All sewing produces lint, so having one of these lint brushes handy is a must!  The nice thing about this style is that one end is used for lint and the other end is used for cleaning gears of old grease build-up. 

Make sure!!  When you remove your Featherweight to clean out the lint that you replace it with the positioning finger on the bobbin case base in the correct place.  The positioning finger needs to be between the disks on the underside of the throat plate.  A2 needs to be in the B2 slot as shown in the illustration below.