I'm not beind rude. What do you cut cardboard boxes with. Both words are in the answer "Box Cutters" I can say whatever i waant. And i didn't say something like "Box CUTTERS DUMASS" Calm down a little. We're cool
Whether for reinforcement or the armour id say box cutter would be best. It easily cuts boxes, it is what they made it for. If anyone has ever cut something like vegetables you know the sharper the object the easier it cuts and therefor the more precise you will be. So buy a new and sharp box cutter. An X-acto knife would probably work but you risk messing the cardboard up since you don't have quite as much control over it as you do a box cutter.