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

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


First Article

David Paluck

#9140

First Article | 6 October, 1999

Our first article inspection after machine placement can take several hours depending on the complexity of the board. The operator visually checks the board against the drawing and bill of material. I'd be interested to hear if there are any other techniques in use that take less time.

Thanks

reply »

Dave Peck

#9141

Re: First Article | 6 October, 1999

| Our first article inspection after machine placement can take several hours depending on the complexity of the board. The operator visually checks the board against the drawing and bill of material. I'd be interested to hear if there are any other techniques in use that take less time. | | Thanks |

reply »

Tony

#9142

Re: First Article | 6 October, 1999

| Our first article inspection after machine placement can take several hours depending on the complexity of the board. The operator visually checks the board against the drawing and bill of material. I'd be interested to hear if there are any other techniques in use that take less time. | | Thanks | Hi David, I worked for a contract manufacture shop of hi-mix/medium-volume assembly boards and sure It did took us a long time to come up with the first article board, specially when you don't have an inspection system.

What we found out to be very good technique on inspecting for missing parts, tomb-stone parts, shifted components and reverse components is using an inspection template. You can utilise this template to inspect 100% of your board post-reflow..

Basicaly all it is a stencil with apperture openings for all your suface mount components to be placed. Usually your stencil house can design the template for you. All you do is place the template over the top of your board and if the fixure is designed correctly all the empty spots will be covered and will only expossed components that should be placed only. If there is a component that is misplaced, the template will not sit properly into the board.

Now I am working for a large OEM and using the same technique to verify all my board including my first article boards along with an inspection vision system..

Hope this helps.

reply »


JAX

#9143

Re: First Article | 6 October, 1999

| Our first article inspection after machine placement can take several hours depending on the complexity of the board. The operator visually checks the board against the drawing and bill of material. I'd be interested to hear if there are any other techniques in use that take less time. | | Thanks | John, There is a variety of things you can do. Some companies use part code scanning to varify that the correct parts are being placed. X-ray can be used to determine whether or not the parts are being placed correctly on the board. Vision systems can do this same check prior to reflow. Templates can be used post reflow. I have even seen where only one board is built, sent to an MDA tester and verified before production starts. You will have to determine what works best for your company. There are drawbacks to all of these, you might even want to mix and match to get rid of the bugs in the process. Hope I could help.

reply »

Chris May

#9144

Re: First Article | 7 October, 1999

| Our first article inspection after machine placement can take several hours depending on the complexity of the board. The operator visually checks the board against the drawing and bill of material. I'd be interested to hear if there are any other techniques in use that take less time. | | Thanks | David,

A few years ago, I looked into AOI, Automatic Optical Inspection, but then it was vastly expensive and hard to justify. Now, as technology moves on, you can buy, as I have, a decent AOI system for about �30K. On inspection and rework savings, ours would pay for itself within about 13 months. These systems operate using a scanner, similar to a photocopier. You scan in a known "golden" board and then this image is compared to your WIP boards. DiagnoSYS and Contact Systems and obviously others have decent systems. I must point out though that we are a small volume/batch high value OEM so maybe these might be to restricting for you. You could always evaluate MDA's, Manufacturing Defect Analysers, which are more akin to ATE bed of nails kit with boundary scan etc; Depending on your volumes/technology/budgets one of these options should be worth a look. If you have component verification fitted do you use that for the initial run (!?).

All the best, if you need contact numbers/names for AOI please contact.

Chris.

reply »

#9145

Re: First Article | 7 October, 1999

| Our first article inspection after machine placement can take several hours depending on the complexity of the board. The operator visually checks the board against the drawing and bill of material. I'd be interested to hear if there are any other techniques in use that take less time. | | Thanks | As I see it you do this first article check to insure that all given information is converted correctly into programcode, parts are correct delivered from stock, mounted to the correct feederplace according to the program and angles and polarities are correct. Seems to me a lack of well defined processes and mistrust in data and persons involved, you should work on that as well. For the first shot I used to check for accuracy, polarity and for purposely not placed components the rest should be checked before.

m2C

Wolfgang

reply »

#9146

Re: First Article | 7 October, 1999

| Our first article inspection after machine placement can take several hours depending on the complexity of the board. The operator visually checks the board against the drawing and bill of material. I'd be interested to hear if there are any other techniques in use that take less time. | | Thanks | David,

Because we strictly use electronic data for our equipment programming our process may allow for some simplification but here's what we do. All machine programs are made in Unicam using a merge of our customers CAD and our BOM from ERP. This is sent to the floor and transferred to the machines. The process instructions are sent to our Quality department and compared to the customers requirements and bought off long before the job hits the floor. All of our machine setups are done off line so they can be bought off without taking valuable line time. Once the job comes to the floor and is set up on machines a first article is processed through the appropriate machines. At this point because all of the programs and setup's have been verified for correct part in the correct place prior to assembly and they were made electronically the only thing we have to look at is polarity. This as you can imagine goes quickly and has not failed us yet. This works for SMT through Hand load, the only problem in hand load is the human factor. We solve that with continuous inspection. Person 2 inspects person 1 and so on. Good luck and let me know what you think. Qualcon Douglas A Philbrick VP of Operations dphilbrick@qualcon1.com

reply »

Charles Morris

#9147

Re: First Article | 7 October, 1999

| | Our first article inspection after machine placement can take several hours depending on the complexity of the board. The operator visually checks the board against the drawing and bill of material. I'd be interested to hear if there are any other techniques in use that take less time. | | | | Thanks | | | | We use the same process as Doug and it works quite well. One thing you must be careful of is operator error. If the operator trims the feeder incorrectly (especially Mydatas) the wrong part will be placed on that location regardless of how accurate the program is or if all feeders are loaded correctly. First article and in process inspections have saved us many times from huge errors. Charles

reply »

Peter Loten

#9148

Re: First Article | 10 November, 2000

Chris thanks for saying nice things about Diagnosys AOI systems.There is also another way of looking for Manufacturing Defects for about the same price - �30K/40K. Single Point Flying Probe using Impedence Analysis techniques is really taking off here at the moment. If you need any help try me at ploten@diagnosys.com

reply »

Peter Loten

#9149

Re: First Article | 10 November, 2000

Some AOI machines take your pick & place data with the component reference datincluded as defining the design . This is very quick. The only time consuming area is to build up a library of visul templates of the components (but you only do it once per component type).

This way you can do first offs in a few minutes as well as current production.

reply »

Facility Closure

FPC* - Fluid Pressure Control - Dispensing Pump