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Solder Wave Dross/Dirt

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#54869

Solder Wave Dross/Dirt | 26 May, 2008

Hi mates,

I encounter a problem on PCB after going thru the LeadFree Solder Wave. It shows so much dirt or dross on the PCB surface. I have attached the picture for more details.

I have tried to scope out suspected solder dross and oxidedized solder in the pot for twice already. But still the problem will come back after a few boards.

I am using composite pallet (dark color pallet), SN100C alloy.

Any advice much appreciated

Attachments:

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aj

#54872

Solder Wave Dross/Dirt | 26 May, 2008

Hi ,

The dirt you are seeing are fibres from the wave solder pallet.

Clean the underside of the pallets aswell as cleaning the Pot.

aj...

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#54877

Solder Wave Dross/Dirt | 27 May, 2008

Also looks like there maybe an issue connected to the pallet/board not pushing the solder over the back of the nozzle properly. Maybe the wave level is slightly low so any dross that is on top off the solder wave isn't being pushed away by the pallet/board effectively. Certainly looks like there is an issue with fragments coming off the solder pallets. These can be cleaned up and a coating sprayed on them to help prevent this.

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#54888

Solder Wave Dross/Dirt | 28 May, 2008

What I can recommend is :

- clean your wave frequently, frames, etc.

- looks like you have too much dross. Do you use phosphorus pills or do you have soldering alloy with phosphorus to limit as much as possible dross creation.

- are you soldering in nitrogen atmosphere ? if not you have to take dross out very frequently.

- for me solder level was to low and you soldered with dross rather then with solder.

- clean your fluxer nozzle frequently

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#54932

Solder Wave Dross/Dirt | 31 May, 2008

looks like the board has gone through and not actually fluxed properly,trying hand applying and it should fix it. IF it still occurs put the pallet through without pcb and without flux and see what residues come off in the wave. residues you are seeing are dross as pcb is dry going through the wave. have seen it once were pcb was fluxed correctly but one half of the pcb absorbed all tbe flux causing this problem on half board only best of luck

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