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Tons of shorts on Combo process

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#68500

Tons of shorts on Combo process | 22 March, 2013

Hello guys,

I´m pretty new on pcba process and I´m writing to see if you can help me, we have combo process om pcb for UPS boards and we are facing a lot of shorts after wave the boards. We did few tests with different fluxes different profiles changed board layout and component position but we still face problems. Anybody have experience and material to share about this process? Any tips will help a lot.

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#68502

Tons of shorts on Combo process | 22 March, 2013

Hi,

I will focus on the flux one more time. Try different amount(usually more flux should give you better result). Also depends what kind of flux you are using? Water based or alchohol based? Try with another type that you are using. Check the speed of the board, the angle you attack the wave. Is you wave very turbolent? I now it is too much but all these work together and you should find the best balance to make it work good for your process. E

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#68510

Tons of shorts on Combo process | 25 March, 2013

You mentioned that you changed the layout some, and this can be essential in this type of process. If the SMT parts and TH leads have inadequate spacing on the bottom side, shorts may be inevitable (someone else will have to advise what the recommended spacing is, I'm not sure of the spec).

You'll also want to look at direction of travel across the wave, to see if shorts can be minimized with that change.

Also, the type of wave that you have can have an effect. If your wave machine has the option, you'll want to use the turbulent or chipper wave for this process, rather than the regular wave.

Cheers, ..rob

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