Fear of Flux - Page 1
Forum section: electronics / projects

author: martys
author_rank: Regular Contributor
timestamp: December 24, 2017, 06:26:47 pm
content: Soldering Sages, pray tell, what Pb/Sn solder wire and liquid flux works best and is least toxic?I am been soldering for 50+ years, and hand soldering SMD circuit boards seems to have damaged my eye and lung health.I've noticed in recent years my eyes would blur after several hour sessions of soldering without using any eye protection. After a good nights sleep my eyes would seemingly returned to normal?.. or did something more damaging remain unnoticed?Then recently, a yearly checkup showed my lung function was below normal, I had cataracts and glaucoma, even though I don't smoke or live in a smoggy city.I have had cataract surgery which fixed the cataracts and glaucoma, and my lung health has improved greatly as shown by a lung function test, since I have stopped soldering so much while at the same time, exercising more.I love my electronics hobby and soon need to buy my next pound of solder wire.I have not been soldering much lately. Now I must wear glasses to see what I am soldering. Perhaps that is more benefit than handicap.I'm scared.Now, I have flux phobia!My most recent pound of solder wire wasMulticore Crystal 400. I also use MG Chemicals "No Clean" flux.

author: Gyro
author_rank: Super Contributor
timestamp: December 24, 2017, 07:05:57 pm
content: Sorry to say it, but it sounds more like the symptoms of getting old(er) to me!

author: Kleinstein
author_rank: Super Contributor
timestamp: December 24, 2017, 07:09:19 pm
content: It is kind of normal that eye sight gets worse with age. That has nothing to do with soldering - maybe a little with too much staring at a computer at fixed distance. It is kind of normal that at an age of about 50 the eye can not change the focus very much and one will need gasses for close up of far out viewing. One ht other extreme young children con compensate a lot by adjusting the focus over a wide range. So far the some can even see sharp under water without glasses. Similar the cataract is more problem of UV exposure over time.The decomposition products of flux can contain some relatively nasty stuff, at little like what one finds in the smoke of cigarettes. Some people are more sensitive to those and might even react with a kind of asthma. So good ventilation of a smoke filter is a good idea. However there are other sources of air pollution and pure health. A not so healthy lung might react more sensitive to the smoke, but this does not mean the soldering was the reason that caused lund damage.In the US there is another more psychological problem: things get very dangerous once you find out or get proof they are dangerous, but nobody cares before there is a reasonable proof. So things are either very bad or not a problem at all. In the US they somehow forgot the category in between - no healthy but it won't kill you.

author: nanofrog
author_rank: Super Contributor
timestamp: December 24, 2017, 09:07:23 pm
content: I'm withGyroon this one, as I'm going through it with vision due to being in front of a computer monitor.These days I wear glasses, and have purchased a microscope for working with SMD. And regardless of lung health, proper ventilation is always a good idea. Good solutions aren't always expensive either (I've ~ 20 y/o a HEPA unit that's still going strong).In regard to fluxes, the synthetic versions tend to be a lot nastier health wise than the rosin based stuff. Personally, Kester 44 (RA) in 63/37 is my go-to as it's good for both new as well as rather old/heavily oxidized stuff.

author: martys
author_rank: Regular Contributor
timestamp: December 24, 2017, 10:06:42 pm
content: My questions remains, if you've tried several for use in printed circuit SMD PCB reflow assembly:What do you solderers think makes the best Pb type solder wire to use?What do you think makes the best liquid flux to use to apply packaged in a syringe?

author: Audioguru
author_rank: Super Contributor
timestamp: December 24, 2017, 11:16:08 pm
content: I got older then got reading glasses.I got much older then got cataracts so with the new lenses in my eyes I don't need the glasses anymore.Then I got a heart attack but I survived when they fixed two blocked heart arteries.Then I got hearing aids and new teeth.Now I am young again.

author: slugrustle
author_rank: Frequent Contributor
timestamp: December 24, 2017, 11:25:32 pm
content: Hi martys,I have a sensitivity to rosin flux fumes; even small exposure exacerbates my asthma. I wear a respirator at work with 3M 60923 filters (P100/Organic Vapor/Acid Gas). I just bought some 2091 filters (P100 only) to see if it's just the particulates that need to be filtered. I know there are fume extraction systems that use HEPA filters, and these are recommended by the British guidelines on the topic (link below) as a second best option if you can't vent your extraction system to the outside.http://www.hse.gov.uk/pubns/guidance/SR20.pdfFor soldering at home, I use solid core Tin-Bismuth solder (fromhttps://www.solderstoreonline.com/) with Superior #30 liquid flux. I still wear the respirator with acid gas filter when using this flux as it can give off small amounts of HCl when overheated, but at least there won't be rosin fumes in the room when I'm done. The flux contains halides (it is glutamic acid hydrochloride), which are conductive, so I wash my boards with distilled water heated to 140 fahrenheit after I'm done soldering. I sometimes add a few drops of Triton X100 surfactant to help speed the drying process (hair dryer). This process works well for me, although I wish the Tin-Bismuth solder came in thinner wire gauges and that the little balls of hot solder didn't stick to soldermask.

author: zdelarosa00
author_rank: Regular Contributor
timestamp: December 24, 2017, 11:46:27 pm
content: Okay, comments out of the way... Get two things done:1.-Get a decent fume extractor2.-Get a heavy-fume mask (I use one when soldering)Extras: Try the lead-less solder, as regards to flux, a common flux pen (since you do smd) seems fine by me, but i dont know if lead-less solder can come in flux-core versions (I use lead).Also, old flux, too high temperature on the iron or bad quality solder REALLY gets fumey and smokey.Another suggestions:a.-Well ventilated room.b.-If you do 90%+ of smd, you should really consider an oven or a hot air gun now.

author: zdelarosa00
author_rank: Regular Contributor
timestamp: December 24, 2017, 11:51:34 pm
content: New suggestion:c.-Don't go easy with eye protection, its a must.d.-Well-iluminated work stations are a blessing, mostly if they're LED since it's more directional, powerful and it's generally colder toned light (warm tones help at feeling tired).e.-Again, your sight should not be a lousy consideration, don't force it and get a microscope or at least a desk magnifying glass (those from watch repair with a ring fluorescent light).

author: martys
author_rank: Regular Contributor
timestamp: December 25, 2017, 12:31:22 am
content: blueskull: What is a "pair off iron"?Isn't using a heat gun a good ware to quickly spread flux fumes throughout the room?The real problem is in winter, means I have to make a choice between a comfortable workplace with some diffuse, occult solder fumes or a healthy but very cold drafty room that makes my life miserable. In summer I can work on my projects with the windows wide open.I noticed that some solder formulations have fluxes which emit what seems to be toxic chlorine or other strong chemical fumes and I have banished them from my workbench.To attempt to lower my exposure to toxic fumes, I have so far installed a 4-in fan that I turn on when I want a breeze pushing fumes away from my face, I now use a circular light-magnifier glass to peer through and also my glasses deflect some of the fumes.But what do you all think is the best solder? Is my "Multicore Crystal 400" formulation a best choice? Is rosin-core less likely a hazard?Maybe time to bring on the charcoal and HEPA filters! I am not ready to dress up like I am working in a clean room.I can't help but think that the accumulated effect of months and years of exposure to mild, but toxic substances slowly leads to major health issues, like eye problems, lung problems, heart trouble, GNW, even cancer.I am completely sure age is going to getcha, but you can always accelerate that process.

author: nanofrog
author_rank: Super Contributor
timestamp: December 25, 2017, 06:21:23 am
content: Quote from: martys on December 24, 2017, 10:06:42 pmFor a syringe (i.e. paste/gel/tacky flux), I prefer Kester RF741. Amstech is good as well, but is also highly counterfeited.For liquid, I use 186 (RMA, which is the equivalent to what's in Kester 285) or 1544 (RA equivalent to what's in Kester 44 solder wire). 1544 is my primary, and I buy it in small bottles as the disposable pens are expensive for the volume you get.I chose to use a refillable brush pen as it allows a lot of control IME. YMMV, and there are other inexpensive methods; really comes down to personal preference.

author: David Hess
author_rank: Super Contributor
timestamp: December 25, 2017, 01:54:41 pm
content: The list of things which when vaporized are good for your lungs is very short with air and water vapor pretty much filling it. The body should handle rosin and other natural organic fluxes better than synthetic ones. As far as rosin itself, there is that persistent link between exposure to pine trees and sarcoidosis. If I was doing production work or operating my soldering iron continuously, then I would invest in a fume extractor.My favorite general purpose flux is fully activated rosin like Kester 44 but when working with new boards and parts which have not had time to tarnish, less of a a less active flux may be used reducing fumes.

author: GreyWoolfe
author_rank: Unknown
timestamp: December 25, 2017, 04:15:18 pm
content: I use Kester 44 63/37 solder and MG Chemicals 835 RMA flux in a small squeeze bottle that has a syringe on it. I also use a Weller fume extractor, a headset magnifier and 10,000 lumens of LED light on my workbench. Good soldering equipment that melts solder/heats the joint fast is also a help.

author: rrinker
author_rank: Super Contributor
timestamp: December 26, 2017, 09:42:08 pm
content: Are you nearsighted? I have extremely nearsighted (don't remember the uncorrected number - but I can;t clearly see even the LARGEST letter on the eye chart without my glasses). As such, I am highly prone to glaucoma. I started having a similar blurry vision issue, which I initially put down to the fact that I was working a lot of long hours which usually involves staring at a computer screen. I REALLY noticed it when I visited my best friend and we went to his range to do some shooting - I was HORRIBLE - I mean, I'm no match level shooter, but was was always at least halfway decent, but I was having much more trouble than could be attributed to not having done any shooting for a while and unfamiliar guns. I could see either the sights OR the target but not both at the same time, there were blurry spots in my field of vision. So I set up an appointment when I got back home, the optometrist didn't even say a word after doing the glaucoma pressure check, she just left the room and consulted with the practice's glaucoma specialists. Seems the IOP of my right eye was over 70. The left was 45. I have since had surgery on both eyes to implant small shunts to relieve the pressure and after a year and a half and nearly every medication available, it's finally under control, but I have about half of the field of view of my right eye permanently damaged due the the high pressure damaging my optic nerve. I cannot for example close my left eye and actually type a message here at least without doing all sorts of crazy head movements to read the screen. The left was saved and there is no evidence of damage. However, with these shunts implanted, I now have a pretty much 100% chance of cataracts in both eyes, so I have that to look forward to.Nothing to do with 40 some years of soldering (I never did it for long periods at a time, such as working a full day doing nothing but soldering, just genetics and getting old. Despite obesity, I've been fairly healthy most of my life, but this really scared me because EVERYTHING I love to do relies on vision - electronics, reading, model railroading, driving etc. Not to mention my job. I have cut back on driving at night because a side effect of the shunts seems to have increased the halos around light sources - I am fine on a road with no oncoming cars but oncoming headlights get very annoying and I have a hard time seeing my side of the road until they pass. So as much as I can avoid it, I don;t drive after dark - although this time of year it is impossible as it is dark long before the work day ends.As for flux, it has been only in the past 10 years or so that I've even bothered to use an external flux, and for that I use a stuff called SuperSafe #30, which is water soluble. I still use leaded solder. I don't eat it, or lick my fingers after handling it.

author: nanofrog
author_rank: Super Contributor
timestamp: December 26, 2017, 11:44:49 pm
content: Quote from: GreyWoolfe on December 25, 2017, 04:15:18 pmYou might want to give Kester 1544 a go and see if you like it better than the MG Chemicals 835.I suspect you've seen the link before, but here it is again for convenience; 2 fl. oz. ofKester 1544in a needle dispensing bottle from CML Supply.They offer other types too, includingKester 186. And of courseEP256 solder paste(63/37), andRF741paste flux (same stuff in EP256). All of this is good stuff IME, and CML Supply is wonderful for breaking this stuff down to hobbyist friendly sizes (I know, I sound like a shill; but these products really are that good).Skycraft also sells it (where my current 1544 supply came from back in 2014), so you might want to give that a go instead next time you're in the Orlando area. Not sure it's a regularly stocked item though, so a phone call would save you some time and money if they're out.Oh, and despite it's age, it still works properly. As does the 186 I got from eBay before that.