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ROHS Line Conversion Process from leaded process

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#36482

ROHS Line Conversion Process from leaded process | 2 September, 2005

Hi I just would like to ask some assistance how to convert a line using a leaded process to a lead-free process? Is there a need for us to change any equipment? printer/reflow? Currently, we are not yet in full 100% lead-free process yet so most likely we will run a mix process in the line since we can not afford to set one line for Lead-free process and remain idle depending on production forecast. I'm planning to purchase a separate set of Squeege for printer only for Lead-Free process & separate dedicated stencil for Lead-free models use only. Would this be enough? Do we need to make a major clean-up for printer & reflow before we run Lead-free process?

Please advice?

Regards,

Pyramus

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Rob

#36484

ROHS Line Conversion Process from leaded process | 2 September, 2005

Is your oven suitable for Lead free temperatures & can it achieve a decent profile across your complete range of boards?

AOI will need to be looked at too as the joints are not as shiney.

Cheers,

Rob.

PS. Where's Thisbie?

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Wild Bill

#36597

ROHS Line Conversion Process from leaded process | 9 September, 2005

Reflow and wave flow solders have to be changed more often because of contamination. Pb free PCB's don't solder as well so you will likely have to find a new process or supplier. The higher temperatures heat soak the components so they all need to be checked (batteries especially). Make sure your current component inventory is reverse compatible with the new solder and solder paste. The reflow and wave flow machines may not be compatible with the higher temperature solders. Be thorough in every investigation because there is a lot of misinformation out there. The devil is in the details!

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Mika

#36599

ROHS Line Conversion Process from leaded process | 11 September, 2005

I agree with prior postings, but there is no perfect yes/no answers, right (left)...? Only good questions to be answered. I think it is overkill to have an extra stencil, why do you need it? (That is if you have a proper stencil cleaning equipment). Think about the % of lead (it is not only lead in the RoHS directive, but just a ref. for discussion) that is allowed on the pcba/or the finished product.

We produduce protype RoHS pcba:s and we do the following things at our mixed leaded/RoHS production areas. * Separeted and green marked refigreators for solder paste. * Separeted and green marked inspection and repair areas. * Separeted reflow profiles, that is if yor oven can handle the new RoHS profiles. * Separeted and green marked RoHS Vawe solder machine. * Separeted and green marked RoHS repair solder pot. * Trained and certififed personal for dealing with RoHs production, inspection and repair (they are not green marked... yet). * Separeted and green marked component storage areas and this is by far the most complex things we currently deal with. The MSD levels(Moisture Sensitive Devices) is now a BIG deal. How to handle and keep tracking of the floor life in an efficient way? On this one, i would like to discuess furter, but maybe I should start a new thread? Sorry for my poor english gramma & spelling. Sincerly,

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Mika

#36600

ROHS Line Conversion Process from leaded process | 11 September, 2005

I forgot to mentioned, that we produce both leaded and RoHS products in the same SMT-lines. The only thing we do; is a more trouhgfully cleaning of the stencil printing machine in beween product changeover of leaded/RoHS products. Sincerly,

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