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Leadfree Dross in Wave Solderpot

OverTheHill

#32885

Leadfree Dross in Wave Solderpot | 25 February, 2005

I believe I read somewhere, that using leadfree solder in the wave, the dross will actually collect in the bottom of the solderpot. I can't remember where I read this (maybe a nightmarrish dream I had one night). If so, how do you remove it from the solder pot? Won't the dross clog the pumps/baffles? Anyone out there using leadfree in there wave? Please comment.

Thanks.

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#32894

Leadfree Dross in Wave Solderpot | 25 February, 2005

Your leadfree dross should float, similar to your leaded dross.

It's possible you're thinking about the process for removing excess copper from the solder pot. Following the same process, with: * Leaded solder, the copper floats. So, you scoop the copper globs from the top of the pot. * Unleaded solder, the copper sinks. So, you drain the copper sludge from the bottom of the pot.

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pmdeuel

#32914

Leadfree Dross in Wave Solderpot | 27 February, 2005

Dross is a combniation of oxides and lighter metals. It will float in all but very light density metals.

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Marc

#32955

Leadfree Dross in Wave Solderpot | 1 March, 2005

Morning All

Attended APEX this year and this quesiton came up quite a bit from users. I had some conversations with my co-workers on the wave side and others at the show.

Dross is an oxide, lighter than the metals so it floats just as pmdeuel states, just scoop it out.

Copper will sink to the bottom of a pot since it is lighter but minimal risk if the pot is hot and pumps moving the material. If you run repeated warm ups and cool downs in a short period and not run the pumps very often then the risk for copper seperation is greater.

thanks marc

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OverTheHill

#32974

Leadfree Dross in Wave Solderpot | 1 March, 2005

Thanks for clearing that up, must have been copper I was thinking about.

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#32978

Leadfree Dross in Wave Solderpot | 1 March, 2005

Marc:

You say, "Copper will sink to the bottom of a pot since it is lighter ..." Why does it sink if it's lighter? What is copper lighter than?

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Marc

#33018

Leadfree Dross in Wave Solderpot | 3 March, 2005

Sorry Dave..

Ment to say "heavy" but the phone rang, people in the office...

thanks marc

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Patrick

#33109

Leadfree Dross in Wave Solderpot | 9 March, 2005

All:

All you using a nitrogen atmospheres with your lead-free waves? If not, why not, as I would think this might have benefits vis a vis reducing dross.

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KEN

#33117

Leadfree Dross in Wave Solderpot | 9 March, 2005

It is not copper.

It is copper / nickel and other variations of copper intermetalics.

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Rob

#33120

Leadfree Dross in Wave Solderpot | 10 March, 2005

It has benefits for solderability too, but costs rather a lot of money to convert your machine & you have to buy in nitrogen on a regular basis (unless you have a generator).

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py (france)

#33125

Leadfree Dross in Wave Solderpot | 10 March, 2005

Hi all the cost of the nitrogen is lower than the cost of lead free dross, don't forget than the lead free alloy is very expensive. == maintenance be carefull with tools, with a lead bath a key can fall and float, with a lead free bath the key will sink...

This message was posted Add this forum to your site! Click to learn more. the Electronics Forum @

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Rob

#33135

Leadfree Dross in Wave Solderpot | 10 March, 2005

Hi P-Y,

Nitrogen = 15 euros per hour. Solder replenishement = 1kg per hour at 11.5 euros per hour.

Obviously there is also the labour involved in scraping off the dross.

Cheers,

Rob.

NB. For all our US friends a Euro is a strange Belgian invention to help facilitate world domination.

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OverTheHill

#33145

Leadfree Dross in Wave Solderpot | 10 March, 2005

Is a Euro "Leadfree"?

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KEN

#33150

Leadfree Dross in Wave Solderpot | 10 March, 2005

Euro's....Euro's....ah yes here it is. RoHS, Article 4....shall not contain: Hex Chromium, lead, mercury and Euro's.

I heard our sales guys telling a customer tour the other day that we were No Clean, VOC free, lead free and Euro free compliant!

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Rob

#33157

Leadfree Dross in Wave Solderpot | 11 March, 2005

1 Euro coin = Centre: Cu75 Ni25 Outer Ring: Cu75 Zn20 Ni5.

Think I'd rather go with SAC305.

& They don't even have the Queen on!

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OverTheHill

#33167

Leadfree Dross in Wave Solderpot | 11 March, 2005

Will the Euro sink or float in a leadfree solder pot?

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#33175

Leadfree Dross in Wave Solderpot | 11 March, 2005

No they will all crash and burn

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Rob

#33186

Leadfree Dross in Wave Solderpot | 12 March, 2005

Rather like the dollar has...

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