Downdraft

[Jspece]

Still researching tables. Thinking a downdraft system is the way to go for fume/dust control. Few questions regarding this type system. Major concern for me is potentially blowing a spark outside into dead grass/leaves and having a fire. Is this a real concern or just me over thinking things? Also my shop is only 16x20 how much of my heat will I loose in the winter? I'm in Iowa

[icmplasma85]

Downdraft is definitely the way to go. I just took a 5 gallon bucket, filled with water and placed it directly under my 10" exhaust duct outside. My fan is 12" so from the back of the fan I ran 12" duct thru wall outside about a foot, 90 degrees down and capped with a 12" to 10" reducer that goes past the top edge of the bucket and down into it a few inches to make sure everything goes into the water. I recommend using a hard duct exhaust but the flex duct is great for the fan to table connection.

[K D Metalwerks]

I built a downdraft system for my PlasmaCam table. I have a 20", 6000 cfm exhaust fan on the side of upstairs sop wall. 18" duct tube connects that to a large box on attic floor above table. I connected 3 12" tubes from that box down thru floor and onto side panel of plasma table. I worked with the fan manufacturer to determine correct tubing size relating to cfm output of their fan. Works great! Due to the length of all the tubing, I do not have much concern of sparks blowing out of fan. Almost 30 feet from table to fan. have a switch close by so that I only use it when cutting as it does draw heat away.