Knex Alarm By knex gun and grenade maker in LivingLEGO & K'NEX1,2513Save PDFFavoriteIntroduction: Knex AlarmBy knex gun and grenade makerFollowMore by the author: this is a knex fire alarm that is VERY simple to make. Step 1: Makein makeStep 2: OTHER... SEARCH ALARM VIDEO AND WATCH THE VIDEO.