pdillo
Well-Known Member
So I made this ghetto 4 inch inline fan for about 15 bucks. I used a 120mm 133cfm Ultra Kaze computer fan, which also has decent static pressure
for a computer fan. On the intake side I used a dryer blocker, I took out the blocker and hacked one of the sides off. On the out-take side I used a 5" to 4" reducer, (5 inches is just a little bigger than 120mm). I foil taped the reducer from the inside to a 6" drain frame after drilling some holes in. It's not a perfect fit
but it works pretty well. The reason one side is tapered and the other is not is because I noticed most inline fans don't taper on the intake side because no drag is created by NOT having a taper
which of course isnt the case for the exhaust.
You could probably do something nicer with a piece of masonite and 5" hole saw. After that I just put some 120mm gaskets on the fan, and screwed everything together with some 2" screws.
I've attached this about 5 inches away from my bake-around with a 400w hps, just to test it out, sat it on the stove and ran it for about 30 min. Got pretty damn hot around the light, but the ends of the cooltube kept cool to the touch. However there was no ducting attached to the end of the fan or the other end of the cool tube, so some more static pressure will be added to the load when I really put it to use. I just hope the thing doesnt melt I want to run the fan right next to the light to keep the air moving fastest next to the bulb, I read that somewhere. I think it will stay cool enough to be pretty safe. If it doesnt work, I'll use the fan for something else and cough up the money for a real duct fan.
You could probably do something nicer with a piece of masonite and 5" hole saw. After that I just put some 120mm gaskets on the fan, and screwed everything together with some 2" screws.
I've attached this about 5 inches away from my bake-around with a 400w hps, just to test it out, sat it on the stove and ran it for about 30 min. Got pretty damn hot around the light, but the ends of the cooltube kept cool to the touch. However there was no ducting attached to the end of the fan or the other end of the cool tube, so some more static pressure will be added to the load when I really put it to use. I just hope the thing doesnt melt I want to run the fan right next to the light to keep the air moving fastest next to the bulb, I read that somewhere. I think it will stay cool enough to be pretty safe. If it doesnt work, I'll use the fan for something else and cough up the money for a real duct fan.
