Solder fume extraction - what's the best option? - Page 1
Forum section: electronics / general

author: SolderSucker
author_rank: Regular Contributor
timestamp: September 09, 2017, 09:44:31 pm
content: I've been soldering at home for the past 20 years but not for long periods, sometimes not at all for days on end, but then I can end up soldering maybe for an hour (in total) or so for a few days. I've had very mild asthma for many years but I'm sure that the solder fumes aren't helping matters, particularly as my asthma has become a little worse after some intense soldering over the past few days. I know it's the rosin flux which causes the throat and lung irritation and I've just ordered myself some solder which doesn't use a rosin-based flux. That will help but doesn't get around the issue of desoldering old solder from old PCBs.I've now set up a basic fume extractor (with filter) on one side of my workbench and a small fan on the other to blow the fumes towards the extractor. It's a temporary measure until I find something better. This is the fume extractor:https://www.reichelt.com/de/en/Fume-Extraction/FILTER-426-DLX/3/index.html?ACTION=3&GROUPID=4135&ARTICLE=87379Nwo I know that units such as this:http://uk.farnell.com/weller/ft91006699/fume-extraction-kit-1-funnel-230v/dp/2478431are expensive, but I feel it's worth it for the sake of my lungs.Weller make a lot of floor standing extraction units but I can't decide on which one to buy.I'm also undecided regarding the best way to extract the fumes - either the type with a thick desk-mounted hose or the type that attaches a thin metal tube to the soldering iron, the only problem with this approach is that I also have a Denon SC7000Z desoldering gun and I can't think how how would attach such a device to that. It's looking like the best "all encompassing" approach is a floor-standing unit with a thick desk-mounted hose.Can anyone offer any advice please? Thanks.

author: cdev
author_rank: Super Contributor
timestamp: September 09, 2017, 09:51:34 pm
content: The best way is to have two fans, one exhausts the fumes out a window from right behind your work, and the other one pulls in an equal amount of fresh air from outdoors at the same time. The two vents, the intake and the exhaust should be pointed in different directions so the fumes don't get sucked back in again.No filters are needed at all.Also, its possible n-acetylcysteine (NAC) might help you.. (well actually, all of us!)https://www.ncbi.nlm.nih.gov/pubmed/?term=asthma+acetylcysteine

author: Ian.M
author_rank: Super Contributor
timestamp: September 09, 2017, 10:15:10 pm
content: The best and cheapest option is to extract the fumes and vent them outside. Laboratory fume cupboards don't vent to the room, nor should your fume extraction system. Yes it costs more to run than you would initially expect because you have to heat or chill the replacement air that's drawn in from the building's vents, but on the other hand it doesn't have expensive filters that need regular replacement and it doesn't let toxins build up. You do have to make sure your vent isn't going to cause a nuisance - if you are doing it commercially on a large scale you'll probably need an electrostatic precipitator and filters to comply with local environmental regs.For a cheap DIY hoze to bench top solution, you'll need an inline duct fan, preferably one that can be speed controlled and enough ducting to get to the vent - either a dedicated one or an adapter plate onto an existing window or vent. The last meter of hose can be adapted down to vacuum cleaner hose for a more manageable size on your bench. Position the nozzle behind and above your work Adjust the fan speed to get enough suction to pull the fumes in without excessive noise or cooling of the work.If you've got a compressed air supply you can use a vacuum ejector and small bore vacuum hose between it and a suction probe clipped to your iron. Again, vent it outside - don't attempt to filter the crap out and recirculate the air. You'll probably want a trap packed with wire wool between the probe and the injector to stop any large particulates reaching the ejector.The Denon looks fairly easy to mount a pickup tube to. Simply replace the nuts on the top two case screws with threaded hexagonal spacers, so you've got enough thread to put a short screw into, then use those mounting points for P clips to hold a copper pickup tube along the side of the gun with an angled end bent to position it where you want it.

author: cdev
author_rank: Super Contributor
timestamp: September 24, 2017, 04:19:46 am
content: If you can afford a heat recovery ventilator, they really are by far the best solution. Whenever you run an exhaust fan, for example, a bath room fan, it needs make up air - which unless you have windows open, is pulled through cracks in your wall into your house.So that air is dirty unless you have remembered to open a window wide which may be very cold in the winter..The next step up is a dual window fan that both pulls air in and exhausts air at the same time.If you have a mild climate that may be all you need. I have not seen these sold but what would be ideal is two quiet, high volume fans with a hose on one of them for use at the workbench to gather the fumes, mounted in a frame that can be fitted permanently into a window or removed when its not being used.. The next step up from this is an HRV, either a small one for your your work room or a larger one for your whole house/office. With an HRV you want to site the returns (exhaust to outside) behind and above your work bench.An HRV has a "core" that exchanges heat. Its basically a large square heat sink with two air paths through it perpendicular to one another. It has filters on it that last forever. However they and the core need to be cleaned of dust and washed off with slightly soapy water every few months. Thats it.They are built to run all the time and they are very quiet.