Your Weed Eater can convert to a brush cutter with the addition of a brush-cutting blade kit available at home improvement centers. The Poulan Weed Eater brand uses a full thread shaft below the gearbox that makes exchanging the stringer spool for a blade a quick process. Care needs to be taken when handling brush-cutting blades because they are very sharp and will cut skin with ease.
Unplug the spark plug wire from the spark plug with your fingers. Put leather work gloves on prior to removing the stringer spool and handling the brush-cutting blade.
Rotate the dust cup until the hole in the side of the dust cup lines up with the hole on the gearbox. The dust cup is the portion between the top of the spool and the bottom of the gearbox. Insert a flat-head screwdriver through the hole in the dust cup and gearbox. This will lock the shaft while you exchange cutting heads.
Turn the string spool counterclockwise with your hand to remove the spool from the threaded shaft. Pull the retaining washer off the shaft but leave the dust cup in place.
Install the brush-cutting blade over the shaft and place the retaining washer over the blade.
Slide the blade cup washer over the retaining washer. The blade cup washer looks like a washer with a slight concave. The concave portion of the washer should point toward the blade.
Secure the blade assembly with the blade retaining nut and tighten the nut with a wrench. Take the screwdriver out of the duct cup and plug the spark plug wire over the spark plug.