This is what I've done recently:
1. Got a 12V CPU fan from an old computer (older CPU, fan was smaller than some of the fans they sell at computer stores, but it churns out enough air).
2. I bought a variable transformer (one that allows you to set the voltage from 3-12V).
3. Stripped the connectors on the transforms and exposed maybe half an inch of wiring on the transformers, did the same on the fan.
4. Since you're dealing with 12V, there's no real danger of getting hurt, so just find which two wires start up the fan and then connect them using electrical tape. Make sure the wires can't cross! Crossed wires will spark and eventually catch fire.
Now, the neat thing about a variable transfomer is that you can set the voltage. Setting the voltage lower will slow down your fan (this is what the fan controller beener referred to does, but only for the single connected fan you're using).
Costs:
PC Fan, about $4-5.
Transformer, About $5-7.
Other ways... If you have an unused spare cell-phone recharger, check the output, if it's 12V, your fan will work full speed, if it's less, your fan should work, but slower.
These types of fans are mostly useful for moving air around the plants so they become stronger, not to cycle air around the room.
If you really want to cycle air around the room, the best thing is to use an electrical vent (is that the right name for it?). The good ones can be hooked to hoses which allows you to use a smaller drill area to move air around. Idealy you'd use two of these (one to get air in, one to get air out). But, even using one to get air out and just drilling a hole to get air in should work (causes negative air pressure to suck air in). |