RoHS Solder and Solder tip life

[OzarkGadgets]

We manufacture electrical solenoids and have many hand solder applications. The RoHS compliant solder is becoming a nightmare and no one has yet to offer a solution.
RoHS complieant Solder tips work fine for a few hours then fail to transfer sufficient heat to melt the high tin solder. Cartidges are at temperature but tip temp has degraded severely. It appears that oxidation has formed and prevents the heat transfer.
Is there a process for cleaning / retinning these tips to extend their usefulness? Can't afford to replace tips twice a shift...Any advice / help would be appreciated.

 

[btrueblood]

Can you come back with what tip (brand, materials used) and what solder alloys you are using?

 

[OzarkGadgets]

96.5% Tin, 3% Silver....

Using Plato 44-3113 and/or HT-202X soldering tips on
the Hexacon 80 watt iron...

 

[ScottyUK]

Higher tip temperatures for the lead-free solders require much better discipline from the operator to control oxidation by the old fashioned wipe on the sponge pad. And the sponge MUST be wet - a dry sponge is useless. If the iron is in intermittent use and won't be wiped clean frequently, switch it off or back the temperature right down when it is not in use. Wipe the bit clean after using it: the fluxes in lead-free solders are more aggressive due to the poorer wetability of the lead free solders, and this coupled with the higher temperature makes the activated flux more damaging to the tip than the original rosin-based fluxes for 60/40 or Sn62-type alloys. If you are using a water-washable flux all of the above becomes more signiifcant - synthetic water-washable fluxes are much more active than the modified rosins and can quickly attack plated bits.


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Sometimes I only open my mouth to swap feet...

 

[zappedagain]

Instead of a sponge, I have long preferred a 'scraper' tip-cleaner for my soldering iron, something like a Hakko 599B. Their web-page claims it works for lead-free; I haven't tried it yet though...

http://www.hakko.com/english/products/hakko_599b.html

 

[monkeysolder]

Lead free stuff is horrible on our tips. You have to constantly wipe it on the wet sponge after every use like Scotty said, otherwise it fouls and will eat a hole through the tip eventually. I don't use the lead-free, but have managed to salvage a tip or two by "sanding" it on the abrasive ,waxy, tinning stuff that you find around solder stations.

 

[btrueblood]

Ozark,

Sorry not to get back to this post sooner. I can't see any way to avoid erosion of the tin coating/plating, given the high melting temperature of the solder. Tin is useful because it a.) oxidizes slowly, and b.) wets well to lead/tin solder. Does the tin/silver wet out to the tip okay?

My only suggestion would be to investigate a different, more "noble" metal coating (rhodium or platinum plated?). Dunno where you'd find them, nor how much of your left arm you'd have to fork over for 'em...

 

[nigelt]

Hold the bus, boys!
I have been trying to preempt this very issue, and having read these posts, I contacted Weller for comment.
From correspondence here are some points....
- solder station with more power & quicker response time may permit operation at a lower temp setting.
- increased iron plating on tips to extend life.
- an idle feature to reduce tip temp....the less time tip sends at high temp the longer it will last.

Also, lots of "good sharing" here.....

http://weller.blog.com/

Cheers,
Nigel

"You will master any feeling of inadequacy you may be having"
....from my fortune cookie @ the buffet!

 

[alternety]

I still use a real old soldering iron that has gold plated tips. Any idea how these tips will fare in the new world of solder?

 

[itsmoked]

Never heard of it. Doesn't make any sense to me. Gold is so soft I can't imagine it not rubbing off almost immediately.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[alternety]

One uses the wet sponge. The tips really last if you don't try to use an abrasive cleaning tool. In about 1962, someone used my iron when I was not around and cleaned it with a file or something - new tip needed.

By the way itsmoked, my well pump failed and I am going to put a piece of tubing down to let me use a bubbler when I replace the pump.

 

[ScottyUK]

I would be amazed if it was gold plating on your iron: gold leaches into the solder causing embrittlement, leaving the joint weak and the iron unplated. Could the gold be a thin oxidation layer? If it really is gold then I guess it is either a special iron for some really exotic solder alloy or was designed by someone who doesn't understand soldering!




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Sometimes I only open my mouth to swap feet...

 

[geekEE]

Scotty, but gold is used quite often on PCBs pads in order to provide a flat surface for BGAs. Does that cause embrittlement?

That being said, I've never seen gold plating on an iron.

 

[ScottyUK]

Agreed, but that is a very thin gold flash provided largely for pad wetability on very small geometry layouts. Gold through a wave solder machine can be a nightmare because it accumulates. Gold on a reflow line is probably much less significant. Recollections from early in my career! Typing [blue]gold embrittlement[/blue] into Google brought up a load oif hits but this one

http://www.npl.co.uk/ei/documents/gold.pdf

comes from a fairly reputable source : the National Physical Laboratory.


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Sometimes I only open my mouth to swap feet...

 

[felixc]

Solders made on gold-plated PC boards have proved to be less solid that tin-plated ones because of the embrittlement. Some application areas do not tolerate ENIG (Electroless Nickel Immersion Gold) boards.

I wonder if a platinum-plated tip would do better than the current nickel-plated ones.

 

[ScottyUK]

Thanks Felix. At least my memory hasn't totally packed in!