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Lead/Lead Free In-Line Wash and UT cleaners

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PWH

#36940

Lead/Lead Free In-Line Wash and UT cleaners | 3 October, 2005

Soon we will be manufacturing board assemblies on our SMT lines that will utilize both lead and lead free water soluable solder pastes. I have read some discussion about change-over from lead to lead-free jobs related to machine cleanliness, etc. However, I can't find much information related to in-line wash systems and ultrasonic stencil cleaners. For those of you running mixed lead/lead-free products on the same SMT line, what is your opinion and experience related to cross-contamination that might occur in D.I. wash systems and D.I. ultrasonic stencil cleaners?

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RDR

#36945

Lead/Lead Free In-Line Wash and UT cleaners | 3 October, 2005

Flux is not classified as lead or lead free. You are cleaning flux not removing solder.

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#36948

Lead/Lead Free In-Line Wash and UT cleaners | 3 October, 2005

You'll still have to dispose of filters and whatnot and recycle your water polishing system tanks as hazardous materials.

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PWH

#36951

Lead/Lead Free In-Line Wash and UT cleaners | 3 October, 2005

Yea, that seems pretty obvious to me as well but we have a customer that's not buying into running lead-free in conjunction with lead. They strongly believe that we need to install a dedicated lead-free SMT line inclusive of in-line wash system. They are telling us that their other suppliers are already making the investment in new equipment. We are having trouble convincing them that this is not necessary.

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Ken

#36957

Lead/Lead Free In-Line Wash and UT cleaners | 3 October, 2005

If that's the case, let your customer go.

I have run into this situation recently.

Q. Why do you not run a dedicated line for lead free? A. You (the customer) give less than 12 weeks forcast and expect us to have a dedicated line for your product? A. You sole-source many components that routinely cause manufacturing delays. A. You currently have low WIP and little "on the books" to justify a 1 or 2 million dollar investment. A. Not enough demand from ALL customers to justify new expenses at this time. A. Dedicated lines can be contrary to lean manufacturing and complicate scheduling the factory demand. A. Lead contamination is not a function of the SMT line. It is a function of the processes and procedures used on that line. A. When you begin scrubbing your BOM's correctly and stop undocumented substitutions where-as you contaminate my LF wave solder pot then we'll talk.

I recently went through LF qualifications from Intel. 2 day on-site survey followed by on-site visual observations during the pilot builds. Sample boards were subsequently sent for analysis where-as the constituent components (metals, ceramics and plastics are separated and analyzed for lead content. Results: Metals = pass, ceramics = pass, plastics = fail. Plastics from connectors was the culprit. This all happened on a randomly selected smt line. All of which routinely see various solder alloys.

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PWH

#36962

Lead/Lead Free In-Line Wash and UT cleaners | 4 October, 2005

Thanks for this reply - we're up against all the things you mention...

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Reflow Oven

SMT in-printer dispensing