Confining Plasma CNC Dust

[chrisj380]

Hi,
I have a plasma CNC and have enclosed the bottom to confine most of the materials under the table. The dust is so annoying and makes a huge mess. I have a whole cut underneath table with a good exhaust fan blowing allot of the dust outside. Where my shop is located now is a nicer spot and has asphalt lot. I now cannot blow dust outside and have purchase a roll around magnet to pick up most of the dust after it settles. Its just a huge mess. I thought if i build a room for my grinding and CNC that would confine the dust. I ran into the same problem just smaller. How to vent the room. I was thinking of something i could mount inside or outside the room where i can filter the dust out. Not sure how to do this. I'm open to suggestions.
Thanks, Chris

[Capstone]

Putting a Water Table on the machine will cut down on some of the dust, but I agree it's a problem. My entire garage has a layer of dust everywhere. I have been thinking toying with the idea of using tarps that drop/roll down from the ceiling to box in the table while in use. It won't change the amount of dust, but at least it won't go everywhere. Sorta like what this guy did... http://www.legacygarage.com/new_page_1.htm

[_Ogre]

we run our plasma water table in the same space with an automotive paint booth
while i try not to cut when the painter is painting, he's never complained about the dust

[chasxjs]

I also run a water table and do not have any dust issues. Occasionally a bit of smoke will escape but that is very minimal if I don't get lazy and let the water level drop too far.

[chrisj380]

Thanks guys for your ideas especially cap. The link you provided is a good cheap method to contain it for now. Another thought. Is there some kind of filter system that will help catch some of the dust if i don't do a water table?

[muzza]

You could look at either a reverse pulse filter system or a wet scrubber, neither of which are cheap. If you use a cyclone prior to either of these it will remove a lot of the solid particulate first to minimize running costs.
Murray

[Capstone]

The other idea I'm thinking about is using some kind of vacuum hose attached on the gantry right above the torch, sorta like a CNC wood router setup for sawdust.

[motoguy]

I'm interested in this, too. My plasma table is going to. E parked right next to my CNC mill. The thought of letting abrasive dust build up on the ways, or short out the control cabinet, freaks me out. I've been thinking of enclosing either the plasma table, or the mill, with a temp enclosure like the one linked above. Enclosing the table makes the most sense, as it will keep the rest of the garage clean, too.

[acourtjester]

I'm with Chasxjs a water table works very well I see it as capturing as much at the source as you can.
Blowing plasma dust outside is just messy remember if it lands on a surface like concrete or asphalt you will never get it all up and it will rust too.

[illusivedf]

My Dynatorch has a down draft table but never really had a fan to run it so my garage is filled with the fine dust everywhere. I hooked up a 12" duct to it with a 12" 2900 cfm blower on it and it seems to pull a good amount of smoke out while its cutting if the table is covered. They recommend a 3500cmf blower with 2" static pressure so mines little under. I found a 16" blower with a little under 3800cfm I am thinking about picking up with a 12"-16" adapter duct. The problem is even if it works I'm still just blowing the dust outside where it can end up rusting on vehicles and the garage.

I'm in the process of looking for a larger shop but I have an idea I plan to test as soon as I find something and get everything hooked back up because I do not have the extra room to build this now. Attaching a quick drawing of the idea.

Basically the air comes out of the downdraft table in a 12" duct which then goes into a sealed cabinet with a door on it that has a seal as well. At that point the duct turns down 90 degrees into a plastic storage tote bucket with a 12" hole cut into the lid for the duct and one for air to escape or could be a bunch of smaller like 2" holes as well. Once the nasty dust air enters the bucket it will go into water which would act as a filter maybe an inch or 2 over the duct so no air dirty air can escape. once filtered it would go up through the other 12" hole or multi small holes (multi small holes may keep the splashing down or just run a 12" straight up out of the lid, just to keep the mess down). At that point the "clean air" would exit via the blower which is mounted up higher to help keep from getting to much of the dirty water on it.

This way the bucket can be pulled out the door and emptied and fresh water added, maybe put some kind of wheel base under the bucket to make it easier. you could probably add a HVAC home or hepa filter or cartridge style powder coat filter on the blower as well if you get any fine blow by dust getting past the water.

This would help keep the heat in a shop in the winter as well. I have been wanting to build this for a couple years but I don't have the space for the cabinet right now.

[Shane Warnick]

I think the above illustration would work, with one exception. Pulling a vacuum through 2" of water is no small task, and doing it and moving a ton of air is a greater one. Not only is that a large area of water to lift / pull through, at the air volumes you want, it's gonna be a mess and splash water everywhere (stick your air nozzle in the bottom of a 5 gallon bucket of water and turn it on full blast,) until it's lower than the duct, and then inefficient. Might consider using some sort of screen / filters like the wet scrubbers do, make a grid with filters, and use a water pump from a swamp cooler to run water down through the cooler pads, and into a reservoir. Then you can just clean the pads and change the water, and the increased surface area will allow greater efficiency with air movement.

Shane

[WyoGreen]

Jim Colt described a system he uses at shows to confine the dust when doing demonstrations. Basically some fans and filters built into the table. You might do a search for it on PlasmaSpider, as that's probably where I saw it.

Steve