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Wave Solder question

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Wave Solder question - 05-/21-12 by Chris

Wave Solder question - 05-/21-12 by Carlos

Wave Solder question - 05-/22-12 by Reese

Wave Solder question - 05-/22-12 by davef

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Patrick Bruneel

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Patrick Bruneel

Wave Solder question - 05-/22-12 by Patrick Bruneel

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Patrick Bruneel

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Patrick Bruneel

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Reese

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Patrick Bruneel

Wave Solder question - 05-/22-12 by Reese

Wave Solder question - 05-/22-12 by Reese

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Reese

Wave Solder question - 05-/22-12 by Patrick Bruneel

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/22-12 by Chris

Wave Solder question - 05-/23-12 by Patrick Bruneel

Wave Solder question - 05-/23-12 by DeanM

Wave Solder question - 05-/23-12 by Chris

Wave Solder question - 05-/27-12 by josh

Wave Solder question - 05-/29-12 by aj

Wave Solder question - 05-/31-12 by edmaya33

Wave Solder question - 06-/01-12 by W Medley

Wave Solder question - 06-/01-12 by Chris

Wave Solder question - 06-/01-12 by W Medley

Wave Solder question | 21 May, 2012

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.

Thanks in advance

Wave Solder question | 21 May, 2012

What is the lead protrusion?

Wave Solder question | 22 May, 2012

Does the part seem to flow properly? Are your land patterns to IPC spec? It could be a design issue.

Wave Solder question | 22 May, 2012

Bridging Causes: Insufficient flux, excessive pre-heat, high conveyor speed, solder contamination [AIM Solder]

Wave Solder question | 22 May, 2012

Protrusion is 1 mm.

Patrick Bruneel

Wave Solder question | 22 May, 2012

What is the configuration of these 4 pins?
Square or inline?
o o or o o o o
o o

Wave Solder question | 22 May, 2012

Square

Patrick Bruneel

Wave Solder question | 22 May, 2012

are the briges like this (O-O) parallel to the wave or random parallel and perpendicular to the wave

Patrick Bruneel

Wave Solder question | 22 May, 2012

Forgot something how is the top fill on the connector?

Wave Solder question | 22 May, 2012

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.

Wave Solder question | 22 May, 2012

Here is a picture.

Attachments:

bridge.JPG

Patrick Bruneel

Wave Solder question | 22 May, 2012

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?

Wave Solder question | 22 May, 2012

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.

Patrick Bruneel

Wave Solder question | 22 May, 2012

A picture of the top side of the connector would be helpfull too. I assume the 2 large leads in the front are part of that connector too.

Wave Solder question | 22 May, 2012

These are the hold down clips for the connector. I'll post the top side picture asap.

Wave Solder question | 22 May, 2012

Lead spacing is probably an issue here. It would be better if your lead pattern was staggered, like the RJ-45 to the right. It appears there may not be enough flux on this part of the pcb.

Wave Solder question | 22 May, 2012

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.

Thanks

Attachments:

USB.JPG

Patrick Bruneel

Wave Solder question | 22 May, 2012

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.

Wave Solder question | 22 May, 2012

Do you have anything else on this board with a similar land pattern?

Wave Solder question | 22 May, 2012

> 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.

Wave Solder question | 22 May, 2012

I will give 90 deg turn a try, I want to say we've tried this in the past, but my memory is not what it once was, and the operators can't recall either. Thanks for the input, I'll keep you updated.

Wave Solder question | 22 May, 2012

Well no luck on the rotation, tried all directions to no avail, seemed to bridge in the same direction.

Wave Solder question | 22 May, 2012

So it went from parallel to perpendicular with regards to the wave, or it stayed parallel?

Patrick Bruneel

Wave Solder question | 22 May, 2012

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?

Wave Solder question | 22 May, 2012

Reese, no stayed perpendicular in regards to the wave, however on the 90deg clockwise turn from original(connector trailing)we had some bridging on the pins on the right in my first picture.

Wave Solder question | 22 May, 2012

Patrick, correct, no clean alcohol based. Machine is a Vitonics Delta Wave.

Patrick Bruneel

Wave Solder question | 23 May, 2012

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.

Wave Solder question | 23 May, 2012

Try trimming the leads to no more than 0.020" instead of 0.040" (1mm). The extra labor on the front end may save on the back end especially if almost all your boards have bridges in this area.

Wave Solder question | 23 May, 2012

Patrick and Dean, I'll try both suggestions in the next day or two and let you know what I find.

Wave Solder question | 27 May, 2012

I would suggest that the pad size vs lead length vs lead pitch are helping cause issue if rest of PCB is ok

From DFM , yes reducing lead length - experiement or reducing pad diameter could help.

Also flux can still be issue, try fluxing part prior to fluxing in machine manually - then run...

Also I have founc activity of fluxes can vary and seen issues like this dissapear by useing a higher activity flux - newer VOC-Free NC fluxes can be good here vs typical solvent based.

Wave Solder question | 29 May, 2012

spacing is very tight but you should be able to get it right...

If possible try and run it at 45 degrees over the wave and see how you get on...

we had a similar problem and this improved things dramatically ( but we had a selective pallet that was mounted in a carrier to allow this rotation)...

Wave Solder question | 31 May, 2012

Yes, 45 degree will kill the shadowing effect.
YOu can also consider the teardrop on its land.
No need to tilt to 45 degree.

Wave Solder question | 1 June, 2012

Try a simple solder mask. I use Chemtronics. A bottle is only arond $20 and is as easy to apply as it is to remove. A cheap, quick fix.

Wave Solder question | 1 June, 2012

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.

Thanks for all the suggestions

Wave Solder question | 1 June, 2012

Perhaps apply the through hole part, solder mask only one barrel. Then hand solder that single leg.

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