milrtyme24 Posted August 16, 2011 Report Share Posted August 16, 2011 Ive read most posts about using a stove hood to vent the plastic fumes outside of your work area. My question is do you guys put in different fan to exhaust the vents. Ive tried to find how many cfm mine is but I can find it. The hood is about 10 years old, it came of my hood when i replaced it with a stainless steel type hood. Im not very good with electrical stuff but running the vent and putting up the hood will be no problem. Right now I use about a gallon of plastic every 2 weeks and Im not airbrushing yet but would like to in the future. So do i need to replace the fan and if so what type of fan and where do I find it? As always thanks for any input. Quote Link to comment Share on other sites More sharing options...
GB GONE Posted August 16, 2011 Report Share Posted August 16, 2011 Try this for a rough gauge: This method works on the assumption that the goal for room ventilation is 8 complete air changes per hour. Take your square footage x ceiling height to get the total cubic feet to be ventilated. Example: Room measures 10 feet wide and 12 feet long. It has 8 foot ceilings. So 10 x 12 x 8 = 960 cubic feet. We take the cubic feet and divide by 60 - which is the number of minutes in an hour. We take the result and multiply by 8 (remember, our target is 8 complete air changes each hour). The complete equation is as follows: STEP 1 10 ft X 12 ft X 8 ft = 960 cubic feet. STEP 2 960 divided by 60 = 16. STEP 3 16 x 8 = 128 So - we need 128 CFM of air movement to properly ventilate this room. Assuming there is not and excessively long or twisting duct run to the outside - we would select a fan that moves somewhere around 130 CFM or higher. Home Depot, Lowe's or garage sales for larger fans.... Jim Quote Link to comment Share on other sites More sharing options...
powerworm Posted August 16, 2011 Report Share Posted August 16, 2011 or for laboratory type installations which this is closer to you would take your existing hood and measure the dimensions of it lets go with 2'x3' which gives you 6 square feet of area multiply that by 100 cfm per square foot of hood area and you come up with 600cfm as a minimum to adequately keep the fumes exhausted; and even then if you can walk in the room and smell the plastisol you dont have enough ventilation always think bigger not smaller in this case 1 Quote Link to comment Share on other sites More sharing options...
GB GONE Posted August 16, 2011 Report Share Posted August 16, 2011 True Jon. My example suggestes room air exchanges 8 times per hour only. Probably not enough for plastisol fumes. Also consider if you are pouring directly under the hood, your air exchange will be greatly increased. Jim Quote Link to comment Share on other sites More sharing options...
Musky Glenn Posted August 16, 2011 Report Share Posted August 16, 2011 PowerWorm- I don't completely understand your example. Since your example doesn't use the size of the room, it seems to me that the 600 is a MAXIMUM that the hood can vent instead of a minimum. If you use the figures of ghostbaits where he said he needed 128 cubic feet per minute, then this vent should be more than enough. This is why I don't understand, please set me straight. Musky Glenn Quote Link to comment Share on other sites More sharing options...
Kajan Posted August 17, 2011 Report Share Posted August 17, 2011 PowerWorm- I don't completely understand your example. Since your example doesn't use the size of the room, it seems to me that the 600 is a MAXIMUM that the hood can vent instead of a minimum. If you use the figures of ghostbaits where he said he needed 128 cubic feet per minute, then this vent should be more than enough. This is why I don't understand, please set me straight. Musky Glenn If you use a hood to remove fumes in the area of your pour station, and say your hood is 4'X3' horizontal measurments. You would need a fan with 1200 CFM 0 static pressure to have enough suction to remove fumes safely. You might be able to get away with 1000 or you can go up to 1500 CFM's. and if you put sides on your hood you could probably get away with 1000. Now 1200 cfm fan will be 16" dia. minimum unless its high velocity fan, but you won't be able to stand the noise from one of those. Quote Link to comment Share on other sites More sharing options...
Pitbull Baits Posted August 17, 2011 Report Share Posted August 17, 2011 If you use a hood to remove fumes in the area of your pour station, and say your hood is 4'X3' horizontal measurments. You would need a fan with 1200 CFM 0 static pressure to have enough suction to remove fumes safely. You might be able to get away with 1000 or you can go up to 1500 CFM's. and if you put sides on your hood you could probably get away with 1000. Now 1200 cfm fan will be 16" dia. minimum unless its high velocity fan, but you won't be able to stand the noise from one of those. Ya forgot fresh air supply K. If ya want to suck air out you need to bring fresh air in. A $30 range hood should work fine. You may need to get a 3 1/4" X 10" register boot so you can round pipe it out. Then you can get 4 inch to 6 inch round pipe. Its a lot cheaper then buying 31/4 X 10 duct, 45 degree ells and 90 degree ells. CFM"S for a Broan/ Nu tone Range hoods range from 250 cfms to 600 cfms. They do go higher but your talking some big time cash for that then. I just use a box fan in front of my window. I also have a shop and my pouring station is right in front of the window for that reason. I set it on low and it sucks it all out. Mind you its 10 inch"s from the window.Depending o0n your height from the fan I wouldn't go over 300 cfms. *That's just my opinion* (Disclaimer) Kajan is a fellow sheet metal guy Quote Link to comment Share on other sites More sharing options...
powerworm Posted August 17, 2011 Report Share Posted August 17, 2011 thanks for setting them straight Kajun; we all know how well the range hoods in our kitchens work as soon as you walk in the house you know whats cooking but with adequate ventilation you wont smell a thing just fresh air Quote Link to comment Share on other sites More sharing options...
Kajan Posted August 17, 2011 Report Share Posted August 17, 2011 Ya forgot fresh air supply K. If ya want to suck air out you need to bring fresh air in. A $30 range hood should work fine. You may need to get a 3 1/4" X 10" register boot so you can round pipe it out. Then you can get 4 inch to 6 inch round pipe. Its a lot cheaper then buying 31/4 X 10 duct, 45 degree ells and 90 degree ells. CFM"S for a Broan/ Nu tone Range hoods range from 250 cfms to 600 cfms. They do go higher but your talking some big time cash for that then. I just use a box fan in front of my window. I also have a shop and my pouring station is right in front of the window for that reason. I set it on low and it sucks it all out. Mind you its 10 inch"s from the window.Depending o0n your height from the fan I wouldn't go over 300 cfms. *That's just my opinion* (Disclaimer) Kajan is a fellow sheet metal guy Ma' I did'nt forget nothin PB , he needs to understand one part before moving on to the next. Quote Link to comment Share on other sites More sharing options...
milrtyme24 Posted August 17, 2011 Author Report Share Posted August 17, 2011 Ya forgot fresh air supply K. If ya want to suck air out you need to bring fresh air in. A $30 range hood should work fine. You may need to get a 3 1/4" X 10" register boot so you can round pipe it out. Then you can get 4 inch to 6 inch round pipe. Its a lot cheaper then buying 31/4 X 10 duct, 45 degree ells and 90 degree ells. CFM"S for a Broan/ Nu tone Range hoods range from 250 cfms to 600 cfms. They do go higher but your talking some big time cash for that then. I just use a box fan in front of my window. I also have a shop and my pouring station is right in front of the window for that reason. I set it on low and it sucks it all out. Mind you its 10 inch"s from the window.Depending o0n your height from the fan I wouldn't go over 300 cfms. *That's just my opinion* (Disclaimer) Kajan is a fellow sheet metal guy Thanks guys, I work in my basement which is also a 2 car drive in under the house type deal. But the area I work in is about 16 x 12, no windows but 2 big garage doors that i open plus have a window fan blowing it out right now, but this winter Im going to have to vent the fumes outside. I have the range hood I can build what ever else I need. I was just wanting some ideas about the fan, I like pitbulls idea thats kinda what I had in mind but I like all the info and I appreciate all of your input. Im planning om buying me a building like you get at lowes or home depot or I might build one but not in the budget right now. Quote Link to comment Share on other sites More sharing options...
Pitbull Baits Posted August 17, 2011 Report Share Posted August 17, 2011 If you get a range hood just make sure its the ones you can vent outside. Some of them just pull the air through a filter of sorts on the bottom and blow the air out the front of it. That is the ones PW is talking about. You can get some flex type piping for cheap and run it right out the bottom of the garage door. Then block off the other open area on the bottom with something. During the winter I block my double doors in me shop with blue tarps and duct tape it the frame. You could do something like that but just for the bottom area of the door. Quote Link to comment Share on other sites More sharing options...
milrtyme24 Posted August 17, 2011 Author Report Share Posted August 17, 2011 Thanks guys, I work in my basement which is also a 2 car drive in under the house type deal. But the area I work in is about 16 x 12, no windows but 2 big garage doors that i open plus have a window fan blowing it out right now, but this winter Im going to have to vent the fumes outside. I have the range hood I can build what ever else I need. I was just wanting some ideas about the fan, I like pitbulls idea thats kinda what I had in mind but I like all the info and I appreciate all of your input. Im planning om buying me a building like you get at lowes or home depot or I might build one but not in the budget right now. Sorry to double post, but a little more info. My kids are off to college, my wife works during the day so I only pour during the day but I have a couple if inside dogs and I do not want to kill my dogs just because of my addicting hobby . I have been pouring about 2 months with the garage doors open a fan going and I wear a mask. I became concerned when I read all the posts about plastic fumes. With my current setup all of the fumes are probabaly not going outside but Im guessing most are but I want to be sure. My work area is about 12 x 16 and close to the garage doors but I definitely need a plan for the upcoming winter. I have had no health concerns and the dogs have not yet. The whole basement area is about 34' wide by 38' long. I have the drive- in basement thats mostly underground and then a 2 story house setting on top of the basement . Again thanks all the input. Milrtyme Quote Link to comment Share on other sites More sharing options...
Pitbull Baits Posted August 17, 2011 Report Share Posted August 17, 2011 I have a 30'X40' building I work out of. I think I know the style of house you are talking about. If you can just work closer to the doors. You could put up and range hood and the vent it out but you would have to pop a hole through the wall. You could just make it look like a dryer vent coming out the side of your house. You would have a flapper on it so the cold doesn't come back in. You have a wide range of things you could do for venting in the space you got. 1 Quote Link to comment Share on other sites More sharing options...
Smallie Posted August 18, 2011 Report Share Posted August 18, 2011 If you use a hood to remove fumes in the area of your pour station, and say your hood is 4'X3' horizontal measurments. You would need a fan with 1200 CFM 0 static pressure to have enough suction to remove fumes safely. You might be able to get away with 1000 or you can go up to 1500 CFM's. and if you put sides on your hood you could probably get away with 1000. Now 1200 cfm fan will be 16" dia. minimum unless its high velocity fan, but you won't be able to stand the noise from one of those. This is pretty close to my set up. I removed a window, close the opening with plywood and put a gable end fan from Home Depot in the plywood. I never smell a thing and when I am pouring, any smoke coming off the plastic moves towards the fan immediately. There is an arborvitae growing in front of the area and it does not show any discoloration even though I can see the fan moving the foliage. Quote Link to comment Share on other sites More sharing options...
Musky Glenn Posted August 18, 2011 Report Share Posted August 18, 2011 (edited) I feel so thick headed about this air circulation, I don't know what it is I am not understanding. (This room only has 960 cubic feet of air in it. If you use a fan that moves 1000 cfm, then the air is being completely changed every minute. That would be so much turbulance you wouldn't be able to hand pour plastic, much less keep any heat in the room. A lot of the residential hood vents are rated at 300 cfm which should change the air out in 4 minutes or 15 times per hour. Am I completely missing something on this. Just trying to understand. Musky Glenn Edited August 18, 2011 by Musky Glenn Quote Link to comment Share on other sites More sharing options...
Pitbull Baits Posted August 18, 2011 Report Share Posted August 18, 2011 I feel so thick headed about this air circulation, I don't know what it is I am not understanding. (This room only has 960 cubic feet of air in it. If you use a fan that moves 1000 cfm, then the air is being completely changed every minute. That would be so much turbulance you wouldn't be able to hand pour plastic, much less keep any heat in the room. A lot of the residential hood vents are rated at 300 cfm which should change the air out in 4 minutes or 15 times per hour. Am I completely missing something on this. Just trying to understand. Musky Glenn You would be good with a 300 cfm hood. 1,000 cfm are for kitchens when you are running fryers, grills ovens and so on. A range hood in your house is no more then 600 cfm 9 out of 10 times. Your only trying to pull the air around the stove top area out. if you get into 1,000 cfm hoods you would have to bring in make up air (fresh air). Otherwise your not going to pull 1,000 plus cfm's. Everyone seems to think the more power you got the better it is. That's not the case for the small area's we are trying to cover. If you want a brand new 4'x8' stainless steel kitchen hood with a 1,200 to 1,500 cfm exhaust fan, built in fire extinguishers, Safety shut off panel, grease traps and lights in it I got one at my work for around $3,000 plus shipping. You will need a make up air unit with a heater built in it. We just didn't use it on a job and are stuck with it. Quote Link to comment Share on other sites More sharing options...
Musky Glenn Posted August 18, 2011 Report Share Posted August 18, 2011 Thanks Pitbull. Musky Glenn Quote Link to comment Share on other sites More sharing options...
Kajan Posted August 18, 2011 Report Share Posted August 18, 2011 I'm not gona argue, but PB your wrong Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted August 18, 2011 Report Share Posted August 18, 2011 (edited) It is all about the air velocity at the pot, where the fumes are generated and nothing to do with the size of the room. I have an axial fan fitted in my workshop door. On the blow side, it will blow your socks off, but on the suck side, I can stand three feet away and smoke will hardly deflect towards the fan. The problem is that the fan is drawing air from all directions, so to generate the required airflow, say 1 foot per second, is going to require a powerful fan. But, if you reduce the size of the hood and mount it as close to the pot as possible, then you can achieve the required airflow with a very small fan. With a bit of thought and ingenuity, a standard range hood fan can be made to work for you. Dave Edited August 18, 2011 by Vodkaman Quote Link to comment Share on other sites More sharing options...
powerworm Posted August 18, 2011 Report Share Posted August 18, 2011 If you get a range hood just make sure its the ones you can vent outside. Some of them just pull the air through a filter of sorts on the bottom and blow the air out the front of it. That is the ones PW is talking about. You can get some flex type piping for cheap and run it right out the bottom of the garage door. Then block off the other open area on the bottom with something. During the winter I block my double doors in me shop with blue tarps and duct tape it the frame. You could do something like that but just for the bottom area of the door. uh...no that is not the type i am talking about??? any of the home project stores sell range hoods and unless you order one with a MUCH larger fan you wont even be able to remove the smell let alone any carcinogens. but i do like your idea of a box fan i just am partial to my range hood with sides that i took the motor out of and cut a 12" circle in the top and vented it with an adequate exhaust fan. it has about an 18" run at a 45 degree angle upwards to a louver panel. it works good enough that you can walk in my garage and not even smell the plastic cooking Quote Link to comment Share on other sites More sharing options...
milrtyme24 Posted August 18, 2011 Author Report Share Posted August 18, 2011 You would be good with a 300 cfm hood. 1,000 cfm are for kitchens when you are running fryers, grills ovens and so on. A range hood in your house is no more then 600 cfm 9 out of 10 times. Your only trying to pull the air around the stove top area out. if you get into 1,000 cfm hoods you would have to bring in make up air (fresh air). Otherwise your not going to pull 1,000 plus cfm's. Everyone seems to think the more power you got the better it is. That's not the case for the small area's we are trying to cover. If you want a brand new 4'x8' stainless steel kitchen hood with a 1,200 to 1,500 cfm exhaust fan, built in fire extinguishers, Safety shut off panel, grease traps and lights in it I got one at my work for around $3,000 plus shipping. You will need a make up air unit with a heater built in it. We just didn't use it on a job and are stuck with it. Well bad news about my hood vent, its got a fan but its the type that just sucks the air up and blows it out of a vent in the front. So now im really open for suggestions, sorry pitbull but $3,000 is a little out of my range.....Thanks anyway. Could I cut a hole in top of the hood vent, put in a new fan and run a vent outside , would that work? If so sorry to ask again but is there a website besides ebay that I can order a fan? eBay is ok but sometimes you really dont know what you get until it arrives. And again Im wanting to get by as cheap as I can (who isnt) so any suggestions are welcome and very much appreciated. Milrtyme Quote Link to comment Share on other sites More sharing options...
Pitbull Baits Posted August 19, 2011 Report Share Posted August 19, 2011 I seen ones that vent out the back at all the big box hardware stores. They started out at around $29.95. I wouldn't try and alter it could be a hazard waiting to happen. Quote Link to comment Share on other sites More sharing options...
powerworm Posted August 19, 2011 Report Share Posted August 19, 2011 Well bad news about my hood vent, its got a fan but its the type that just sucks the air up and blows it out of a vent in the front. So now im really open for suggestions, sorry pitbull but $3,000 is a little out of my range.....Thanks anyway. Could I cut a hole in top of the hood vent, put in a new fan and run a vent outside , would that work? If so sorry to ask again but is there a website besides ebay that I can order a fan? eBay is ok but sometimes you really dont know what you get until it arrives. And again Im wanting to get by as cheap as I can (who isnt) so any suggestions are welcome and very much appreciated. Milrtyme do you have a lowes or home depot close by lots of things can be special ordered either in store or online Quote Link to comment Share on other sites More sharing options...
GB GONE Posted August 19, 2011 Report Share Posted August 19, 2011 Check flea markets and garage sales or get ahold of guys that remodel in your area. They usually throw the kitchen exhaust stuff out and might be glad for you to take it. I bought my "old" one at a garage sale for $15. As long as you can live with the olive green color, you are good! Jim Quote Link to comment Share on other sites More sharing options...
GB GONE Posted August 19, 2011 Report Share Posted August 19, 2011 Also, try www.searsoutlet.com... They have some for $15 if you have one in your area.... Jim Quote Link to comment Share on other sites More sharing options...
