You’re Crimping Wires Wrong… Do This Instead!

Most hobbyists are crimping wires the hard way—and sometimes the wrong way. Those old $10 combo stripper/crimper pliers can turn your wiring harness into a future fire hazard by making weak, inconsistent crimps that invite corrosion, heat, and intermittent electrical gremlins. The good news? You can fix this easily with the right tool and a better method

Link to the things in this video 

Basic crimpers – https://amzn.to/44WR2L7

Ratchet Crimpers – https://amzn.to/3ML9tfw 

Terminal kit – https://amzn.to/48rg0Vf

Bulk wire – https://amzn.to/3KuQwgB

Why Cheap Crimpers Cause Problems

Basic stamped crimpers only squeeze the connector in one small spot. That point load can:

• Crush wire strands instead of forming them into a tight bundle
• Leave gaps where air and moisture can creep in
• Create higher resistance, heat, and eventual failure

Even if the wire “passes” a quick tug test, that doesn’t mean it’s durable or well sealed.

The Case for Ratcheting Wire Crimpers

Ratcheting crimpers have dropped in price and are now well within reach for DIY mechanics and weekend fabricators. For around $50, you can get a kit with:

• A ratcheting handle that applies consistent pressure every time
• Fixed or interchangeable dies for insulated, non-insulated, and specialty terminals
• Full support around the terminal barrel so it deforms evenly instead of folding or collapsing

The result is a gas-tight mechanical connection: the strands are compressed uniformly, air gaps are minimized, and pull strength is dramatically higher than with old-school pliers.

How to Crimp Wires the Right Way

1. Strip the wire correctly
   Use a sharp stripper sized to the gauge you’re working with. Avoid nicking or cutting strands.
2. Prep the wire
   Twist the strands gently to keep them together. Avoid excessive handling so you’re not loading skin oils and contaminants into the joint.
3. Match the terminal and die
• Non-insulated terminals: use the non-insulated die and follow the terminal seam/orientation recommended by the crimper maker.
• Insulated “red/blue/yellow” terminals: use the insulated die sized to the color/gauge.
4. Let the ratchet do its job
   Insert the terminal in the die first, start the ratchet so it holds the terminal, then insert the wire fully. Squeeze until the ratchet releases—don’t stop halfway.
5. Inspect the crimp
   You’re looking for:
• Smooth, even deformation across the entire barrel
• No sharp “pinch point” or crushing in one spot
• No looseness or spinning of the wire in the terminal
6. Weatherproof the joint
   Slide heat shrink over the connection and shrink it to seal out moisture. This step is crucial for long-term reliability.

Specialty Connectors Made Easy

Ratcheting crimpers really shine with more complex terminals—like OEM-style fuse block pins that crimp on both the conductor and insulation. The proper die compresses both sections in one smooth motion, giving factory-level results without vice grips or guesswork.

Upgrade Your Electrical Game

After 20 years chasing bad connections on project cars, moving to ratcheting crimpers is one of the biggest wiring upgrades you can make. Your circuits will be safer, more reliable, and far less likely to haunt you with random faults down the road.

If you’re serious about clean, dependable automotive wiring, retire the $10 crimper for emergency use only—and start building every new connection with a quality ratcheting tool. Your harness (and your sanity) will thank you.

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