Rosin-free solder

[starjump]

Hello,

This is my first post, I hope you will forgive (but please point out), any forum blunders.

I found out some years ago at the doctors, that my dermatitis was chiefly due to a sensitivity to colophony / rosin.

Can anyone advise me as to which solder I might try? I wish to try a rosin free type, but if your combined wisdom is against that sort of stuff, then maybe I'll use the rosin version: with precautions.

Many thanks,

[joeyjoejoe]

Just buy a no-clean solder.

[helius]

That's unfortunate, because the alternative fluxes for electronics either smell awful (REL0 types), or require careful cleaning to prevent post-soldering corrosion (OR/water soluble types). If possible, I would use normal rosin solder, but with fume extraction turned on and wear nitrile gloves if needed.

[wraper]

I'd suggest spending money on fume extraction. There are synthetic fluxes without rosin in them but they are just as nasty or even worse. Even If you don't have any health issues, you should not breath flux fumes.

[cdev]

Use a strong self contained fan and some flexible duct to grab the solder exhaust right at its source and channel the air via a fan to the outside.

Don't waste your money on the so called fume extractors that do not actually extract anything in most cases. (because the carbon in their filters is inadequate to the task and rapidly becomes loaded at the molecular level with fumes of all kinds, not just the solder fumes)  So those units basically just are air cleaners cleaning out dust and other particles, not gaseous pollutants.

Exhausting the fume laden air outdoors and replacing that air with clean air is what you should do.

Its easy to buy or make your own dual air exchanging fan. Spend a bit more (they start around $250) to buy one with a heat exchanger.

An HRV combines a dual fan with a heat exchanger between the two air flows. 

That heatsink between the two flows, saves around 65-70% of the energy in the air from wastage in winter and has similar money saving effects in fall and spring, (and even summer by reducing the need for AC, a lot, it seems. )

[GeoffreyF]

Fume extractor as others have said. However, as a beginner you can do a very great deal with breadboards such as this: https://www.adafruit.com/product/64

They come in a variety of different sizes of course.  You can connect up some pretty complex circuits with that.   Worst case, once you have it working, you can ask a friend to solder it all to circuit board. 

Just a thought.

[starjump]

Thank you all for your responses.

I understand that rosin flux would be best. Shame I'm not good with the stuff.

Rosin /colophony is a pine derivative and used in industry in all manner of things from floor polish to printer ink. I can pick up a magazine without worries, but I react with it if it is in it's stronger more concentrated form, ie pine wood sawdust that touches my skin (or enters my airway or eyes).

I will probably have to go with it with precautions but are there any decent alternatives that might work for me please?

Many thanks.

[helius]

https://amtechdirect.com/product/amtech-solder-flux-lf-4300-tf/
REL0 (Resin-based, low activity, halide-free) which after activation can be left uncleaned, or washed in hot water.
available in Sn63Pb37 and Sn96Ag3Cu0.5 solder wire and as flux paste

Kester 979 or 952
ORL0 (Organic acid based, low activity, halide-free) which after activation can be left uncleaned, or washed in hot water.
Available as liquid in bottles or pens

[starjump]

Thank you Helius for your quick and helpful reply.

I have found some 'AMTECH 4300 Sn63/Pb37 Water-washable Solder Wire 2.2% Resin Core (0.020") 1lb' on ebay.

Would a flux paste be needed as well?

[wraper]

I have found some 'AMTECH 4300 Sn63/Pb37 Water-washable Solder Wire 2.2% Resin Core (0.020") 1lb' on ebay.

Would not recommend that without washing your boards in ultrasonic bath.

[cdev]

I don't know of any (besides the air dilution technique mentioned earlier) but you should keep up on the colophonium reaction issue and atopy in general.

Trust your body's signals. Your body's reactions to things like that can become very non-linear if you get exposed to them too much. Like the proverbial straw that broke the camels back.

But also, sometimes (often) whats put forward as a solution or replacement has its issues too, sometimes they are worse.

Fresh air is better than filtered air. I would also watch out for dermal exposure.

There is a lot of stuff on pubmed about it. Just search on colophony.

Breadboarding makes lots of sense for somebody in your situation, IMHO.

You probably can trust the medical research on this issue, but if I were you if you find a solder that works for you I would try to keep lots of it around in all sizes so you will always have it and not be tempted to use anything else that could make you sick. Look into using a fan that exhausts the fumes outdoors and replaces the exhausted air with fresh.

Thank you all for your responses.

I understand that rosin flux would be best. Shame I'm not good with the stuff.

Rosin /colophony is a pine derivative and used in industry in all manner of things from floor polish to printer ink.

I can pick up a magazine without worries, but I react with it if it is in it's stronger more concentrated form, ie pine wood sawdust that touches my skin (or enters my airway or eyes).

I will probably have to go with it with precautions but are there any decent alternatives that might work for me please?

Many thanks.

[mariush]

Buy some nitrile gloves,they're thin enough that you'd still be able to use all the tools and rosin vapors / flux smoke / whatever doesn't get absorbed by your skin.  Here's an example: https://amzn.to/2IRE7ix

Use some fan to push air away from you.  Ideally use a air filter with activated charcoal, but simply having a fan blow the solder smoke away from you would help.

I'd say use no-clean solders, read the MSDS (material safety sheet) and see what the main chemicals inside the flux are, pick one with less amount of rosin. Avoid water soluble fluxes, as you'd have to really clean the boards after soldering and it's difficult to clean properly.

[wraper]

Buy some nitrile gloves

They suck. Your hands will sweat very fast, not comfortable at all. I would suggest ESD gloves with rubberized fingers or rubberized inner area. TME sells cheap ESD gloves which are quite comfortable, even for prolonged use.

https://www.tme.eu/en/details/glove-esd-rs2_m/esd-clothing/
https://www.tme.eu/en/details/glove-esd-rs3_m/esd-clothing/

Just avoid these: https://www.tme.eu/en/details/glove-esd_l/esd-clothing/   they are junk

[Ian.M]

Some tasks are much more difficult to do wearing any sort of gloves.  Even handling PCBs a lot, residual flux on them may be an issue for you, (e.g. I am sensitive to the factory flux used on Ferguson TV boards in the 1980s), and a good barrier cream helps.  Try to avoid manual washing of flux from boards, and if you must, wear heavy solvent resistant rubber gauntlets for that operation.

There is no substitute for good ventilation, and actual fume extraction so the fume concentration does not build up in your work area. 

Wear a lab coat to keep rosin residue off your clothes, and when it's significantly soiled, have it dry cleaned or take it to a launderette so you don't contaminate your washing machine with rosin, or at the very least, if you wash it in your own machine, afterwards run a full length wash cycle with the machine empty at max temperature and with detergent before using it to wash any fabrics that may be in sustained skin contact.

[cdev]

If I were you I would mark the outside of the gloves clearly when you put them on, and ideally, even if you only use them for a few minutes,  don't reuse them- because you might put them back on inside out.

It helps if you don't use your cell phone while you are using them, turn it off.

Activated charcoal filters are for the most part useless for removing chemicals from air in the amounts they are supplied in the fume blowers sold for hobbyist use.

An air filter removes dust, not volatiles. You would likely do just as well with any fan to move the air away from your work area.

An effective activated charcoal filter would have to use a great deal of charcoal so that would mean stronger motor to pull the air through the heavy and likely expensive filter canisters.

[wraper]

Decent fume extraction(filter) system will cost 400EUR+. If there is possibility, the best would be to remove air to the outside instead of filtering it.

[starjump]

Hello and thank you for all of your kind responses.

I have, over the years done as many of you suggest and used nitrile gloves in other manual work, woodwork, vehicle maintenance etc. It is a good point. The quality of the glove does vary, you find your favourites, as people have pointed out. I found the latex ones un-useable personally, as I reacted to them. Hairdressers with skin conditions told me the same thing.

Avoiding the allergen does seem to make a big difference, obviously. I have scraps of oak and other hardwood in my shed, but pine is banned!

Thank you again for your concern. I will have to experiment a bit, wrapping myself up like an Egyptian Mummy and forcing fumes outside in some way.

The number of different solders is bewildering. 

[starjump]

I will also try the ESD gloves mentioned, thank you 'wrapper'.

[Ian.M]

You can set up effective fume extraction fairly cheaply.  Get a small inline bathroom duct fan + matching ducting.   Use full diameter ducting for as much of the run as possible.  For the outlet, if possible  have a dedicated one, otherwise make up an adapter board with a fitting for the duct on it, edged with foam draft excluder strip to fit in a partially open window, or to fit over an exterior air vent.  Running costs will be a few pence per hour for electricity + the extra load on your heating system to warm up the replacement air.

N.B.  such a system may *NOT* be safe for extracting fumes of flammable  volatiles at significant concentration or flammable dust, so don't use it for solvent fume  extraction. If you need to extract potentially explosive vapours or dusts, you need an intrinsically ignition-safe fan and conductive or static dissipative ducts, or at least a bare grounding wire run through the ducts to minimise static buildup.   If you cant find an affordable ignition-safe mains duct fan, suitable 12V fans can be bought from marine chandlers, sold for bilge ventilation applications of petrol engined vessels.

[GreyWoolfe]

I have, over the years done as many of you suggest and used nitrile gloves in other manual work, woodwork, vehicle maintenance etc. It is a good point. The quality of the glove does vary, you find your favourites, as people have pointed out. I found the latex ones un-useable personally, as I reacted to them. Hairdressers with skin conditions told me the same thing.

I don't know if they are available across the pond but I use Grease Monkey brand nitrile gloves.  They are latex free.  Yes, they do make my hands sweat a bit but they are comfortable enough to use.  I get them from the local home improvement store.  I prefer that to the inevitable flux that ends up on my fingers and washing them with IPA to get them clean.

[KL27x]

They suck. Your hands will sweat very fast, not comfortable at all. I would suggest ESD gloves with rubberized fingers or rubberized inner area. TME sells cheap ESD gloves which are quite comfortable, even for prolonged use.

Finger cots are useful where you have to handle small items. For soldering, you probably need to take some care with the side of your hands, too, to avoid setting your hands down on splatter or excess liquid flux that gets on the bench.

[starjump]

Thank you for all of the posts. I will report back on how I get on. In the meantime, I am going to try this solder:

https://www.rapidonline.com/warton-metals-omega-63-37-fast-flow-2-flux-solder-wire-22swg-0-711mm-500g-85-6154
https://www.ebay.co.uk/itm/22SWG-500g-ROSIN-FREE-SOLDER/263701622136?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

I have ordered some today from eBay.