I'm having an issue with a particular board we run in our wave solder. it has a USB connector with 4 pins that are 3mm x3mm square. we are constantly getting abridge across at least two of the pins, but sometimes all 4. I've run out of ideas on how to eliminate it. I've done the basic things, change flux pressure, slowed it down, sped it up, adjusted the wave. The rest of the board is fine. I will note it is on the trailing edge as it goes through the wave, and I have turned it 180 with no luck.
I can't see the fill as they are underneath the connector. As far as the direction 95% seem to be perpendicular to the wave with the occasional parallel and some all the way around(not many). I have tried altering the speed, I've played with the fluxer recipe, insured proper board temp. I'm in the process of getting a picture posted.
It sound like this connector is a serious head sink which can be solved with more preheat or slower conveyer speed. It might also be a combination of the heat sinking capability of the connector together with encapsulated flux underneath the connector. When the encapsulated flux hits the wave the flux solvent start boiling which creates a cooling effect and the flux vapors also disturb proper solder flow.
Do you hear sizzling when the connector hits the wave?
Sizzling would be hard to hear our machine has forced air preheaters along with all the other ambient noise, so I'm going to say no sizzling. I've tried really slowing the conveyor down to see if it helped, I saw no noticeable difference.
The spacing, and the length as everything else on this board solders great. As far as the amount of flux goes, I altered the fluxer recipe to both spray more and less to see if either had an effect, again nothing noticable...well less was noticable, nothing changed with more. Top side picture attached.
> Chris, > > If the short in the picture is parallel > to the wave turning the board 90Deg will solve > the issue. Because then the lagest spacing will > face the wave parallel and the smallest space > perpendicular.
Yes, good point Patrick. Hopefully the OP has enough spacing on the North-South perimeter of the pcb that will allow for board rotation.
good question Reese In addition what type of flux do you use? after seeing the board am pretty sure it's a no-clean but is the flux water based (VOC free) or solvent (alcohol based) Maybe one more question what brand and type of wave machine you use?
Since you have an alcohol based flux one more thing you can try to eliminate flux encapsulation under the connector. Is flux a board and remove when fluxed. Let the board sit for an hour to assure all solvents are evaporated and place the board in the machine (after the fluxer) solder and see if this helps.
Tried fluxing, then letting it sit for an hour and then running it through post fluxer...no bridging, only tried one board though, we're pretty busy at the wave so I have to slide things in between jobs. Also cutting the leads down also worked, but time consuming, I feel the solder mask then hand solder the part would be as efficient.