Regularly Using Flux Paste to Clean Iron – Good Idea? - Page 1
Forum section: electronics / beginners

author: techie1234
author_rank: Regular Contributor
timestamp: August 13, 2016, 03:34:24 pm
content: I have been trying different ideas to improve my soldering results. To that end, I’ve been using a rosin flux paste more often and one of the things I’ve been doing is applying some flux paste to the tip every 10 minutes or so to really get the tip clean and then retinning it. At first the results were excellent, but now it seems that the results are waning a bit. I think I might see a bit of the copper on the tip when it’s really wiped clean. So, I’m starting to wonder if I’m doing more harm than good fluxing it all the time. Or, perhaps, it's just coincidence. Thoughts?The iron is a Weller WP35 and the flux is SRA Rosin Paste Flux #135.

author: Ian.M
author_rank: Super Contributor
timestamp: August 13, 2016, 03:46:42 pm
content: From SRA's website:Quote#135 is a RA rosin/petroleum jelly flux. So you've been using an aggressive flux frequently without cleaning the residue. I'm not surprised you are seeing excessive tip wear. Also I hope you have excellent fume extraction!Seehttps://www.adafruit.com/datasheets/hakkotips.pdffor proper tip care.

author: techie1234
author_rank: Regular Contributor
timestamp: August 13, 2016, 04:00:07 pm
content: Quote from: Ian.M on August 13, 2016, 03:46:42 pmAlthough I had looked at the SRA web site, I must have missed that the #135 was activated - so what I experienced certainly now makes sense (both getting the iron super-clean but with some real wear on the tip). If I used an R or RMA flux, would this change whether the idea is a good one? I've seen some people say their soldering technique involves fluxing their iron between each individual joint.On a related question, I have found that I like the paste flux for certain things better than the liquid / pen - does anyone have recommendations on a R or RMA flux paste?

author: Ian.M
author_rank: Super Contributor
timestamp: August 13, 2016, 04:28:30 pm
content: A block of pure pale rosin to flux the tip with when re-tinning will do no harm as long as you don't let its residue build up and the tip temperature is well controlled. However unactivated rosin does nothing whatsoever for a de-wetting problem and can make the situation worse, so you also need something more aggressive e.g. a block of Ammonium Chloride/Tin powder tip cleaner that you use as infrequently as possible.

author: helius
author_rank: Super Contributor
timestamp: August 13, 2016, 04:48:08 pm
content: Get yourself a brass tip cleaning pad like the Hakko 599 or Plato CS50. They are coated with rosin flux to better clean oxidation off the tips. They work very well; in most cases you won't need a wet sponge at all (if you do use a sponge, use distilled water only. salts and chlorine in tap water could be causing the corrosion you're seeing).Quote from: techie1234 on August 13, 2016, 04:00:07 pmKester SP-44 is an excellent paste flux.

author: Ian.M
author_rank: Super Contributor
timestamp: August 13, 2016, 05:02:14 pm
content: Its not so much the minerals in tapwater that's the problem, its the buildup of burnt flux residue, metal oxides and the concentration by evaporation of the minerals from the water in the sponge. You need to wash the sponge out thoroughly daily to minimise the buildup, and yes, if your water is particularly mineralised or heavily chlorinated, then squeezing it out as dry as possible with a wad of kitchen towel then rewetting with distilled/deionised water can help. If the sponge surface is charred, that needs scraping off with the sponge bone dry to get down to un-burnt sponge. Change it when it gets too worn.