Have you ever been driving through the desert of Las Vegas in the middle of summer, or the humid air of Florida in mid summer, or worse yet doing so to go out on a date or to a party just to get there and as you step out of your car, you realize that the back of your shirt is all sweaty and wet from the drive there? Nobody likes it when they got back swass (back and sweaty [butt] ). You dont like it, and especially the ladies hate it, so here is the the solution. The Back Swass Preventer!

Step 1: Tools and Parts

The price to build this only cost me $1 which was the back rest, the other parts and supplies came from around the house. Only a few simple tools and parts are needed and very minimal electrical knowledge is needed being that there is only 2 wires involved and you got a 50/50 shot of getting it right. haha.

Parts

The back rest $1 (bought from 99cent store)
Zip ties
Electrical tape
A couple computer fans
scrap wire and cigarette lighter plug in

Tools

Wire Strippers
Wire snips

The whole build from start to finish took me only 20 mins so its a very easy project.

Step 2: Fan Placement

The placement of fans on the back rest all depends on your preference and fan size. I had four fans to choose from. All these fans were salvaged from computer power supply's. I originally wanted to use just the one biggest fan but after turning it on and testing it, the bearing were really worn out in it and it was really loud blowing air. so I decided to use the two smaller fans that moved about the same amount of air and were so quiet that I couldnt hear them at all. These fans run on 12 volts and 0.14 amps and spin at 2300 RPMs which all of them say that so its a universal computer thing I guess. They are perfect for a direct 12 volt plug in.

I placed the two fans between the support part of the back rest that sits against the seat of the car and the mesh part that your back rests on. this spot is perfect because it allows the fans to cool the lower part of the back where swass occurs and the fans arent suffocating for air. To secure the fans to the mesh I just used a black zip ties and went thru the fan's screw holes on the corners and tightened them to the mesh. simple enough right? I tested it after I zip tied it by sitting on against it and I didnt really feel the zip ties.

Next step is to wire it up!

Step 3: Wiring

The simplest part of this build yet! For mine, I just took some scrap computer power supply cables and cut them off the power supply. They were perfect because for this because the cable had a molex type plug at the end to disconnect the back rest when not in use. I also scrapped a cigarette lighter plug from a power inverter I never use.

I took the 2 wire molex plug and matched wire color for wire color on the plug and fans. Black to black and red to red, then just taped up the wires with some electrical tape. As for the cigarette lighter side, I plugged in the molex plug and used the two wires the plug connected to which were yellow and black. With a little common sense there will be no issues here as long as you pay attention. wire color isnt an issue as long as you know whats what.

The cigarette lighter has two black wires so I ohm'd it out to see what wire is positive on the cord. the tip on a cigarette lighter plug is positive so just ohm out the two wires and see what wire is what. After finding this out I cut off the remaining two wires that werent used on the molex plug (red and of the black wires), then I taped the connections with electrical tape.

Now its all wired up, we can test it out before its taken out to the car.

Step 4: Testing and Finalizing

I used a 12 volt plug that went to a router to test my fans before going outside to plug it in. I grabbed two wires and connected up to the top of the lighter plug and they whirled to life blowing plenty of air. So the next step is to go outside plug' er in and see if it works in with your seats! It works perfect for mine. the fans have plenty of clearance and dont rub on anything. they are quiet and keep my back nice and cool.

If your fans dont turn on when you have it plugged in, you either didnt have the vehicles ignition on to where the lighter has power or you wired it wrong. Its ok, you had a 50/50 shot right? haha. theres no worrying needed, having it wired wrong poses no issues to the cars electrical systems or the fans themselves. Just switch the wires around and youre good to go! This only took me 20 mins to build and it was worth every second and $1 I spent. Enjoy!