The purpose of the pocket-sized fume extractor is to remove all harmful fumes from the air that are created by smoldering solder. The fume extractor was built using very few parts and simply gets its job done wherever and whenever you need it without requiring an electrical outlet or large amount of space.
The fume extractor uses a 9v battery to power small 12v fan i purchased from Radioshack and contains only two soldered connections, and so it is an excellent project for anyone who is just learning to solder. Instead of containing an on/off switch, i built the extractor so that the battery is plugged into its body in order to turn it on while also acting as a stand for the extractor itself.
How does it work? The small fan sucks air containing fumes through it, and then blows them through a carbon filter that is glued in place in front of it. This effectively removes all dangerous chemicals that the fumes contain from the air around you as you solder, thus saving you from a headache as you work.
Step 1: Gathering the Parts and Tools
For this project you will need the following parts:
-9v Battery (any brand)
-Hard plastic 9v battery clip
-Small hinged acrylic case (mine was bought with shark teeth in it, it's 55mm by 44mm by 20mm)
-12VDC Micro Fan (http://www.radioshack.com/product/index.jsp?productId=2102824&filterName=Brand&filterValue=RadioShack#tabsetBasic )
-Weller WSA350F Carbon Filters
-Red and black heat shrink tubing (optional; covers your solder connections)
You will also need the following tools/items:
-Soldering iron and Solder
-Fine point Sharpie
-Sandpaper (i used 80 grit)
-Heat gun (if using heat shrink tubing)
Step 2: Mark Before You Cut
Once you have gathered all of the necessary tools and supplies, lay your fan on/in your case so that it is touching its top and trace its outline onto the case using a Sharpie. Make sure to align the fan as close to the top of the case as you possibly can in order to leave plenty of room for the battery snap and battery.
After tracing the fan onto the the case on both its the front and back cut out two holes in the case along the lines you have created using your Dremel. These holes will serve as the air intake and outflow ports for the fan, and both the fan and carbon filter will be sandwiched in between them. Once you Dremel out your holes, make sure to sand the edges down and remove all plastic debris from the case.
Next, mark the width of your 9v battery on the bottom of the case and make sure you try to center where the battery will fit into the case. I did not need to mark the length of the battery on my case because its width was the width of the case which i used, and so i simply cut along the two lines i had created for the battery's width and along the edges of the container in between the two lines. When you're done cutting out the battery hole, your battery should be able to snugly fit into the case right way up when pushed through it. A snug fit ensures that the battery will act as a stable base. Lastly, sand the edges of the hole and remove any plastic debris that you may have created.
On an important side note [READ ME] ; make sure to check that your cuts will fit the fan in the case with a slight overlap on each side so that the bottom of the fan may be glued to the back of the case and allow plenty of room for airflow. You don't have to be as careful with size when cutting the hole on the side that the fan isn't glued to, because you can cut your carbon filter to fit that hole no matter how it turns out. I also laid things out after each hole was made to make sure everything fit snugly
Step 3: Soldering and Glueing
After you have cut out all necessary holes in your case, it is time to solder the fan to the battery! Cut and strip your wires for both the fan and battery clip so that they are short enough to fit in the case without excess wire hanging out. Then solder the red (+) wire of the fan to the red (+) wire of the battery clip, and solder the black (-) wire of the fan to the black (-) wire of the battery clip. If you choose to, you may also cover each connection using heat shrink tubing to prevent any short circuits.
Once you are done soldering, determine which way your fan blows air by looking for a small arrow icon on its side or by plugging in a battery to power the fan. Next, glue the fan by its four corners to one of the two large holes you cut in the case so that it blows air out the other large hole. This way, the fan can suck air into the case and blow it through the carbon filter and out.
After the fan is firmly glued in place, attach a 9v battery to the snap and put a dab of super glue on the top of the snap. Make sure to have the battery pushed through its hole in the case, and push the top of the snap onto the side of the fan so that it is glued in place. The reason why you should glue the snap in place while the battery is attached to it is so that the snap is positioned correctly on the fan. If you glue on the snap without using the battery as a guide, you may not be able to connect the battery to it through the battery's hole on the case. Wait for the glue to dry, and then remove the battery.
Step 4: The Carbon Filter / Finishing Up
The final step in the creation of the fume extractor is to attach the carbon filter to the fan. First, cut the filter so that it is the same size as the fan. Next, apply glue to the four corners of the fan and press the filter firmly into place. Your pocket-sized fume extractor is now complete! Plug in a battery and try it out, just make sure to unplug it when you're done.
Step 5: The Final Product
In order to keep things extremely simple and take up less space, i chose not to add an on/off switch to the circuit for the fan. If you choose to, you could easily attach a SPST switch between the red [positive] wires of the fan and battery clip. I would love to see pictures from anyone who chooses to build one of these, and feel free to ask any questions that you may have. Constructive criticism is welcome too!