CVD wiresaw concrete support at the National Gallery's Playfair Project in Edinburgh.
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The wire is positioned over the pulleys and fed through pre-drilled holes in the concrete that is being cut and back over the drive pulley. The wire can be of almost any length and is joined by special crimps.
Sawing is carried out by at a constant speed, whilst applying pressure on the wire by gently applying a steady backward movement by expanding the pulleys. Like a cheesewire.