Solder fume extractor filter inserts - Page 1
Forum section: electronics / general

author: tygersmoke
author_rank: Contributor
timestamp: June 03, 2020, 02:29:16 am
content: Hello,After all these years, I plan to start using a solder fume extractor; I currently just hold my breath! I am a recently retired fireman and did the same thing with car fires until we were told wehadto use an airset! Oh well, better late than never, but I am pretty good at holding my breath, haha.....Anyway, being a notorious tight arse, I am planning a diy fume extractor with stuff I already have here. My question is in regards to the filter inserts; are they only the activated carbon foam, or are there additional inserts (requiredoroptional)?Thanks and regards,Phil

author: notsob
author_rank: Frequent Contributor
timestamp: June 03, 2020, 02:41:49 am
content: here's an example of a weller filterhttps://au.rs-online.com/web/p/soldering-fume-extractor-accessories/1411999?ef_id=EAIaIQobChMIkYjKm8_k6QIVgTgrCh07DgaREAQYBSABEgLjDPD_BwE:G:s&s_kwcid=AL!8733!3!437082677234!!!g!314296344196!&cm_mmc=AU-PLA-DS3A-_-google-_-PLA_AU_EN_Hand_Tools_Whoop-_-(AU:Whoop!)+Solder+Fume+Extractor+Nozzles+&+Arms-_-PRODUCT_GROUP&matchtype=&aud-828197004210:pla-314296344196&gclid=EAIaIQobChMIkYjKm8_k6QIVgTgrCh07DgaREAQYBSABEgLjDPD_BwE&gclsrc=aw.ds

author: coppercone2
author_rank: Super Contributor
timestamp: June 03, 2020, 03:11:28 am
content: activated carbon takes care of vapor phase and solid filter takes care of particulate (i.e. condensated dust from smoke), theoretically speaking, however the carbon mesh itself will act as a mechanical filter in addition to a chemical filter..but I am not sure, there is also something called a molecular sieve behavior to think about. but the carbon also does something in terms of chemical reaction more so then a simple molecular sieve. and there are also electrostatic effects (this is how a simple respirator works, i..e standard issue n95).Usually cheap ones are a carbon, expensive ones are a hepa + carbon,you could get a 60$ benchtop air purifier from honeywell that has carbon inserts. works fine for my 3d printer to keep smell awayso when you use flux, you have alcohol, which is a gas, that chemically interacts with the carbon filter, then smoke which is a particulate and vapor and some distribution of particles formed by the smoke will require a filter beyond carbon filter's crude filtering capacity to filter out.so it all turns to gas the solidifies into small particles but the alcohol stays a vapor for a while, or something like that.Also would say if your lab space is small, the bench top air purifier is a good choice because you can also use it to neutralize the smell of commonly used things like epoxy, silicone, cleaning alcohol.. the only problem with them is that they don't have the heavy suction of a solder fume extractor, so some stuff might get out unless you take some measure to channel the smoke.Good idea if you plan on using stronger glues.. after you use it a bunch epoxy can sensitize you. Also of course it keeps down on super glue and cleans the air from a lab printer. And of course you might forget to clean some nasty eBay buy, and have it shoot dust out when you turn it on.this one is a good value IMOhttps://www.honeywellstore.com/store/products/honeywell-portable-hepaclean-tabletop-air-purifier-hht270w.htmIf you want to make a home made one, and only use carbon, you will get rid of the smell but some particles may get through (invisibly small). If you go for hepa, the filters are sized for appliances, so even if you use cheap building materials, I don't think you would save much, especially if you build it nice (say polished wood for the interior so its cleanable).If you build it, you need to be precise, its like a gasket, so you need to make sure the filter sits properly and there is no air flow around it, a common mistake might be to make it too weak so it bends under suction flow and forms a gasket leak. And there is probobly a rule some where that tells you how to use tracer smoke to test it, because the problem is it might capture all the visible heavy particles, but not the invisible lighter ones, so I assume you would have a test where you generate smoke (i.e. dirty fire with rubber) and look at the 'whisp' that it forms while its going into the filter, and gives the visual appearance that the filter is over powered (i.e. the visible smoke only reaches 50%* filter inlet height). A powerful columinated light may allow you to inspect the outlet stream for particles big enough to be detected as reflectors under strong light).*i don't actually have a figure, its just a number i made up to make a point**seals are particularly imporant for a solder fume extractor, because it has a higher suction, its more noisy, so you will only want to use it for soldering, not as a room air purifier, so if that is your only purifier, it needs to capture everything in 1 go, wheras what happens with a room filter is it keeps recirculating air, so you reduce efficiency of the filter, but it can still bring it down to some good level after a while, because statistically all the stuff will hit a filter after enough cycles through the machine. If you just power a extractor on for the duration of soldering, and power it off, anything it does not capture at that point will not reach the filter, and it will stay in the room until it settles or is replaced by fresh air.

author: tygersmoke
author_rank: Contributor
timestamp: June 03, 2020, 04:18:35 am
content: Thanks guys. Another option I have is to simply duct it outside; my workspace has sash windows directly at the back of the bench.cc2, thanks for the detailed response! I have some Christie (commercial) projector filters that have a very n95-ish fibre. Did I read somewhere that material is 'blown' PET? Anyway, they are already gasketed, so it may be as simple as adhering the carbon mat to it and then making suitable enclosure and just chucking them out and replacing when needed....probably outlive me, it's just a hobby station.I like the idea of a laser to check out smoke flow; thanks again!Regards,Phil

author: coppercone2
author_rank: Super Contributor
timestamp: June 03, 2020, 04:24:51 am
content: I don't think the electrostatic ones last very long, they work good for a person because they are very very good for a short amount of time, iirc its like 8 hours of breathing before it looses effectiveness, and a human does not use much oxygen. So I don't think they are a good choice. If you ever take a hepa filter apart you will see its very bulky.It's not that they get clogged, its more like the electrostatic charge is depleted like a capacitor I think. A hepa literally clogs or gets torn apart by aggressive dust I think. Or it gets clogged enough that the fibers start moving apart and making gaps under the vacuum (openings form). So I don't think just putting a massive fan on a HEPA is a good idea to 'make it work clogged'.I hate filters and glue because it feels like a yearly tax but I suppose you need to stay practical and alive. Water, air, vacuum cleaner, furnace filters add up. But you can save some money by vacuuming the filters occasionally to reduce demands on the fan etc, so long you don't get a false sense of security. I think people fail to integrate filter cost into retirement plans and end up having degraded life styles...

author: tygersmoke
author_rank: Contributor
timestamp: June 03, 2020, 04:48:28 am
content: Quote from: coppercone2 on June 03, 2020, 04:24:51 amHaha; nice euphemism! Or is that 'eulogy'?

author: coppercone2
author_rank: Super Contributor
timestamp: June 03, 2020, 05:45:56 am
content: trap for old players*cough* stealing wifes nail polish for potentiometers *cough*a design for a good tested DIY solder fume extractor with actual smoke testing and stuff would be nice to have, so people can actually build something good out of scrap wood (so long they use fuses).. including fan and filter spec. They defiantly can be built because its a simple devicethat is actually a good electronics project, hot wire aneometer, calibration fixture for it, etc.

author: thmjpr
author_rank: Regular Contributor
timestamp: June 04, 2020, 09:33:01 pm
content: Ducting outside is the cheapest and best method, if it is an option.Low cost internal filter:https://www.eevblog.com/forum/reviews/the-best-diy-fume-extractor-for-under-$50/msg2803112/Some recent room based air filters will have particulate matter sensors built in, or they can be bought for ~$100.I wouldn't screw around with filters you already have unless they are HEPA rated or equivalent.https://www.eevblog.com/forum/blog/eevblog-1305-hepa-solder-fume-extractor/

author: coppercone2
author_rank: Super Contributor
timestamp: June 04, 2020, 09:43:53 pm
content: if its all he can afford and still wants to do it its still going to be better then nothing, and HEPA is also not like a guarantee, the high grade hepa filters are expensive too (they come in grades). So its not like you have the best protection as soon as you get a generic hepa filter. They will just reduce your dose in the case of a fume extractor, since it does not recirculate!Venting it outside is the best option by far. And less noisy and power hungry since it has very low impedance, save for a bug screen. All you have to do is worry about the motor bearings. And so long the suction is there, no filter can beat it, unless you are in a really shitty building and you are pulling crap into the work area (this can be a hazard in a factory if you end up getting something worse from a adjacent space), so you might want to think about where you want the fresh air to come from (preferably not from cracks in the wall, or from where its being pushed out). Of course, you are contaminating something else by doing that.https://evacuumstore.com/p-28313-different-grade-hepa-filters-for-vacuums.aspxAnd something to keep in mind is, how to clean ducts. IF you build something you might want to consider building it so it can be cleaned well, because you could expose yourself to a massive dose of crap when you go to clean the duct eventually. Those professional bendy modular hose fume extractor ducts are a complete bastard to clean, and the joints seize up from flux too.

author: tygersmoke
author_rank: Contributor
timestamp: June 04, 2020, 11:27:09 pm
content: Actually, my preference is to duct outside and I could have something up and running today if that were the case. The problem with that is, my 'lab' is my front-most kitchen bench! Although I am flying solo so WAF is not a factor, itdoesneed to be able to be stowed every now and then. All that crusty toxic stuff flaking off when I move it prolly defeats the purpose.I may end up going down the path of a finished product, but I have some nice Papst fans I can use, an articulated stand that I feel I can repurpose, aforementioned commercial projector filters which would be close to, if not actual, HEPA grade. And hey, I certainly have time on my hands, so it will keep me busy for a while nutting it out.....

author: tygersmoke
author_rank: Contributor
timestamp: June 05, 2020, 12:12:40 am
content: Quote from: thmjpr on June 04, 2020, 09:33:01 pmThanks for that; clearly I need to avail myself of the search function! In Australia, those canister HEPA filters are a bit thin on the ground, though I'll have a sniff around and see what's available. I have two large room HEPA filter units here that use 300mm diameter cartridges, but would be total overkill for this project, and anyway I use them in hay fever season.The performance looks terrific. Anything would be better than what I am doing currently though! Great food for thought.Regards,Phil