Air born dust collection?

The most important thing to remember is after you have ground/ Shaped a few handles and or any other flammable material is to dump out all of the wood shavings etc, out of your collector system & blow out any filters ,,, Before you start grinding any Steels !!! That’s how you start fires! Ask me how I know?:rolleyes:
 
joedhiggins said:
If you work in a shop with garage doors or the like, I don't find air purification all that useful. I wear a respirator in most dust producing tasks, so I am not worried about breathing it in while I make it. I generally will pop the garage doors for a few minutes (I live somewhere with some wind and I have doors on both sides of the garage) to evacuate the air after a task that produces dust. When grinding knives, you really only neet to worry about the abrasives and some of the handle materials. The steel itself wont be airborne for more than a minute or two.

For knife work, there are a bunch of options but a decent bucket style cyclonic filter with a water filled bucket underneath the separator and a collection hood beneath the platen is probably the best way to go. Only thing that perhaps would reduce the need for the respirator would be a coolmist system in conjunction with the seperator, but I would still wear one to be safe.

Either way, you dont really have to worry about the dust on the floor, the particles are all far heavier than air, and settle out. Just sweep up regularly and you are fine. The dust collection is for convenience and cleanliness more than safety.
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OMG.... this couldn't be more wrong. You absolutely have to worry about dust settling after you grind. Steel can be airborne for a LONG time.... especially the dust that is the most dangerous! The simple act of walking kicks up fine particulate. Opening a big garage door just blows it into corners, away from proper disposal.

I'm sorry for overreacting but HOLY SMOKES that is some bad advice. I fear for your lungs, dude. Respirator or not.

Air movement is your enemy with dust management. Fans, brooms, airguns are dangerous tools to battle harmful particulates.

A collector hood under the platen is picking up mostly the big stuff. The fine particulate is swept away with the current of the moving belt. If your intention is to capture the dust that does the most harm, you need a shroud around your grinder with a semi-enclosed loop removal system, either gathered by a localized collector or exhausted out of the room.

Clean up with a shop-vac, not a broom and pan, wipe down tops of benches and machines with a damp/oiled cloth. Air filters are okay but make sure they don't kick around dust as they work. Maybe have them on a timer after you leave. Wipe all surfaces when you return to the shop and everything has settled.

This is an old thread I made. My current system is improved but this gives you the idea.
https://www.bladeforums.com/threads/i-made-a-dust-evacuation-system-for-my-grinder.1157981/
 
Rick Marchand said:
OMG.... this couldn't be more wrong. You absolutely have to worry about dust settling after you grind. Steel can be airborne for a LONG time.... especially the dust that is the most dangerous! The simple act of walking kicks up fine particulate. Opening a big garage door just blows it into corners, away from proper disposal.

I'm sorry for overreacting but HOLY SMOKES that is some bad advice. I fear for your lungs, dude. Respirator or not.

Air movement is your enemy with dust management. Fans, brooms, airguns are dangerous tools to battle harmful particulates.

A collector hood under the platen is picking up mostly the big stuff. The fine particulate is swept away with the current of the moving belt. If your intention is to capture the dust that does the most harm, you need a shroud around your grinder with a semi-enclosed loop removal system, either gathered by a localized collector or exhausted out of the room.

Clean up with a shop-vac, not a broom and pan, wipe down tops of benches and machines with a damp/oiled cloth. Air filters are okay but make sure they don't kick around dust as they work. Maybe have them on a timer after you leave. Wipe all surfaces when you return to the shop and everything has settled.

This is an old thread I made. My current system is improved but this gives you the idea.
https://www.bladeforums.com/threads/i-made-a-dust-evacuation-system-for-my-grinder.1157981/
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How do you feel about pentz's diy air cleaner as a way to combat fugitive and floating dust while it's in the air https://wynnenv.com/products-page/woodworking-filter-pricing/13f230nano/ ? I'm waiting on the filter, the Wynn 230 square foot merv 15 https://wynnenv.com/products-page/woodworking-filter-pricing/13f230nano/ and I scored the vortex vtx800 cheap on ebay, 1000 cfm in line fan.

Obviously not a replacement for capturing dust at the source, but it seems exponentially better than any ceiling mounted unit available that's anywhere near that price range.

Do you have a dylos pro? Curious what your reading are with your system.
 
I did have someone test the air in my shop. I'm not sure what they used but it gave two readings... large and fine particulate ... <2.5 micron and >2.5 micron. They were contracted to test the newly renovated Opera House in town.... he was a knife guy... lol

The readings in the center of the shop were 109 and 15
5 minutes of my system on it went to 225 and 22 ... then dropped down to 125 and 19
after 20 minutes of grinding it read 520 and 33
10 minutes after I stopped grinding(system still on) it was 220 and 21

we turned off the filter and started the grinder... 800 and 45
I ground for 5 minutes... 5200 and 270!
left for 10 minutes and came back in... 2500 and 180!
swept the floor... 2900 and 212!

Funny enough, when we went outside, it read over 3500 and 400!!! But the guy reminded me that it was now reading organic materials like pollen, smoke, etc...

I don't really know how to read or compare those numbers, other than the system significantly dropped them in my shop. The guy had equipment that measured to a higher accuracy and separated for mold, dust and a bunch of other stuff... even gases... but it was expensive company machinery and we were off the job site. The meter he used was about the size of a 6-pack of beer and he could not hold it to do the reading. It had a fan intake and had to be stationary.
 
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Rick Marchand said:
I did have someone test the air in my shop. I'm not sure what they used but it gave two readings... large and fine particulate ... <2.5 micron and >2.5 micron. They were contracted to test the newly renovated Opera House in town.... he was a knife guy... lol

The readings in the center of the shop were 109 and 15
5 minutes of my system on it went to 225 and 22 ... then dropped down to 125 and 19
after 20 minutes of grinding it read 520 and 33
10 minutes after I stopped grinding(system still on) it was 220 and 21

we turned off the filter and started the grinder... 800 and 45
I ground for 5 minutes... 5200 and 270!
left for 10 minutes and came back in... 2500 and 180!
swept the floor... 2900 and 212!

Funny enough, when we went outside, it read over 3500 and 400!!! But the guy reminded me that it was now reading organic materials like pollen, smoke, etc...

I don't really know how to read or compare those numbers, other than the system significantly dropped them in my shop. The guy had equipment that measured to a higher accuracy and separated for mold, dust and a bunch of other stuff... even gases... but it was expensive company machinery and we were off the job site. The meter he used was about the size of a 6-pack of beer and he could not hold it to do the reading. It had a fan intake and had to be stationary.
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There is nothing about organic materials that make them less dangerous than inorganics. Infact, the reverse can be true. Air evacuation is not your enemy against airborne particulates. It can kick up dust, and that is why you should sweep/vacuum. Look, reasonable precautions and dust collection are a good idea, but we aren't talking about sarin. Just wear a respirator with the proper filter and clean up and you will be fine. I am not saying that you can't or shouldn't run more complex dust collection, but the idea that you are incurring a meaningful level of risk if you don't have crazy hooded dust collection and realtime filtration is sensationalist and unsubstantiated. Our fine particle crystalline silica concentrations are not nearly high enough to exceed the max safe levels while wearing a half mask. Unless you are burning kaowool or something silly, and perhaps not then.

Cleanliness, a good respirator, and scheduled filter swaps are all you need. Make sure your filters are appropriate for what you are dealing with. All the rest are nice to have, can add convenience, and may be a good idea if you show allergic reactions or the like. But the idea that you need thousands in dust collection or your shop time is hastning a grizzly death isn't supported.
 
If you go with the 3 Hp Grizzly, you can stick with 6" or 7" ducting and those bends are fine. If you go with the smaller system and the Super Deputy, and 5" ducting, I'd try to straighten out at least 1 bend. Go with the bigger system if you can, you really need to move 1,000 CFM to get the fine dust, and as Rick said, hood design matters too. Be aware that you need the same cross sectional area of free air going in to your hood, as you have in the duct. Otherwise your hood will "starve" the duct for air.

With duct that short, and no filters, you might over-amp the 3 Hp Grizzly. But if you add a spark trap inline, that will probably solve that. I will advocate for the Nordfab style Quick Disconnect ducting. When I set up my systems, the Nordfab spark traps were available at a reasonable price with a fairly short lead time. So I splurged and went with Nordfab duct too. Some parts from Grizzly, but factoring in shipping, the straight duct and some other bits were cheaper at the local McMaster-Carr. It is so much easier to change and adjust than the spiral duct we have in the woodworking area. But the price is painful...

You don't really need a big drum to collect grinding dust. 5 gallons will be plenty heavy to carry to the trash, and you should be emptying fairly often to prevent fire. But if you use a 5 or 10 gallon bucket for the cyclone to empty into, you will need a vortex breaker between the cyclone and the drum so the dust in the drum does not get stirred up and end up in the filters.
 
joedhiggins said:
There is nothing about organic materials that make them less dangerous than inorganics. Infact, the reverse can be true. Air evacuation is not your enemy against airborne particulates. It can kick up dust, and that is why you should sweep/vacuum. Look, reasonable precautions and dust collection are a good idea, but we aren't talking about sarin. Just wear a respirator with the proper filter and clean up and you will be fine. I am not saying that you can't or shouldn't run more complex dust collection, but the idea that you are incurring a meaningful level of risk if you don't have crazy hooded dust collection and realtime filtration is sensationalist and unsubstantiated. Our fine particle crystalline silica concentrations are not nearly high enough to exceed the max safe levels while wearing a half mask. Unless you are burning kaowool or something silly, and perhaps not then.

Cleanliness, a good respirator, and scheduled filter swaps are all you need. Make sure your filters are appropriate for what you are dealing with. All the rest are nice to have, can add convenience, and may be a good idea if you show allergic reactions or the like. But the idea that you need thousands in dust collection or your shop time is hastning a grizzly death isn't supported.
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Maybe if you are only in the shop a couple times a week the accumulative damage won't show itself. I am in my shop 8-14hrs a day. If I was as nonchalant about dust as you seem to be, i'd be in trouble by now. I personally know four people with respiratory issues directly due to metal/epoxy dust, one maker who has had part of his lung removed and a boat builder acquaintance who resides 6ft under from long term exposure to epoxy and wood dust.

Perhaps, I am overly cautious... Or perhaps it was the fact that the gentleman who works for a company that assesses air quality told me that I wasn't being cautious enough. He seemed to be in a hurry to leave the room after we shut the exhaust system down and the readings skyrocketed. He also told me that opening the door would just make it harder to clean.

https://lunginstitute.com/blog/can-breathing-metal-dust-hurt/
https://www.ccohs.ca/oshanswers/chemicals/lungs_dust.html
 
I do understand that you are wearing a half mask... that is really good. But unless you keep it on after you grind or clean up, you aren't protecting yourself from the dust you don't see. As someone pointed out, it can stay airborne for days and get kicked up when you walk past benches and turn on machines.

The OP wanted to know what he could do to minimize the risks for he and his wife. Unless she is wearing a half mask as well, I would think that his needs go beyond PPE and step into air quality management. But again... how often is the exposure? Can he work one night, let it rest and carefully clean the next morning? Sure.
 
Rick Marchand said:
I do understand that you are wearing a half mask... that is really good. But unless you keep it on after you grind or clean up, you aren't protecting yourself from the dust you don't see. As someone pointed out, it can stay airborne for days and get kicked up when you walk past benches and turn on machines.

The OP wanted to know what he could do to minimize the risks for he and his wife. Unless she is wearing a half mask as well, I would think that his needs go beyond PPE and step into air quality management. But again... how often is the exposure? Can he work one night, let it rest and carefully clean the next morning? Sure.
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Totally hear your concerns. I completed the air cleaner last night and the thing works well, brought the particulate levels down from 4000 on the dylos to under a 1000 in 15 minutes. One caveat is that is jumps back up when you turn it off, but it will still be effective as added protection while I'm working with a respirator on.

I've decided to enclose myself and the grinder in a sort of pvc paint booth, with welding curtain walls and ceiling. That I think should help contain the spread, and I will be cleaning with a dewalt self cleaning hepa vac.

This seems like a reasonable step as I have a method of monitoring sub micron particulate levels (to some degree). The next step is to spend the $1500 on a 240v sub panel, drop, dust collector, cyclone and ducting.

Nobody besides myself is spending any time in the garage, aside from stepping in to load/unload the washer and dryer. If I can keep the resting particulate levels around 2000 at worst, I think that should be fine.

Edit: just wanted to add that I really only work on knives on the weekends, maybe an hour or two during the week.
 
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I wanted to chime in on this topic. I can only agree with what has been said already by more knowledgeable people than me.
Best case scenario for this kind of work in my opinion is having your grinding area seperated from the rest of your workshop if possible, wearing a proper respirator, having a dust collection directly at your grinder that has an adjustable funnel to be able to position it directly below the spot where you hold your workpiece and a filtration unit at the ceiling that cleans the airborn particulates when you are done working.

Also when mentioning respirators: make sure you get proper filters for particulates and gases. For example grinding micarta can release formaldehyde, make sure you get a filter that covers that. I very much doubt formaldehyde concentrations would reach seriously harmful levels when shaping some micarta handles for example, but the key thing there is long time exposure I think.

I was curious however as to how long you guys wear your respirator at a time when you are working? I've read that, for example when wearing a full mask, a working time of about 1,5-2 hours with a break of 30min is recommended. Is that something you do in practice?
 
I don't have an answer for your question, but I suggest that you buy a dylos pro particulate meter to reduce some of the guesswork involved. It wont tell you much, but it will tell you how much is floating in the air at that point in time.
 
The Idea of separating the grinding area is really wonderful because the dust particle which flew while Grinding may make dusty to other areas. Instead of building walls besides them Industrial Plastic Curtains is the best idea.

Moreover, Only removing apron is not sufficient enough you should take bath because the particles which flew in air while grinding they get stuck to the body which may cause itching on your arms.

If you are thinking to buy Industry Plastic Curtains for your separation. I would recommend AKON Curtains for Purchase because they provide proper customization and also guide customers with detail of each and every curtain role.
 
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