Soldering iron tips gone black

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Protolisk

Member
Sorry I don't know any other electronics forums. I was trying to solder some stuff onto a 8 pin socket when I realised that the tip was black. I couldn't seem to tin it and it took ages to heat up.

I figured that a new tip would cost as much as a tip cleaner or whatever that stuff that renews your tip is called. I got a sandpaper foam block and sanded some of it but it kept on coming back within the first minute of being hot enough to use. The only way I could stop it was to tin it straight away but I could never tin all of the tip in time would only be able to tin blobs on it, not the actual point. I would have to sand it a bit after every few times.

Anyway I looked on the dick smith site and it says you can get spare tips in DSE Sydney but I live in Melbourne. The soldering station I have is a T1976 does anyone know where I can get a spare tip.

Also any tips on how to keep it clean? Should I get one of those brass shaving things and should the tip always have solder on it or be tinned?
 
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tmack

Member
For what its worth Ill tell you what I do. I would use as light a gauge sandpaper as you can to make it shiny again then re-tin it. I have a small tin of soldering iron tip cleaner stuck to my soldering iron base that I use to help keep it clean. Also a small sponge works great to keep cleaning the iron as you go along. That's pretty much what I do to keep it clean and it works well for me.
 
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manuka

Senior Member
Good advice, but make that a DAMP sponge! No one told me about the old damp sponge trick when I first started electronic soldering ~50 years back,& woes like yours were common until "damp wiping" became part of the soldering technique. Highly recommended!
 
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westaust55

Moderator
The black is usually from the resin in the resin cored solder we all use.
The resin is there in the frist instance to help make the solder flow.

For a sponge, get a seaweed sponge not a foam type one. The foam ones will melt with the heat.

Agree that the sponge should also be damp for best results.

I find I need to wipe the tip regularly.
 
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BCJKiwi

Senior Member
Don't Use Sandpaper!!

All modern tips have multilayer coatings over the base core. These are quite thin and designed to resist the corrosive nature of the flux. Any sort of abrasive cleaning will remove this coating and then the core will just be eaten away rapidly.
Flux is corrosive because it's job is to clean the joint so the solder will bond. When the flux stops fuming it is spent and can't do its job, hence the recommendation to tin the tip, contact the joint to heat the joint and feed the flux/solder mix into the heated joint - not to put the solder on the iron then try to make the joint with just the solder on the tip.
Current recommendations from the manufacturers is to keep tips tinned at all times including prior to turning off. If the tip gets black, re-tin and wipe, re-tin and wipe repeatedly until it tins properly.

The damp sponge pad is standard in most soldering stations. If the iron is not in a stand, than get a stand with a pad. This will protect the iron (and yourself/bench etc from burns) and provide a stable place to keep the iron.

Most of the companies that supply soldering equipment have tech and beginner pages on their websites that give lots of good info. There are numerous other sources on the web as well.
 
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moxhamj

New Member
I'll second the "damp sponge" solution. Works great for me. It just becomes a habit in the end - grab the iron, wipe it on the sponge and then use it. Usually have to wipe both sides of the tip. Keep a small bottle of water handy to keep the sponge moist. Replace the sponge every few years.
 
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Protolisk

Member
Don't Use Sandpaper!!

All modern tips have multilayer coatings over the base core. These are quite thin and designed to resist the corrosive nature of the flux. Any sort of abrasive cleaning will remove this coating and then the core will just be eaten away rapidly.
Flux is corrosive because it's job is to clean the joint so the solder will bond. When the flux stops fuming it is spent and can't do its job, hence the recommendation to tin the tip, contact the joint to heat the joint and feed the flux/solder mix into the heated joint - not to put the solder on the iron then try to make the joint with just the solder on the tip.
Current recommendations from the manufacturers is to keep tips tinned at all times including prior to turning off. If the tip gets black, re-tin and wipe, re-tin and wipe repeatedly until it tins properly.

The damp sponge pad is standard in most soldering stations. If the iron is not in a stand, than get a stand with a pad. This will protect the iron (and yourself/bench etc from burns) and provide a stable place to keep the iron.

Most of the companies that supply soldering equipment have tech and beginner pages on their websites that give lots of good info. There are numerous other sources on the web as well.
Click to expand...
You said to keep tinning and wiping till it goes away. But what if the solder doesn't even stick to the iron anymore or should I just keep melting solder and wiping till eventually it does.

Thanks for the help But are the brass shavings better than a damp sponge and where can I get a replacement tip for the T1976 from dick smith electronics?
 
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Rickharris

Senior Member
As said above:
agree with the damp sponge and wiping the tip regularly will go a long way to keeping it silvery and clean - I find the black is often the result of leaving the iron on for a long period without use.

Once you can get some of the iron tinned then the black will slowly go. Abrasive cleaning is liable to remove the iron coating which is on the top of a copper core - The flux is corrosive to copper (thats why you use it) and the copper core will slowly get eaten away - BUT sometimes abrasive cleaning is almost they only way - The copper core will last many weeks so if you scraps it clean get a new tip or 2 or 3 on order.

On the same subject I also find that our older irons - 18 Watt Antex (The yellow handles type) struggle with lead free solder - They just don't get hot enough and a terminal of any size will cool them enough to prevent a good joint - IF you are using Lead free solder and having trouble it may be worth investing in a new Iron.
 
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Dippy

Moderator
I'll 'third' the damp sponge. In fact a very damp sponge.

I've never heard of seaweed sponge so can't comment, but I've never had a wet sponge melt before. Must be some cheap Ebay sponge. You can get special sponge material for the job. It ain't the same as the sponge you (might) clean your car with.

You used to be able to get some stuff (from Ersin?) which was a powdered solder mixed with some obnoxious fluxy chemical and abrasive powder in a pellet. When you rubbed your tip/bit in it it would lightly abrade the oxide coating and tin the tip/bit in one go. It was good, but smelly and contained lead/tin solder so it's probably illegal nowadays.

Most proper soldering iron tips are finally plated with iron , bare copper will corrode fairly quickly and you'd end up with a hollow tip. NEVER use sandpaper on a plated bit. Maybe a 1200 grit just to pentrate the oxide but you'd have to be very careful and observant and I really wouldn't recommend it.

There are various suggestions for keeping tips clean.
From new it is sometimes suggested to try tinning it as it warms up.
Or, when cold, a rubbing with Scotchbright.
Or, and I quote, "If the bit will still not tin try using Multicore Tip Tinner & Cleaner. Use only as a last resort at its aggressive nature will shorten bit life. "

Some extra info:

"Electroplating with iron enables the bit to withstand this attack for a longer period. Ultimately the plate will be breached and a replacement bit will be required, this is known as corrosion failure. The effective life of the bit is therefore very much dependant upon the activity of the flux with which it is used. The standard RMA flux will produce the longest life, whilst the highly active water-soluble flux the shortest.

It is always good practice to clean the bit by frequently wiping it on a clean, damp sponge. This will prevent contamination of the bit's surface, but only if a specialist sulphur-free sponge is used. The other major mode of bit failure is dewetting, caused by a lack of fluxing activity. Whenever the hot tip is free of molten solder a layer of hard oxide tends to form. This will prevent subsequently applied solder from flowing across the tip and wetting to it. Where this occurs the natural reaction is to turn the temperature up, which of course only makes the problem worse. "No-clean" and "rosin free" fluxes have experienced particular problems in this area. The key to reducing dewetting failures is in good maintenance actions:

Keep the tip temperature as low as possible. It has been shown experimentally 4 that tip life will decrease by 30% when the temperature is increased from 345 to 400ºC, and by 65% when raised to 455ºC. It is also worth noting that the production of flux fume is also significantly suppressed at lower temperatures.
Turn the iron off, or at least down, when not in use
Keep the bit tinned and in the stand when not in use, wipe on sponge and re-tin, before use.

Should a bit become heavily oxidised it is possible to restore it by the use of a commercial cleaning compound. These products should be used sparingly; they consist of a concentrated flux that will increase the risk of corrosion failure. The use of any kind of abrasive on the tip is to be avoided. "

Good luck, we all get the coating problem, but in my experience the better quality tips/bits are more easily cleanable.
 
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moxhamj

New Member
Are brass shavings better than a damp sponge? Probably about the same. I've used both. The sponge is less abrasive though.

It is hard to get solder to stick if there is lots of oxide around. I'm not 100% sure what the black stuff is. It probably is old resin core that is carbonised, but there is a chance it is copper oxide - ie you have gone through the iron coating and are into the copper core. In which case - time to get a new tip. Get the Sydney mob to send it down to Melb!

If the black stuff is resin you should be able to clean it off with a damp sponge. You can clean anything off a soldering iron with enough elbow grease. Even baked on plastic after drilling holes in plastic boxes using the iron. Not that I ever do that. Oh, alright. Maybe once. Oh, ok, maybe a few times.
 
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Dippy

Moderator
Maybe Iron Oxide and/or oxides of any other contaminants on the surface???

Sometimes the damp sponge method is not enough - hence the info in my pevious post.....
but NEVER use a file or sandpaper - unless you are absolutely desp and/or the tip is on it's last legs (and you have ordered a new one).

On plastics eh Doc? tsk tsk. Come on Gloom&Doom merchants, chip in with tales of woe and imminent death :)
 
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manuka

Senior Member
Well- I shudder to relate that even as recently as last Friday my best s/iron has deliberately been engaged in plastic hole boring, so as to thread thru' a supply wire. With no drill handy & being the last day/hour of a nearby school's term,it transpired as the most effective quick fix for the "take it home project" of a 10 yo. I'll now no doubt spend ages revamping the tip (which regularly does SMD level work)- naturally I didn't let him see the hack...
 
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Dippy

Moderator
Yes, the solid grey stuff is what I was on about previously. Very handy. Didn't know it was still available. Well spotted.

Lead Free: Yes, some of us do. Some of us have to. I confess to still using lead/tin on prototypes so I can set the soldering iron station at a lower temp.

I have found some makes of Pb-Free to be very agressive with some s/iron bits. Have found that a particular brand of solder to be less agressive. I won't mention it as it isn't available on Ebay. And you can buy tips claimed to be better with Pb-Free.
 
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Andrew Cowan

Senior Member
That stuff in a tin is lead free nowadays.
http://www.computronics.com.au/multicore/ttc/

I think Weller make a brand of it too. I use a damp sponge for getting ecxess solder (or bits of wire) off the tip, and the cleaner for tinning the tip.

While we're on the subject, what temperatures do people use for soldering? I tend to use about 310 decrees C for lead solder, and 350 degrees C for lead free solder.

Andrew
 
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Dippy

Moderator
Lead free grey stuff: excellent, I can safely sniff it then :)

I use roughly the same temps, though it varies on the bit size and type I'm using.
I don't know how accurate the stations I use are (Cooper/Weller and Antex). Both stations are 25W I think.

I just use the lowest I can get away with when I can do a solder in less than a second for little components.
 
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marcos.placona

Senior Member
Ahh that's the same grey stuff I'm using. It's very good, and keeps the tips very clean.

I try to use it everytime I finish a soldering process. And during soldering I just use the damp sponge.

What's the recommended temperature average for lead and lead free?

UPD: Andrew, I'm using around 300-310 for lead solder
 
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Dippy

Moderator
It depends obviously.
Specific alloy.
Specific flux.
Power of soldering iron.

As far as the station setting is concerned it will vary with tip/bit type/size.
How accurate is your station? Good make pobably pretty good.... cheapoes, dunno.

We're all in the same ballpark, so your choice looks OK. Just run it as low as possible whilst you can make a good quick solder joint.

And it may be that manufacturer's may have recommended bit temps on their Data Sheets??
 
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Michael 2727

Senior Member
Cheapest Iron tip cleaner - 105g, Aluminium, Sardine Can and a Kitchen Sponge
cut in half (the coloured ones in a pack of 5 etc) fit exactly inside the can.
Cost = < $2.00 with lunch thrown in, can't beat that.
( I like the ones in tomato sauce ):)
Fill the whole thing with water, drain off the excess, refil as nessesary.
For really stubborn black bits, lightly scrape on the lip of the AL can.

Modern Irons have coated tips as stated, Don't sand this coating off
or the tip will never be the same.

You could once get solder which had ?? % copper in it and less corrosive
flux, was called Save Bit Solder cost a little extra but didn't chew
out tips as often. Dunno what the new Lead Free options are now.

Some solder/flux gets old and crappy after sitting around for years,
if the lead is very dull it has a lot of oxide on it and is best thrown out.
Use nice shiny new, thin solder, Auto pannel beaters 3mm solder should
never be used on PCBs, shudder.
 
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BCJKiwi

Senior Member
Scotchbrite is not a good idea.

Scotchbrite is a nonwoven fabric with abrasive grit embedded in it == sandpaper.
 
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Dippy

Moderator
Scotchbrite covers a few poducts.

The usual Scotchbrite used by engineers is the green stuff which is a plastic fibre.
It is also used on non-stick pans which are slightly softer than an iron plating possibley.

Unless you rub your tip for hours I cannot see any problems at all.
Most suggestions would be a quick few light wipes, not grinding the hell out of it.
Anyway, it's up to you.

Maybe there are some versions or copies which contain an abrasive.
 
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Tricky Dicky

Senior Member
Some of the kids at our school regularly contaminate the soldering iron tips (melted pens, pencil cases and the occasional chair seat) By the time they get back to the technician some of these tips are blackened beyond the ability of the damp sponge. the brass shavings or even "the grey stuff" to effectively clean them. After years of trying to get round the problem we found careful use of the small cup-type wire brushes used with dremels and minicraft drills seem to shift the oxidisation without going through the iron carbide layer. So far we have treated several tips this way and none have cavitated which suggests the iron carbide layer is OK.

One problem we have noted with brand new replacement tips is that it is difficult to tin them and we felt this was due to some protective coating applied during manufacture. A few wipes on the brass shavings seems to solve that problem.

Richard
 
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BCJKiwi

Senior Member
Re ScotchBrite - used to be involved in the manufacture the stuff - it all has abrasives - its just a matter of how much, how big the particale size, the softness of the grit, the type of fabric, the type of resin binding it all together etc etc.

So if you use one of the very fine/soft pads you will probably be OK but then you won't have much affect on the problem.
 
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Ralpht

New Member
Since Protolisk is in Melbourne Aust, just go to any Jaycar store and ask for the tip cleaner - can't remember the name.

It about $6.00AUD and works perfectly. Jaycar city store has tons in stock, I was there last friday and saw heaps of them. I have restored several tips with this stuff and they are almost like brand new.

I am almost in the same position as Protolisk in that I have an old Royel rework station that I use rather intensively. Getting tips for it is very difficult, especially the desoldering tips and other bits for the vacuum pump and attatchments.

Hence the care needed to keep everything in good order.

NEVER sand the tips, for the reasons mentioned in previous posts.
Keep everything clean, that includes tips, solder and component leads. Yes, clean the solder and component leads before you use them.

Both the wet spong method, or the dry spring bass shavings method work well. I use the brass shavings if my tip happens to get dirty - molten plastic on it or if left on hi temp for too long. The brass will gently abrade the tip without damaging it, then when clean I use the wet sponge method.
When I used to tech high reliability hand soldering in the RAAF, I always recomended that tip temp should be 320 - 340deg depending on the size of the joing being soldered.

As you place a hot tip against a colder component lead and solder, some heat will initially be removed from the tip. If you run the iron too "cool" that may be enough heat reduction to cause cold joints.
This heating - cooling - heating cycle also promotes the formation of the black crud that forms on tips if not cleaned regularly.

The soldering iron / tip must have the ability to very quickly recover from the heat loss, to prevent a poor joint being formed.

It may not be important in a hobby project where it doesn't really have to last long, but in a military/commercial environment reliability is a major concern.
 
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BeanieBots

Moderator
A soldering iron tip is a bit like a fountain pen nib in as much as it becomes personalised to your way of soldering/(writing) and should NEVER be lent to somebody else or they will ruin it for you.
Invest in a good quality temperature controlled one. I mean a 'proper' temperture controlled one, not a Beijing special with some funny bi-metallic strip half-way down the handle.
A wipe with a damp (not dripping wet) sponge after every few joints will keep it healthy for decades of daily use. NEVER use an abrasive. Always use a good brand flux-core solder.
Keep a different bit for different solder types. I often use acid core solder for working with aluminium but any residue from that would not only ruin my 'everyday' tip but it would also eventually eat through copper tracks on 'regular' PCBs.
As with any tool, look after it well and it will survive a long time.
My wife looks after me well which is how I've survived so long;)
 
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Dippy

Moderator
Does she give you a regular wipe with a damp sponge too?

(I refrained from getting a tip innuendo in there.)

I second and third the purchase of a GOOD quality soldering station. There are three or four good makes out there and none of them are 5 dollar specials from EBay-jing.

Quality costs, and it lasts, and it will give better results and a more pleasant thing to use.
But, of course, this will probably fall in deaf ears and people will still buy the cheap stuff and wonder why it doesn't solder properly or burns the tracks off the board.

I've just tried a medium-to-good rub using Scotchbrite on a well caked tip. Didn't get the nasty stuff off but I've got a very shiny end now. Solders a treat. I shall refrain from doing it 10 times an hour though.
I guess the main thing is frequent cleaning as much as anything and don't leave your iron on unused for hours - oh I think I said that 20 posts ago.
 
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Protolisk

Member
Anyone know where I can find spare tips for the T-1976 from dick smith that isn't from the sydney branch cause mines screwed after using sand paper.
 
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BCJKiwi

Senior Member
See that model has a sponge on top so if you don't have yours anymore, suggest you get some of those from spares at the same time.
 
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Ralpht

New Member
What's your problem with Sydney ?

Any Tricky Dickie store should be able to get it in for you as long as it's still in stock / on their cattledog.
 
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Grant Fleming

Senior Member
Protolisk,

Go to your local Dick Smith store.
Ask if they have the tips you want.
If not, ask them to get them in to the store.
Ask them how long it will take - (should be just a couple of working days).
Ask them to ring you when they arrive (more likely you will have to prompt them).
You do not pay any postage, your store is there to provide you with what you want.

About a year ago I did all of the above for exactly the same soldering iron tips you want. I got one of each size for the T1976 iron.

Cheers,

Grant
 
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