Lead Free Stained Glass Solder Problem

I have a Weller 80 soldering iron. I have been working with it on several stained glass projects, with lead 60/40 solder and standard soldering flux and having no problems.

About a month ago, I switched to lead-free solder, and continued with various projects and all was well.
Last week though, I found the lead-free solder was no longer working with the soldering iron.

The soldering iron is having difficulty melting the stained glass solder, and when it does, it doesn’t stick to the tip, but rather breaks apart in little balls. I read up on cleaning the tip, which I did by wiping with a sponge. That didn’t do anything. I next tried scraping the tip with steel wool. That too did not work.

Yesterday, I bought a new tip for the 80W iron. I was told that since I was working with lead-free solder, I did not need to tin it. It was already coated with lead, and so, should work right out of the package.

So, I swapped it out with the one that wasn’t working, and it worked great for about 1/2 hour. Then, the same thing started up, with the tip only working on it’s edges. Deductive reasoning told me that maybe it was the flux I was using, or maybe it had something to do with the mix of lead-free solder and the lead-coated tip.

In any case, I’m at a loss as to what to do, and all my stained glass projects have come to a stand-still.

Your help would be greatly appreciated. Jan

Milly’s answer: Great question Jan. This is a tricky one, weighing up the associated health risks of inhaling lead with the undisputed fact that soldering is more difficult – no, really annoying! – with lead-free solder.

The potential difficulties (some you’ve already experienced) are:

  1. Poor solderability – the lack of lead decreases the ‘flowability’ of solder.
  2. Higher melting point – lead-free solder melts about 20 to 45 degrees C higher than 60/40 solder. This results in a shorter life for your soldering iron tip.

Some ideas for optimising your chances of success:

  • Make sure you have the correct size tip for your iron (did you replace like with like in terms of size and shape?)
  • Your flux and tip cleaner should be labelled ‘lead free’
  • Buy flux that is able to withstand higher temperatures and longer dwell times – flux charring, or ‘black tip syndrome’ (sounds bad!!!) can result, meaning that the tip turns black and re-tinning becomes nearly impossible.
  • Clean and tin tip more frequently – keep your iron clean and fully coated (tinned) with solder, as oxidation can occur at higher temperatures.
  • And finally, I’m wondering if your 80W soldering iron is hot enough for lead-free solder? I’ve always used at least 100W for stained glass solder.

I hope that helps, and that you’ll soon be able to resume your stained glass art work – it’s awful when you can’t get on!

Lead Free Stained Glass Solder Problem

Lead free
by: Dennis

The best lead free solder comes from a plumbing supply. The brand is Worthington Premium Select. It’s melting temp is 419°f. Use Nokorode flux. Last but not least and the most important part is use a Hakko 601 soldering iron.

I haven’t found the copper patina that gives me a even effect. Novacon doesn’t work consistently.

Milly says:
Thanks for your advice Dennis, much appreciated and very helpful for everyone.

More lead free solder issues
by: Michael B

I also switched to lead free solder in the middle of a project – not recommended. I find that the copper patina does not work as well as with the lead solder. Just wondering if anyone else has had this happen and what else should I know about using lead free solder.

Milly’s reply:

Work slowly as the lead free solder likes to be hot. It takes practice to get a nice bead.

It can be a bit dull after polishing but patina is tricky too! Your best bet is patina designed for silver. Look to jewellers for supplies.

Iron Tip
by: Anonymous

Most people currently use plated tips, in which case you don’t actually want to file down the tip because it will damage the plating. Now if you use a copper tip, file away.

lead free solder
by: tyee

Clean the tip filing it a little bit. Get some Sal Ammoniac(block) Put a small chuck of stained glass solder on it, and melt the solder and push the soldering iron in to the Sal ammoniac block. This will clean the tip and tinning the iron at the same time. You will need to do this often to keep the tip clean. Yes you must retin the tip on a regular basis by filing and tinning.

Milly’s reply: Thanks for this Tyee. I’m interested that you’d recommend filing the tip – I’ve always thought filing would damage it. I find the tip tinners do the cleaning and tinning work well enough on their own.

18 thoughts on “Lead Free Stained Glass Solder Problem”

  1. Try a trick from electronics world, obtain a curly s/steel pan scrubber( the type that looks like turning shavings) take a small tin ex bean or similar about 1.5ins deep. loosely scrunch the pan scrubber put it in the tin. Dip the soldering iron bit into the sctubber before each run,move it around until bright, get on with soldering, always clean tip before switching off
    Do not file an iron tipped bit , if it gets that bad, buy a new bit. Higher wattage irons will be needed to work with lead free solder.
    I learnt to solder anything to anything as an appentice repair silversmith and have applied that knowledge to various work over the years.

  2. I’m new to stain glass. I want to use as non toxic materials as possible. I bought lead free solder and a non toxic flux . My iron I have up to highest temp and tried seeing if it worked well. I took pice a paper to see if it burned through, it did. My iron tip doesn’t hold a ball of solder. Is my tip bad ? Do I need a special tip when using lead free solder? Any info on the solder tool what’s the best kind and lead free solder etc. would greatly appreciate any info ty!

    • An iron tip would always burn a bit of paper Ing, so it’s hard to compare that to solder. You don’t need a special tip for lead free.

      I’m wondering if your soldering iron is powerful enough. If it’s one that’s a dedicated stained glass iron, then I’ll assume it is. If not, check the wattage to make sure it reaches a high enough temperature to melt solder. 360C minimum.

      The tip may need cleaning. Keep it clean as you go by wiping it on a damp sponge and keep adding flux too.

  3. HI! I am working on stained glass using lead-free lead and I also use Hakko! From some point on, when soldering is performed, the lead cools and turns white. Not only is it not glossy, but it also turns black when applied with a polish. I really dont know why and my all works has been stopped. Can you help me?

    • It is a bit difficult Alice. Use lots of flux, a warmer iron and solder as quickly as you can. Remove flux as soon as you can afterwards.

  4. Hi, I’ve been making little stained glass airplant holders with regular 60/40. I’ve been wondering, if I wanted to make more of a planter, where soil would be placed into it, would I need to use lead free or aquasafe solder? Considering plants would need to be watered and there would be moisture on the pieces regularly?

    • I’ve never been asked or thought about that before Emily! Interesting thought. I guess now I have been asked that it would seem kind to use lead free 🙂

    • Hi Jessica, it’s an interesting question! There isn’t a lead free lead came. You can use zinc of course but it doesn’t bend at all easily.
      Sorry I don’t have a magic solution 🙁

  5. I make stained glass jewelry using lead-free silver solder. I have a hakko fx-601 soldering iron that I use. I use studio pro flux and studio pro lead-free solder. I recently ordered a new brand of copper tape (can’t remember the brand name now!) because I’ve been having issues with the copper tape slightly peeling up once the solder is applied. It ever so slightly curls away from the glass around the edges. I was hoping with a new brand of tape this problem would go away, but I am still having this issue. Has anyone else experienced this? I wrap the pieces quite well, using a fid. I inspect each piece to make sure the tape is flush before applying the flux and then the solder. I would be SO grateful for any insight on how to fix this problem! If anyone has other brand suggestions for solder and flux, I would appreciate that as well!

  6. Just getting into stained glass, I do not wish to work with lead for obvious reasons. Does anyone have recommendations on patina for lead free projects??

    • If you want to patina lead-free solder, you will need a patina for silver. Midas Black Max is one brand. The patina you use for 60/40 or 50/50 solder does not work, because it is formulated to work on tin and lead. Your supplier should be able to order it, or you can look at jewellery making companies like Rio Grande.

      Whether or not you use patina, be sure to finish up with a finishing compound or wax to prevent oxidation and keep your solder looking its best. I hope that helps Destiny.

  7. Thanks for all this excellent information! I am getting back into stained glass work after decades and am working with my son who I don’t want exposed to lead. I am making panels for a snake vivarium as well and don’t want to expose our python to lead. I bought the items Dennis recommended and am just curious as to what tip to use on the Hakko iron – 601 comes with a thick wide tip that has an angled slice that looks like a good match for stained glass work but I also ordered tip T19-D5/P. Is it better to use the 3/16” angled tip or a pointed one? More surface area with a hot iron and hard to melt solder makes good sense to me.

    Thanks all!


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