The production team from the TV show The Walking Dead goes through buckets and buckets of blood. So much blood. Of course, it’s all fake blood, and it comes in many different types. Property master John Sanders explains the many different types of blood the show uses. There are different colors for the zombie blood, depending on how rotten they are, different viscosities for the specific ways blood is used in a scene, and some workarounds, too, because shooting blood on film is different from real life.
If a weapon has to remain bloodied for more than one scene, they'll usually paint onto a plastic or rubber version of the prop weapon. This way the team won't have to worry about permanently staining the weapon, as the alcohol based blood is easier to wash off. This trick is especially handy because one scene may take multiple days to film, and constantly re-staining with prop blood may damage the weapon.
"We have a number of alcohol based paints that we’ll paint on there because they may have to match that for a whole scene," Sanders explained. "That weapon’s supposed to be bloody for the next 10 scenes of the show, but those 10 scenes may be over eight days. We have a lot of tricks."