Blades are consumables. Cutting into copper or stone, or simply cutting PVC day after day, dulls the edge. A dull blade needs more grip force and damages conductors more easily—if stripping feels heavy or the cut looks white, replace the blade.
After each use, blow out cuttings near the blade and wipe off PVC plasticiser residue. Add one drop of light oil to the pivot—avoid solvent sprays. For long storage, release the spring and keep the tool dry.
JOKARI offers genuine replacement blades, cassettes, brackets and ferrules. Confirm the article number and tool model before ordering so you get the right cassette.