Ratchet Lug Crimper — 6-16mm² for Uninsulated Copper Lugs

Q: What does a ratchet crimper actually do?
The ratchet holds the lug under pressure every time you squeeze until the die fully closes. You can't let go partway through, which is what gives repeatable crimps vs a plain plier crimp.

Q: When should I pick this over the hex 6-50mm² or the hydraulic 6-70mm² crimper?
This covers 6, 10 and 16mm² lugs for most 4WD auxiliary wiring, fuse holder leads and bus bar feeds. Step up to the [crimping-tool-copper-cable-lugs-hex-6-50mm2] for 25, 35 and 50mm² alternator mains and inverter leads. The [hydrualic-lug-crimper-up-to-70mm2] handles 70mm² for the biggest DC runs and winch feeds.

Q: Does it crimp aluminium or lead lugs?
No. Hex and ratchet dies are shaped for copper's flow pattern. Aluminium needs a controlled hex compression on a hydraulic tool with aluminium-specific dies, and lead is too soft to hold a mechanical crimp.

Q: Does it work on insulated terminals?
No. Insulated terminals need a plier-style crimper with a tongue-and-roll die that compresses the metal barrel inside the plastic sleeve without cracking the plastic.

Q: How do I know the crimp is finished?
Keep squeezing to the audible ratchet release click. If the handles stop short of click, the die isn't fully closed and the crimp hasn't formed. If the lug tilts in the jaw, hit the release lever, re-seat it square and start again.

Q: Which die position do I use for which lug?
Match the die cavity number to the lug's cable rating on its stamp. 6mm² lug sits in the 6mm² cavity, 10mm² in the 10, 16mm² in the 16. Using a bigger cavity than the lug under-crimps and the lug slides off the cable.

Q: Does the handle leverage mean I can do it one-handed?
On 6 and 10mm² lugs, yes, with a firm hand. On 16mm² you'll want two hands or your body weight on one handle while bracing the other. Short-handled crimpers in this range need two hands throughout.

Q: Can I crimp heat-shrink lugs with this?
Yes. Crimp the lug the normal way, then warm the heat-shrink section with a heat gun while the barrel is still warm from the crimp. The dual-wall adhesive-lined type seals best this way.

Q: Do the dies wear out?
The hex dies are built into the jaw and last thousands of crimps on 6-16mm² copper before the hex corners round over. If the dies start leaving a round crimp instead of a clean hex, step up to a hydraulic tool with replaceable dies.

Q: What size lug for my cable?
Match the lug's cable rating stamp to the cable gauge in mm². A 10mm² cable goes in a 10mm² lug. See our [cable-lug-to-copper-stud] range for selection by cable size and stud diameter.