Blood spurting razor prop
Designer Peter England provided the design for the spurting blood razor prop used in the 1998 production of "Sweeney Todd". Using Peter's design, David Wilson devised the technical details required to achieve the desired effect and, after drafting DXF files of the blood razor parts, had them laser cut in aluminium. Small latex bladders were made which fitted into a cavity within the prop razor body.
Blood razor latex bladders
A detailed description on making the latex blood bladders used in the blood razor prop is an interesting read. The blood was expelled from the bladder by squeezing a clear acrylic lever in the handle which forced the blood from the internal bladder onto the blade. Two throats could be cut from one full bladder in the blood razor.