A handsome looking junkbot with a fuel filter body.

Step 1: Parts and Tools:

Parts:
One Fram G8219 fuel filter (or similar looking fuel filter) ($8 at Walmart).
Two shower sliding door rollers ($2 at Home Depot, door handle and hinge aisle).
Two spring nuts ($4 for a box of five at Home Depot, metal conduit aisle).
Two springs (from a $4 box of 84 assorted springs from Home Depot).
Four #8 x 1/2 inch sheet metal screws ($1 at Home Depot).
Two #8 x 3/4 inch sheet metal screws ($1 at Home Depot).
Two 1/8 inch by 1 inch fender washers ($1 for a pack of 8 at Home Depot).
One bronze colored sawtooth picture hanger ($3 for a pack of three at Home Depot).
Two bronze colored "18-10" crimp sleeves ($3 for a box of 12 at Home Depot, audio/video aisle).
Two spade terminals ($2 for a box of 15 at Home Depot, audio/video aisle).

Tools:
Phillips screwdriver.
1/8 inch metal drill bit.
Dremel with cutting wheel (preferred) or hacksaw.
Metal epoxy (preferred) or hot glue.
Goof Off or paint thinner.

Step 2: Prep the Body for Legs:

Cut off the spout on the bottom of the fuel filter with a hacksaw or Dremel. Then drill two 1/8 inch holes for the legs. Don't worry about drilling into the fuel filter, it contains only paper (the filter) and a little metal. Offsetting the holes so that they are not exactly next to each other with respect to the front of the robot should make it easier to balance him.

Step 3: Add the Legs:

Attach the spring nuts (legs) using the 1/2 inch sheet metal screws and washers. #8 sheet metal screws fit perfectly into 1/8 inch holes.

The spring nuts have holes in the bottom part (the feet) through which you can insert a screwdriver for easy access to the screw heads. It will take a few tries to make the bot balanced. Just keep adjusting them until it's balanced. The springs make a good bobblehead effect.

Step 4: Add Arms and Ears:

Drill two 1/8 inch holes on each side of the robot body, two holes for the arms and two holes for the ears. Your drill bit will wander a lot on the smooth, curved surface of the fuel filter, so first make a tiny notch in the metal using a Dremel cut off wheel or grinder. Start the drill bit in the notch and it will stay put.

The arms are made of springs with a terminal in one end. Use epoxy or hot glue to secure the terminal hand in the spring arm. These springs had bent ends. Snip off one bent end and use the other to screw the spring to the body using #8 1/2 inch sheet metal screws.

The ears are crimp sleeves held against the body with a #8 3/4 inch sheet metal screw.

Step 5: Add Eyes and a Mouth:

Cut the ends off the sawtooth picture hanger with tin snips or a Dremel. Bend it match the curve of the fuel filter body. The metal is thin so you can just set it on the fuel filter and push on it. Use epoxy to attach it to the body as a mouth, and the door rollers to the body as eyes.

Step 6: Finishing Touches:

The back of the fuel filter has some text that comes off with Goof Off or paint thinner. I keep some of the text because it seems robotic. Mask any text you want to keep and wipe off the rest.

The back has a lot of free space -- add some decals, a jet pack, other junk robot parts, or an ominous message about the upcoming filter bot invasion.

Step 7: Time for a Robot Dance Party:

There are lots of different things you can use for the body parts. Some paint might do wonders too. Or make one hold a sign. See what works and share pics of your own filter bots!