Looking for Ideas for Venting Smoke when smelting lead outdoors.

[TheCaptain]

Hi,

I have been renting my shop area for many years now, and the smoke and odor of smelting range lead and wheel weights is presently no problem due to where I am situated. My landlord died a few years ago, and plans are underway presently to sell the property which is comprised of a few buildings (on of which is my shop). Eventually, I will have to leave. I am not sure when. I have another area that I can go to, but it is in a residential area - thus neighboring houses. I may be able to find another place like I have now, but in case not, I am thinking of ways to reduce the smoke. Not sure if anything can be done about the odor. Thus I am reaching out to the forum.

I am looking for ideas/help to help vent the smoke upward and away from me. Right now, I wear a respirator due to the smoke. I do not run a hot pot, so there are no lead fumes. I am so accustomed to the odor that I no longer notice it, but there is indeed an odor and it is not like grilling hamburgs! I have in mind placing an exhaust fan above my pot so that it is about 6 feet off the ground. I envision fashioning a stand for it out of metal (long, vertical legs and wheels for ease of moving it around). I would even invest in something more powerful meant to exhaust smoke if it would work, but those machines are very pricey even on Ebay (easily $1000-$2000). I could justify the cost because I would no longer be paying monthly rent. But I rather try something less expensive! I think if the smoke is passed through a fan and swirled around, it may help with the odor..(?).. I don't know.... Also, wearing my respirator would add to the angst of any prying eyes as to what I am cooking! Thus, I think if I can safely NOT use a respirator, the neighbors may not think the worse other than their hoping they don't get invited to the barbeque. I would smelt the lead on a weekday, during the day (probably mid morning) and do it for maybe 1 hour. And not every day. Although it is OK to smelt wheel weights and other lead (no open flame), I am mindful of the odor that will waft in the air but am thinking it will be less if I swirl it around via a fan.

All suggestions/advice are welcome.

Thank you!!

I have attached 2 pictures of my propane cooker. The 1st picture shows a light above the cooker. I used a 90 degree elbow for a section of pipe that it is attached to. And the other section, fits into another piece of pipe that is cemented in a 5 gal. bucket. But I will not be using a light if I have to move to another area, and it is residential as noted above.

~ Kathie

[jsizemore]

A smaller commercial kitchen exhaust fan with a variable speed control and some duct should take care of your needs. Some give you the option of roof or wall mount. With enough air volume you should be able to "hide" the evidence. Even new you should be able to keep the cost well under $1000 if you do the work.

[SciFiJim]

Smelting midmorning on a weekday should probably suffice to keep from offending the neighbors. I also do mine in the backyard and anyone watching while not invited to do so is snooping. I don't use a respirator, I just stand upwind.

Using sawdust as a flux and lighting the smoke on fire also takes care of a lot of the fumes and smell.

[JBinMN]

I have been casting out doors so the wind does the work for me for some time now. I just recently got an "inline" fan that is very similar to this one in the link below to set up for casting/smelting in the garage. Total expenditure is less than $100. ( prolly even less than that , just have never totaled the amount, but it surely is less than $100) That is the fan + ducting/elbow to shoot outside & not thru the roof, etc.

https://www.amazon.com/VIVOSUN-Inline-Booster-Noise-Grounded/dp/B01C82SZRM/ref=pd_lpo_vtph_86_lp_t_3?_encoding=UTF8&psc=1&refRID=H90QNFV9B6C2XJWB1M4B

Perhaps something like that would suit your needs?

Anyway, it is a suggestion.

G'Luck!
:)

[RogerDat]

Height and air flow are your best assets. See if you can nab an old furnace squirrel cage blower with motor. Duct that up as far as is practical. Use a reducer to increase the velocity so the smoke goes even higher and has more chance to spread out and dissipate before coming back down around people.

Ask around at furnace repair/replacement businesses. Lot of furnaces get replaced for burner/heat exchanger issues and still have good blowers. If working in a garage don't forget it takes air coming in to allow blower to move air out.

Not sure what the duct work would run. An attractive vent cover comes in at $50 or less
https://www.homedepot.com/p/Broan-16-75-in-x-16-75-in-Aluminum-Automatic-Gable-Square-Mount-Louvered-Shutter-Attic-Vent-433/203481754

But straight up with a cap costing less than $20 would possibly allow getting the smoke/odor higher and more spread out.
https://www.homedepot.com/p/7-in-Vent-Cap-VC7/100135124

No idea what a used furnace blower and motor would cost but I doubt it would be very expensive. I was figuring on asking around $25 or $30 for one going into a garage sale and that was mostly on account of the electric motor. Later model hot water heaters use a blower too for the exhaust chimney, might be able to nab one of those used, or a cheap one new. They move air fairly well. Cheap range hood can be ducted too. Not sure how well it would spread it but if it pulls enough smoke etc. away from your work space that you don't need a respirator or allows you to direct the smell in the least offensive direction that might offer a solution. Remodelers often tear them out to put a new kitchen in. Might let some know you are looking for a nice big one.

I used a squirrel cage furnace blower just mounted to the rafters in the garage and blowing horizontal out the garage door as a welding "hood" did the job without duct or hood. Would blow out a lighter at the doorway from the back of a 30 ft. garage. Welding smoke mostly went out the door without air blowing at my weld and messing with my arc envelope. That was from a larger furnace in a small manufacturing plant but even a small household furnace sized one really moves some air.

[JBinMN]

I have one of those in my rafters in the garage also, RogerDat, and it is a good idea.
:)

I use it for getting the hot air out in the Summer & not for smelting/casting, but it is a very good idea if someone wants to go to the effort.
:)

I just wanted to keep it very simple myself & inexpensive. Just for a small area & directly vented out the side.
I am not sure, but the rigging up a squirrel cage blower with the venting might be a bit more expensive, but it will sure move a lot of air.
;)

[Mr_Sheesh]

I've built more than one "fume hood" in past for a lab processing precious metals ores. Trust me, the stuff we were running there is a LOT worse than lead fumes - Hydrogen Sulfide, that sort of thing, it EATS metal ores but a single medium whiff of it and you're DRT. So we made sure it WORKED.

Use a squirrel cage fan, and a stove pipe or the like; Make sure that any air moved by the pipe will go past your melting rig and go right out the pipe - You don't want to be breathing the stuff. Take the output of the squirrel cage fan and pipe it up to the top of the stove pipe (tho since you aren't using as nasty of stuff as we are, you could do this at a lower level - We would have EATEN the fan had we used it in the lab as a air source, acid fumes and the like.)

Where ever you inject the air from the squirrel cage fan, you want to use an Eductor (I am having a hard time finding a good illustration of one. Basically - You blow PAST the outside of the stove pipe with the squirrel cage's fan, that drags the air in the stove pipe along with it; Dredges use the same principle but usually use one single jet inside the dredge pipe to do the same thing. You just want the injected air to be aimed UP the pipe, that's what's critical, it will then drag the rest of the air with it, venting your smelting area.)

This has also been used for laser cutters (which generate some nasty smoke, especially when cutting Lexan / Plexiglass etc.) and so on.

If I can help or you need a different explanation just PM me, or ask here; It's easier than my explanation may make it seem. (I know, I can make peoples' eyes glaze over with a mere 20-30 words - Sorry!)

[TheCaptain]

A smaller commercial kitchen exhaust fan with a variable speed control and some duct should take care of your needs. Some give you the option of roof or wall mount. With enough air volume you should be able to "hide" the evidence. Even new you should be able to keep the cost well under $1000 if you do the work.

Thank you!

[TheCaptain]

Smelting midmorning on a weekday should probably suffice to keep from offending the neighbors. I also do mine in the backyard and anyone watching while not invited to do so is snooping. I don't use a respirator, I just stand upwind. Using sawdust as a flux and lighting the smoke on fire also takes care of a lot of the fumes and smell.

Thank you.

[TheCaptain]

Thank you everyone who has responded so far. ~ Kathie

[TheCaptain]

I've built more than one "fume hood" in past ... If I can help or you need a different explanation just PM me, or ask here; It's easier than my explanation may make it seem.

Thank you. I will send a PM. ~ K

[TheCaptain]

I have one of those in my rafters in the garage also, RogerDat, and it is a good idea.... .... I am not sure, but the rigging up a squirrel cage blower with the venting might be a bit more expensive, but it will sure move a lot of air. ;)

I think I understand both of you, and RogerDat's venting welding smoke. For me, is it possible for me to safely smelt in the garage with propane using the venting in the rafters?? I would think that I would have the garage door be open...?... Would I have the propane tank situated outside the garage? I do have a heater (that looks like a cannon) from Home Depot that I use to heat my garage when working in it and I have carbon monoxide detector. It would really love to smelt in the garage if it can be done safely, with smoke being exhausted out through the roof... out of sight, out of mind! Hoping you can give me some more information to see if this is at all safely possible. I was reading up on exhaust vents yesterday, and found information on people having grills in their 3 season porches properly vented to the outside, so it seems possible. Thanks!

[TheCaptain]

I have been casting out doors so the wind does the work for me for some time now. I just recently got an "inline" fan that is very similar to this one in the link below to set up for casting/smelting in the garage. Total expenditure is less than $100. ( prolly even less than that , just have never totaled the amount, but it surely is less than $100) That is the fan + ducting/elbow to shoot outside & not thru the roof, etc.

https://www.amazon.com/VIVOSUN-Inline-Booster-Noise-Grounded/dp/B01C82SZRM/ref=pd_lpo_vtph_86_lp_t_3?_encoding=UTF8&psc=1&refRID=H90QNFV9B6C2XJWB1M4B

Perhaps something like that would suit your needs?

Anyway, it is a suggestion.

G'Luck!
:)

This sounds like a possibility! Is it possible for you to post a picture? If I see it, then I can better picture how you have it set up. Does the ducting go through the wall or you just have it aimed outside (assuming you have garage door or a door or window open??) ... if not a picture, a bit more detail as to how you have this set up. I just can't picture how the fan and duct are "hooked up" /situated over your pot. Getting the parts is not a problem, but how to put all this stuff together is a problem for me because I can't visualize how to do it. Thanks in advance for further information!!! ~ K

[TheCaptain]

Thank you all for great ideas. I understand what parts are needed, but it would be so helpful to see a picture of complete set up (smelting pot and fan and/or duct, etc). Thank you! I am now getting very encouraged about doing this in a residential area...and if I could only see what some of you have done, or see a drawing, I would be on my way to home plate. Right now, I feel I have made it to 3rd plate. I can't thank everyone enough. ~ K

[Grmps]

Find a person in your area that does sheet metal who reloads and do a trade with him. I would build a smelting booth not too much taller than the top of your pot. then put a vent fan at the peak venting it out the wall and as high up in the air as the law allows (you may need guy wires) to disperse the fumes. to get good air flow going out you will need air coming in say at the bottom of the booth to create a good draft and help the fire burn without taking oxygen out of the garage. I would consider putting metal doors on the bottom of the booth and maybe plexiglass in the middle to help contain the fumes and help with venting.
I would also suggest a rheostat (speed controller for the fan) so you don't run it any faster than you need to.

You could build the booth out of 2x2, screw tin to the inside and call that good.

[JBinMN]

I will let RogerDat describe his set up as the one I have is pretty primitive & is meant for just moving air to cool, not for venting fumes. Although I bet it would work for that.

I can't yet show you pictures of "my" setup that I described, as I have not yet installed the whole thing. I can show you the parts I gathered ( all new) , but I have not installed it yet, due to the Winter cold we have had here. Between that & my health issues, have not yet assembled & installed it. I smelted & cast enough last Fall to last thru Winter for my current shooting needs.

I can certainly take some pics once I have it assembled, as well as installed, if you like & are not in a big hurry. I am planning of trying to get it done in the next month or so.

Best I can do, I reckon.
:)

[Paper Puncher]

Kathie

There is no reason you can't smelt in your garage. It just requires a properly constructed setup.

Your on the right track looking at things like indoor BBQ's and smokers. Take a look at images of fume hoods or small paint booths. They are enclosed on three sides to contain the nasties. If you do something like that it will help in keeping fumes from spreading in your garage and directs them away from you. Your pot is a heat source. So if close to a wall, set it up like a wood burning stove, eg cement board against combustible walls to reduce clearance.

There is an old saying "The answer to pollution is dilution". The more air you move through your vent system the more diluted and less obvious any smoke or smell will be. I think what Mr Sheesh is describing is a venturi type venting system. The fan is not in the pots exhaust stream. You create a Y connection and the air blown by the fan creates a low pressure area on the second leg of the Y sucking the fumes out of your hood. There are a lot of advantages to this type of system.

A few more things.

The cage on squirrel cage fans need to be cleaned occasionally. In a furnace they are moving filtered air. The dirtier the environment the more often they need to be cleaned. If placed above your pot in the exhaust stream don't forget to consider access.

Any time your exhausting air you need make up air. Opening a window or the garage door a small amount should be more than adequate.

[Mr_Sheesh]

Yes, that's a good name to call it too. You could (so long as you're just dealing with lead smelting) just use the squirrel cage fan directly, really, you aren't going to have anything there that will eat the fan in minutes to hours, unlike what we were working on. Squirrel cage fans are usually built for long use, just lubricate the bearings (zirc fittings or the like usually)

You want a fair bit of air flow, aka a LOT of air flow, so the air you are breathing is a steady wind towards you, you want an air change a minute or so in there, basically enough air flow so that any fumes emitted are blown up the vent pipe instead of hanging around where you can breathe them.

[lightman]

I'm sorry to hear that you may loose your present place.

I smelt inside my 30 X 30 ft shop. One end has a 10ft wide overhead door and I have a 36 inch exhaust fan on the opposite end in the gable. I also put my 48 inch floor fan near the walk in door, working together with the gable fan. I'm in town, although on the edge and I'm on a 150ft lot, as are the other neighbors. I've had no complaints about the smoke from anyone and it doesn't appear to be very obvious in the yard. I try to light any really bad smoke which seems to help.

Safety wise, the two fans seem to provide plenty of ventilation. You can see the smoke being quickly moved to the exit. I also stay and work on the up wind side of the pot. I don't wear a face mask or respirator but I do exercise good hygiene. I also wear boots, jeans, long sleeve flame retardant shirt, safety glasses and leather gloves. But you already know about proper dress!

To reduce any mess and make clean up easier I set everything on a 4X8 ft sheet of plywood. I know you have smelted probably more than I have but I hope these ideas have been some help!

[Mr_Sheesh]

Wait, we aren't supposed to wear an all Nylon and Rayon short sleeve & shorts outfit when casting? No one told me! :P

[TheCaptain]

I will let RogerDat describe his set up as the one I have is pretty primitive.... I can certainly take some pics once I have it assembled, as well as installed, if you like & are not in a big hurry. I am planning of trying to get it done in the next month or so. Best I can do, I reckon.
:)

Thank you. If the spirit moves you when all assembled, I would love to see pictures! Hopefully I will be in further contact with RogerDat ~ K

[TheCaptain]

Kathie

There is no reason you can't smelt in your garage. It just requires a properly constructed setup......Any time your exhausting air you need make up air. Opening a window or the garage door a small amount should be more than adequate.

Thank you for the great information! ~ K

[TheCaptain]

.... I try to light any really bad smoke which seems to help. .....Safety wise, the two fans seem to provide plenty of ventilation. You can see the smoke being quickly moved to the exit..... but I hope these ideas have been some help!

Yes, your ideas are of help! Can you clarify what you mean by "light any real bad smoke" ???? My garage is approx 20x20 with 2 separate overhead doors. Where do you have your pot set up in your shop relative to the rear and the front?

Thanks!!!

~ K

[Livin_cincy]

Welding indoors requires ventilation per OSHA.
This is done with air changes per hour in the room or Filtration.

The key to ventilation is AIR IN = Air OUT.
Nobody likes to have doors & windows open in the winter so the systems do not work well or at all.
Ductwork is up high drawing smoke up. The draft is not strong enough to carry particulate.
I forget the number of Air changes required.

There are portable " Smog Hog " devices that suck fumes thru an flex hose arm near the source of the fumes. The air & smoke are drawn into the machine and thru a HEPA filter back into the room. So no thermal energy (heat) is lost and they can be used year round.

A household dryer exhausts 20 Cubic Feet of Air Per minute (CFM). That is 20 x 60 = 1200 Cubic Feet per Hour. So 1/8 of the air inside a 1200 sqft house with 8' ceilings is exhausted when you dry 2 loads of laundry.

If you build a 5x5x8 foot enclosed area (200 Cubic Feet) and drop a 75 CFM bathroom exhaust fan on top and run duct out of the space you will be exhausting 75 x 60 = 4500 Cubic Feet of Air per hour. This gives you 4500 / 200 = 22.5 air changes per hour.
You will actually need (2) Bathroom fans. One to blow air into your enclosed area at floor level and the second to exhaust from the back side away from you. For safety interlock these so they both always run.

Good Luck.

[TheCaptain]

Wait, we aren't supposed to wear an all Nylon and Rayon short sleeve & shorts outfit when casting? No one told me! :P
:goodpost: [smilie=l:

[TheCaptain]

.... The key to ventilation is AIR IN = Air OUT. ..... If you build a 5x5x8 foot enclosed area (200 Cubic Feet) and drop a 75 CFM bathroom exhaust fan on top and run duct out of the space you will be exhausting 75 x 60 = 4500 Cubic Feet of Air per hour. This gives you 4500 / 200 = 22.5 air changes per hour. You will actually need (2) Bathroom fans. One to blow air into your enclosed area at floor level and the second to exhaust from the back side away from you. For safety interlock these so they both always run. Good Luck.

Thank you for a very detailed and scientific reply! You know your stuff! For my situation, I would be in an approx. 20'x20' garage. I don't have the knowledge to even begin on making calculations for this larger space!! Also, 5'x5' footprint is not enough space for me with my setup. As it stands now, I am over "coverage" so if I were to build anything new on my property, I would have to get a variance.

I thank everyone to date for taking the time to help me make an informed decision as to the best way for me go. I am still welcoming all thoughts on the matter. I have learned a lot.

[Mr_Sheesh]

https://en.wikipedia.org/wiki/Air_changes_per_hour I would go with the Laboratory category and 6-12 air changes per hour, OR MORE. And ideally you want a fume hood as in https://en.wikipedia.org/wiki/Fume_hood - If you can put your whole smelting setup inside such a hood, and pop the front cover upwards to refill it, you will be safer if visited by the Tinsel Fairy, plus you will have basically NO exposure to lead fumes. But do what works, if the pot is on a bench and the exhaust is right above it, the exhaust should suck up the vast majority of the fumes right away and the rest pretty quickly. If you end up with 22.5 air changes per hour, well, that's a nice extra safety margin, I'd approve of it :) Once I move I'll put a scrubber tower up for the laser engraver/cutter I own (at a friends place currently) and probably use that same vent for casting. that'll be nice :)

And TY TheCaptain :)

(You don't have to get a CPAP machine and use a hose from that to push air into your hood over your head, we did that in that initial chem lab too, one of the guys was an idiot and had breathed so much acid fumes etc. that his teeth were etched badly by them - That could NEVER have any other negative health effects - Riight... They had a vent system, just felt it was too much bother to use... Lead fumes are "relatively benign" compared to H2S, SO3, and the other chemicals we used to rip ores apart. I won't recommend breathing any of the above though! Even the fumes from SSN - Salt Saturated Nitric Acid - will purely ruin your week. This is why chem labs have fume hoods, so chemists live more than to age 30 or so LOL)

[lightman]

Wait, we aren't supposed to wear an all Nylon and Rayon short sleeve & shorts outfit when casting? No one told me! :P

Stand by, I'll post up some pictures of me casting while wearing my speedo, flip flops and wife beater! [smilie=s:

[lightman]

Yes, your ideas are of help! Can you clarify what you mean by "light any real bad smoke" ???? My garage is approx 20x20 with 2 separate overhead doors. Where do you have your pot set up in your shop relative to the rear and the front?

Thanks!!!

~ K

I actually will try to light any smoke that is produced. Sometimes it will burn and other times it won't. If it will burn it seems to produce less smoke. Kind of like when you flux with wax or saw dust.

Houses in my neighborhood are mostly on 150 ft lots and I have had no complaints about my smoke. I can see smoke outside on occasion, but usually only when there are a lot of really greasy or painted weights. Stick ons are particularly bad to smoke.

I place my burner near the end of the shop near the exhaust fan. There is a walk in door near that end also and I'll put my floor fan near the door, where the 2 fans can work together. If you have 2 overhead doors one of those floor fans might provide you with enough exhaust to be safe. You can change the speed of the airflow a little by lowering the doors part way.

I feel a little odd offering you advice on smelting. While I've smelted a lot of lead I probably can't compare to your experience. I hope something I have posted will be of some help.

[TheCaptain]

Thank you Mr_Sheesh!

[TheCaptain]

I hope something I have posted will be of some help. Thank you! YES... a big help! I am going to send you a PM.