there really happy with their equipment and getting the results they expected? I would like to know about programming time and equipment reliability. Is it worth the trouble, or just another boat anchor? Hope to here from you. Joe Devaney | | | | We are fairly pleased with our AOI's. Ours is good for catching missing, reversed, wrong (if they're marked) components. Have to keep the managers from telling customers that they can find bad components or defective solder joints. You have to define what your expectations are.

We use CR Technology RTI 6500. It's defect catching ability is quite dependent on the quality of the template taught by the programming operator, so there is a learning curve to deal with. The operators can program a PCB in about 20 minutes, starting with centroid data in spreadsheet form to a finished program ready to run on the machine.

The machine is pretty software intensive, reliability has improved a lot with the last software rev. The mechanical system is simple and very dependable so far.

Any other questions?

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#11950

Re: AOI | 14 April, 1999

| I've just come back from Nepcon West and I'm just as confused about AOI as when I left. Is anyone out there really happy with their equipment and getting the results they expected? I would like to know about programming time and equipment reliability. Is it worth the trouble, or just another boat anchor? Hope to here from you. Joe Devaney | Someone smarter than I said that you can determine the maturity of an AOI system by counting the number of camera they've added to make the system operate. Ta. Dave F

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Nancy V

#11951

Re: AOI | 15 April, 1999

I had someone suggest that they weren't really necessary as long as your process is good. Is this just a way to help you keep an eye on your process?

I was thinking, as we set up our line, our money would be more well spent with controlling the process such as on UPC system.

Have an opinion?

Nancy

| | | I've just come back from Nepcon West and I'm just as confused about AOI as when I left. Is anyone out there really happy with their equipment and getting the results they expected? I would like to know about programming time and equipment reliability. Is it worth the trouble, or just another boat anchor? Hope to here from you. Joe Devaney | | | | | | | We are fairly pleased with our AOI's. Ours is good for catching missing, reversed, wrong (if they're marked) components. Have to keep the managers from telling customers that they can find bad components or defective solder joints. You have to define what your expectations are. | | We use CR Technology RTI 6500. It's defect catching ability is quite dependent on the quality of the template taught by the programming operator, so there is a learning curve to deal with. The operators can program a PCB in about 20 minutes, starting with centroid data in spreadsheet form to a finished program ready to run on the machine. | | The machine is pretty software intensive, reliability has improved a lot with the last software rev. The mechanical system is simple and very dependable so far. | | Any other questions? | |

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Wade Oberle

#11952

Re: AOI | 16 April, 1999

| I've just come back from Nepcon West and I'm just as confused about AOI as when I left. Is anyone out there really happy with their equipment and getting the results they expected? I would like to know about programming time and equipment reliability. Is it worth the trouble, or just another boat anchor? Hope to here from you. Joe Devaney | We purchased a VT-8000 system from Orbotech about 9 months ago and have been quite impressed. From an engineering or technical point of view, the machine can do everything it was advertised to do and then some. We are a low volume, high mix contractor and therefore programming/debugging time is a big issue. By implementing a disciplined approach to package style identification, we have been able to create a library of package types and now the AOI programs almost write and debug themselves.

Somebody made an earlier comment about the matuity of the system is measured by the number of cameras. Our system has 10 cameras and has been built and sold in Europe for about 4-5 years. There may be some truth to that comment.

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Scott Davies

#11953

Re: AOI | 20 April, 1999

| I had someone suggest that they weren't really necessary as long as your process is good. Is this just a way to help you keep an eye on your process? | | I was thinking, as we set up our line, our money would be more well spent with controlling the process such as on UPC system. | | Have an opinion? | | Nancy | I am inclined to agree with Nancy here. Far better to invest the time and cash ensuring that processes are running properly than spending it on kit which, at the end of the day, doesn't add any value to the finished product.

I would be interested to hear from any of you using this kind of equipment, what sort of payback periods did you work with when you originally put tohether a justification for the expenditure? And do you also perform In Circuit/Functional electrical testing on your finished boards?

Thanks Scott

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Wade Oberle

#11954

Re: AOI | 21 April, 1999

| | I had someone suggest that they weren't really necessary as long as your process is good. Is this just a way to help you keep an eye on your process? | | | | I was thinking, as we set up our line, our money would be more well spent with controlling the process such as on UPC system. | | | | Have an opinion? | | | | Nancy | | | I am inclined to agree with Nancy here. Far better to invest the time and cash ensuring that processes are running properly than spending it on kit which, at the end of the day, doesn't add any value to the finished product. | | I would be interested to hear from any of you using this kind of equipment, what sort of payback periods did you work with when you originally put tohether a justification for the expenditure? And do you also perform In Circuit/Functional electrical testing on your finished boards? | | Thanks | Scott | Scott, I agree with your comments if you are an OEM or other large volume producer that builds a 'mature' product and has control over the design, boards, and components. That is not our situation. We deal with lot sizes of 200 to 500 boards and supplied boards and components. The process for any particular bill of material rarely gets to a 'mature' state before they re-design the product. The payback for AOI has actually been faster than my initial calculations. We do ICT and on one board alone, there are 252 components that the ICT cannot check. This is built in lot sizes of 150 units per month. You just start to get the bugs worked out of a run and the job is over. Without AOI, we would need to 100% visual inspect this class III medical product. An inspector sees about 60% of the defects and takes 10 minutes per board. The AOI takes 60 seconds and catches 99+% of the defects. There are some false calls but they are weeded out in 15-20 seconds per board. This allows accurate and timely feedback to the production line so process improvement can occur. Also, as real estate shrinks and components are smaller, it will be more difficult to manually inspect and likely more difficult to evaluate by ICT. I know your point is 'why are you inspecting in the first place, fix the process'. That seldom is realistically possible in our unique low volume, high mix environment. We feel the AOI is part of our overall stratagy of tools to insure our customer recieves a high quality product. Regarding payback, the time saved at ICT alone will provide a payback of under 12 months. Not to mention intangables such as fewer black eyes from our customers for sending them less than perfect product. AOI may not be cost effective in all applications, but it is for us.

Wade

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#11955

Re: AOI | 21 April, 1999

| | We purchased a VT-8000 system from Orbotech about 9 months ago and have been quite impressed.

Wade: Who were the top three AOI systems that you considered? What were the things that distinguished the VT-8000 from the other systems? Where did the VT-8000 fall short from the others? Does the VT-8000 need its own tech? Or can it be operated with a trained QC type? Thanks. Dave F

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Boca

#11956

Re: AOI | 22 April, 1999

| | I had someone suggest that they weren't really necessary as long as your process is good. Is this just a way to help you keep an eye on your process? | | | | I was thinking, as we set up our line, our money would be more well spent with controlling the process such as on UPC system. | | | | Have an opinion? | | | | Nancy | | | I am inclined to agree with Nancy here. Far better to invest the time and cash ensuring that processes are running properly than spending it on kit which, at the end of the day, doesn't add any value to the finished product. | | I would be interested to hear from any of you using this kind of equipment, what sort of payback periods did you work with when you originally put tohether a justification for the expenditure? And do you also perform In Circuit/Functional electrical testing on your finished boards? | | Thanks | Scott

We are a contract shop doing high mix work, job sizes can range from 20 to 800 pieces, typical is 200 pcs. Many of our customers are in a state of continuous change regarding their designs.

The AOI is one way to 'keep an eye on the process' as Nancy mentioned. We use the AOI as an audit of the surface mount process. We ICT and functional test many products, but the job is completed in surface mount before any of them reach electrical test. An AOI gives us quicker response, so we can correct reversed 'sticks' of IC's and wrong reels loaded on a PaP.

I was not involved with the initial AOI purchase, so I can't speak to the payback used for justification. The AOI we have costs less than 100K and programs very quickly. Management actually ASKED for the PO for a second machine when we reached capacity constraints.

An AOI does not "add any value to the finished product", very true. It is much like ICT and Functional tests, which are for the most part, just process process verifiction tools also. Compared to electrical tests, we find the AOI to require no test heads, faster to program, more flexible, and can be linked closer to our key assembly process (surface mount). However, it has reduced capability to find some defects because it is only an optical system but we think it has its place.

An AOI would not be first on my list for a new startup shop, of course equipment that assembles product comes first (that value added thing). But with increased complexity due to job sizes, customer mix, or even product challenges, an AOI may be a useful tool for line setup verification and process auditing.

Thanks

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