General welding questions that dont fit in TIG, MIG, Stick, or Certification etc.
JustTheDad
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tweake wrote:the problem is all the particles. which is why its not a good idea to have your range hood connected to the hrv/erv system in the house.

really need to have a fume extractor which filtered out the particulates. then let the buildings ventilation system do its thing to remove the bad gases.
Thanks for that detail Tweak
My set-up is much less sophisticated than you give me credit for : )
I got a free range hood on CL and mounted it vertically next to the welding table. That is ducted to the outside and is only good for 400 or 500cfm. I just open a window or door on the other side of my basement to let air in. We're just TIG welding and very rarely MIG down there, so it keeps the air clean. Our HRV is for the upstairs floors.

One last question though. I thought the fume extractors also filtered some of the gasses/smoke and not just particulates. Is that incorrect?
cj737
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JustTheDad wrote:
tweake wrote:the problem is all the particles. which is why its not a good idea to have your range hood connected to the hrv/erv system in the house.

really need to have a fume extractor which filtered out the particulates. then let the buildings ventilation system do its thing to remove the bad gases.
Thanks for that detail Tweak
My set-up is much less sophisticated than you give me credit for : )
I got a free range hood on CL and mounted it vertically next to the welding table. That is ducted to the outside and is only good for 400 or 500cfm. I just open a window or door on the other side of my basement to let air in. We're just TIG welding and very rarely MIG down there, so it keeps the air clean. Our HRV is for the upstairs floors.

One last question though. I thought the fume extractors also filtered some of the gasses/smoke and not just particulates. Is that incorrect?
If your fume extractor is vented to the outside then there is no need to "filter" the air being expunged. If the extractor is a standalone unit and recirculates the air back into the workshop, then a filter is used.
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JustTheDad wrote: One last question though. I thought the fume extractors also filtered some of the gasses/smoke and not just particulates. Is that incorrect?
Mine has a HEPA and a charcoal filter
Richard
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tweake
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JustTheDad wrote:
One last question though. I thought the fume extractors also filtered some of the gasses/smoke and not just particulates. Is that incorrect?
smoke is made up of particulates so it filters the particulates out of smoke.
however they do not do anything to gasses unless it has a charcoal filter which will take out some of the gases. you always need some form of fresh air ventilation.
tweak it until it breaks
JustTheDad
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Then why spend thousands of dollars on a fume extractor when a DIY dust collector and some hepa filters can take out particulates?
cj737
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JustTheDad wrote:Then why spend thousands of dollars on a fume extractor when a DIY dust collector and some hepa filters can take out particulates?
Likely it has lots to do with the strength of the blower motor, engineered recirculation, volumetric, and self-enclosed structure. On the surface they may seem the same, but a deeper analysis or side-by-side performance evaluation would likely show the delta. For a DIY, Home shop, some practical guidance, a bit of cobbling, you are probably quite fine. For a production shop, no way. Likely OSHA and other Employment protections come into play that require certified hardware (as it should).

If your argument is why buy anything "pre-made" versus DIY, then I think you'll be circling that argument for decades to come 8-)
Poland308
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They actually have to go around the fab shop for the company I work for to do air samples for things like hexavelentchromium .
I have more questions than answers

Josh
tweake
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JustTheDad wrote:Then why spend thousands of dollars on a fume extractor when a DIY dust collector and some hepa filters can take out particulates?
from what i've seen compared to say wood dust extractors, welding fume extractors needs to handle the heat, usually far more air flow and i think a lot finer filtration.

however welding fume extractors seam awfully expensive for what they are.
tweak it until it breaks
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Jim Bridger wrote:Hey All -

I used Jody and his videos to teach myself how to Stick, Mig, and Tig weld and have had a lot of fun doing it. It was a goal at first just to fix our farm equipment, corrals, etc. but it turned into welding whatever I could come up with (furniture, tools, etc.). Anyway, I have small shop that I operate out of but it is also used for storing our tractor equipment for the winter. I'm wondering if someone can help give me their ideas on how they installed ventilation and/or air filtration. I have neither and certainly have concerns from both weld fumes and from grinding. I wear a respirator when doing big project (admittedly not religious about this...) and also have setup some basic box fans with air filters on back but obviously it's not the best solution and doesn't address fumes. Summer its easy to leave the doors open unless there is a breeze but winter is coming. Shop is about 30x30 and about 15' high ceilings. Any help is MUCH appreciated!
Jim I have no idea don't know if this is an option for you or not since you guys get some serious cold there but a really easy set up is to try to score a old air handler or gas furnace and duct the supply end straight out of the shop and run a flex duct to your work area, even just the blower will work if you build a box around it. a filter isn't 100% necessary since it is venting directly outside but the blades of the blower wheel will collect debris and become what we call cupped, so full of debris that they can't move air. it would take quite awhile for that to happen though and is easily cleaned.

good luck.
the heck with the duty cycle on the welder, tell me about the duty cycle on that grinder !!
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