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PCB Array Designs

PCB Array Designs

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We do not recommend array sizes. PCB houses take a single b... - Jun 05, 2007 by SWAG

We have the same situation here. But generally it is the cu... - Jun 05, 2007 by Hussman

Am I missing something? Get the Laminate Sizes from your... - Jun 05, 2007 by JAX

An example would be great, Hussman. Please send to ... - Jun 06, 2007 by SWAG

I think everyone has experienced this issue at one time or a... - Jun 06, 2007 by robgd3

Sounds familiar. We are trying to get credit for a bunch of... - Jun 06, 2007 by SWAG

You may be JAX... My purchasing people send out for quote... - Jun 06, 2007 by Hussman

SWAG

#50497

PCB Array Designs | 5 June, 2007

We do not recommend array sizes. PCB houses take a single board and turn it into a step/repeat that is best fit for their process = cheaper boards I suppose. We then approve this array and build programs and tooling to match. On occasion, we receive board arrays that are not what we approved from a specific vendor. An expample of this is an approved array where the tab routing was designed with a 3/32" endmill as shown in the gerber they sent us. We later received boards with 1/16" routing gaps. The array will not fit in our tooling as the alignment blocks are close to 3/32". Incoming QA inspection does not check for these things - they just look for details on the single boards. What are your recommendations/ideas for improving control on this issue?

Thank You -

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Hussman

#50503

PCB Array Designs | 5 June, 2007

We have the same situation here. But generally it is the customer gives us a 1-up Gerber drawing and we need a multi-up or some form of breakaway to make the product. The way we achieve this is thru a Word document we call PCB Guidelines. We attach this to our Gerber files and inform the board house to follow them. Then, our incoming people use the drill drawing for hole verification and the PCB Guidelines for any special instructions like panelization. Granted, it's not fool proof, but really helps. If you want examples i can e-mail them to you.

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JAX

#50506

PCB Array Designs | 5 June, 2007

Am I missing something?

Get the Laminate Sizes from your suppliers, and make your own Array Files. You might need to include tooling holes for the Fabrication house but they will surely supply you with the information that they need.

This way you get exactly what you want...

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SWAG

#50529

PCB Array Designs | 6 June, 2007

An example would be great, Hussman. Please send to sketest@skecorp.com if you have the time. We have something like it but maybe yours has things we didn't think of. I agree with doing our own array designs - that would be great but we are low on overhead and we all have our hands in everything; keeping additional labor out of house is best for us if possible.

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robgd3

#50532

PCB Array Designs | 6 June, 2007

I think everyone has experienced this issue at one time or another.

We receive or design one-up's, and let the board house recommend panel size. Unless there's a process specific reason for us to define the panelization. We then approve the array prior to the board house running the boards.

We also have a standard read-me file that we include with all our board orders that defines acceptable routings/scoring procedures.

In the instances where the board house has neglected our wishes, as seems to be almost inevitable, we've gone back to them and: a. scolded them severely; b. had them replace the units at their cost; c. obtained a credit from them for the lost-labor on our side for processing boards that did not meet our specification; d. moved the business to another board house.

For the most part, one round of reworking at their cost, or reimbursing me my extra cost has been sufficient to get them to actually follow the specifications that I give them.

cheers, ..rob

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SWAG

#50534

PCB Array Designs | 6 June, 2007

Sounds familiar. We are trying to get credit for a bunch of boards at this time based on the gerber we approved - not an official print by any means. Unfortunately, we are stuck with the paperwork trail and the 38 junk boards that were ruined in machine shop when the mill ate them for lunch. We usually don't have trouble with x/y-step/reapeat, it's mostly some minor modifications like using a different diameter endmill between boards or things like chamfers or holes that are messy from worn out tooling. Sometimes tough to catch at incoming. It doesn't sound too bad until I have to make a halfvast fixture for the Bridgeport, write a program and sit and tune-up 3,000 chamfers much like 3 days on a slot machine at Vegas to meet a due date but that's a different story, same supplier. Yeeaaaa...dump the supplier...that's it!!!

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Hussman

#50538

PCB Array Designs | 6 June, 2007

You may be JAX...

My purchasing people send out for quotes from 8 to 12 different board manufactures from any where in the world. Each board mfger has different Laminate Sizes. So this makes things difficult. But wait, there's more. Now each board house varies on their standard mask, type of mask finish, size of route, etc... All this makes huge differences out on the manufacturing floor. So the only way to control this is to specify everything we can, which generally a list of 12 things, so we can constantly get the same type of board. No matter who we get it from.

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