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Foam in the wash

Foam in the wash

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We seem to have an overwhelming amount of foam produced in t... - Jun 12, 2007 by Brian A.

The presence of agitation at an air / solution interface and... - Jun 12, 2007 by davef

Hi Davef, I noticed that you are always answering most qu... - Jun 13, 2007 by Grayman

Awwww, man, now we'll never hear the end of it. Actually,... - Jun 13, 2007 by Steve Thomas

Brian, We had similar problem in our inline wash machine ti... - Jun 13, 2007 by George

Thanks everyone for the input. I think in our case Dave was ... - Jun 13, 2007 by Brian A.

Do we puke now or masterbait? ... - Jun 13, 2007 by WaveMasterLarry

Must be one of Davef's new hires. Someone feel a vacuum? ... - Jun 13, 2007 by Real Chunks

Whatever floats your dross bucket, baby. ... - Jun 13, 2007 by Steve Thomas

"I've always dreamed of becoming a golf club." ... - Jun 13, 2007 by Hussman

"The world needs ditch-diggers too." ... - Jun 13, 2007 by Dirk Nuendyke

Interesting you say this since 99% of the people never respo... - Jun 14, 2007 by Dr Shocker

One of the most pathetic displays of arse-kissing if me ever... - Jun 14, 2007 by Chim Richalds

Brian, We've see foaming issues with our wave flux occasi... - Jun 14, 2007 by hoss67

Is the prewash water going to drain or being re-circulated? ... - Jun 14, 2007 by cman

Foam in the wash | 12 June, 2007

We seem to have an overwhelming amount of foam produced in the initial rinse portion of our wash (enough to cause it to overflow). We are using an Austin American Hydrojet Mach III Inline Cleaner. To my understanding the first rinse of the boards is done with tap water and the final rinse is done with de-ionized water. We are using a de-foamer but that only works to a point and then makes it worse. Does anyone know of a better solution for this type of problem? Maybe filter the tap water or make the whole thing de-ionized? Also we are using a clay based mask that I believe is not the correct mask for this system and is also playing a role in this.

Thanks in advance.

Me

Foam in the wash | 12 June, 2007

The presence of agitation at an air / solution interface and a foaming agent causes foaming. Most water soluable fluxes contain surficants. Surficants are foaming agents.

First, it's likely this foaming is caused by poor control of the temperature of the rinse water. Even a drop of 5*C may instigate massive foaming. Contact your flux supplier for a recommended temperature. In the meantime, we suggest a 50*C control point.

Next, as boards are cleaned, it forms water soluable soaps in the wash solution. These soaps appear as foam. This foaming may be surpressed, but only in moderation. If the soap concentration becomes too high, rinsing becomes difficult. In that case, excessive foaming is a useful warning to change the wash solution.

Grayman

Foam in the wash | 13 June, 2007

Hi Davef,

I noticed that you are always answering most questions ask by people in the electronic forum. I also noticed that your reply always hit the bulls eye.You are very good. It seems that you have the experience and the knowledged in the electronics industry. This is just a comment.

Foam in the wash | 13 June, 2007

Awwww, man, now we'll never hear the end of it.

Actually, dave's a good guy and very knowledgeable about lots of topics to boot. There's just no overselling a guy that can appreciate foamy washwater, Cambrian fossils, and a nice Hefeweizan.

Foam in the wash | 13 June, 2007

Brian, We had similar problem in our inline wash machine time ago. We checked everythin on equipment (filters, DI water purity, sprayers angle, etc). To make the long story short, we found out that the problem was caused by a new solder paste. This solder paste data sheet said "little to no foam" but for us was " a lot of foam". Maybe you want to try a different solder paste if possible.

My $0.02 George

Foam in the wash | 13 June, 2007

Thanks everyone for the input. I think in our case Dave was correct in saying the temperature was the most evident casue to our foaming problem. I found out today from our maint. techs that temp. control has been an issue recently and now we know what needs to be fixed. Thanks again.

Brian

WaveMasterLarry

Foam in the wash | 13 June, 2007

Do we puke now or masterbait?

Foam in the wash | 13 June, 2007

Must be one of Davef's new hires. Someone feel a vacuum?

Foam in the wash | 13 June, 2007

Whatever floats your dross bucket, baby.

Foam in the wash | 13 June, 2007

"I've always dreamed of becoming a golf club."

Foam in the wash | 13 June, 2007

"The world needs ditch-diggers too."

Foam in the wash | 14 June, 2007

Interesting you say this since 99% of the people never respond on what the real solution was.....

Foam in the wash | 14 June, 2007

One of the most pathetic displays of arse-kissing if me ever seen one me-self!

Foam in the wash | 14 June, 2007

Brian,

We've see foaming issues with our wave flux occasionally when running large slugs of product through the wash. We love the wave flux and changing it was not an option. Our process parameters for the wash machine we're derived via a validation for medical products and are not subject to tweaking. SO - we ended up bypassing the input solenoid valve on the final rinse so it ran continuously. With a closed loop system, this allows the machine to recover very quickly between runs of product and the foaming problem is no longer a problem.

Good Luck.

Foam in the wash | 14 June, 2007

Is the prewash water going to drain or being re-circulated? If you are re-circulating don't send all or a portion to drain (or your treatment system) even sending a small portion to drain and adding fresh will reduce foaming. You will pull more water but it will reduce foaming. Also if you add to much de-foamer it can increase the amount of foaming, weard but true. Make sure you follow the manufactures recomendations for the de-foamer.

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Foam in the wash

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