From the Make Halloween Edition by Zack Stern
Step 1: What You Need...
2. Small diameter plastic or vinyl tubing
3. Baby medicine dropper or turkey baster
4. Hot glue
5. Dremel or grinder
Step 2: Prepare the knife...
Step 3: Make it...
WARNING: Be sure to wear safety goggles and gloves.
Then using a grinder or file, flatten out ALL of the blade edges and corners. Carefully test it with your finger to make sure it is not sharp. We don't want to draw real blood.
Using hot glue, secure the tubing to the blade. You may want to test the blade on your arm for the best location of the tubing so the 'blood' squirts out at the right spot.
Step 4: Use it...
This effect works best with long sleeves. Run the end of the tube up your sleeve and down your shirt or jacket. Suck up some blood using the medicine dropper or baster and attach it to the open end of the tube. Your hollywood effect is ready to use.
Lay the knife down on your arm and slowly squeeze out the blood as you make a spine-tingling scream!
I hope you enjoyed this Halloween SFX Instructable!