What can I use to cut thick rope / marine rope (approx. 30 mm)?

Unless you are dealing with fine-fiber Kevlar® ropes, ropes and thick marine ropes can be cut with cable scissors (e.g. 95 12 200). The handy cutter for flexible hoses and plastic conduit pipes KNIPEX PlastiCut® 90 20 185 also work very well for ropes up to 25 mm in diameter.
Our tip: Wrap the rope with adhesive tape where you want to cut it to prevent it from fraying / untwisting.

9020185

90 20 185
KNIPEX PlastiCut®
Cutter for flexible hoses and plastic conduit pipes