The reliability and security of your electrical connections depend on how you terminate them. Terminating electrical wires involves attaching a terminal connector to the stripped end of a wire and securing it through soldering or crimping to form a robust connection.
Both crimping and soldering create strong electrical connections when done correctly. However, crimping is ideal for adventure vehicles due to its cold-weld mechanical bond, which offers superior resistance to temperature cycling and vibrations.
Each method has unique processes, requirements and performance characteristics, along with its own advantages and drawbacks. In this guide, we explore these aspects to help you choose the best termination method for wiring accessories and appliances in your campervan, caravan or RV.
What Is the Difference Between Crimping and Soldering?
While both methods involve attaching terminal connectors to a wire's ends, the processes of crimping and soldering differ significantly. This results in distinct connection types with varying performance and reliability, as we shall see later in the article.
How Soldering Electrical Wires Works
Soldering involves joining an electrical wire to a terminal connector using a fusible metal filler called solder, which has a lower melting point than the wire's conductor. To create a soldered connection, you heat the solder to its melting point, allow the molten filler to flow into and around the wire joint, and then let it cool.
As the soldered connection cools, it forms a strong, chemically and electrically conductive bond between the joined wire and terminal connector.
How Crimping Electrical Wires Works
In contrast, crimping involves compressing a terminal connector around the stripped end of an electrical wire. To do this, you insert the wire's stripped end into the connector's collapsible barrel. Then, you compress the barrel using a dedicated crimping tool, creating a strong mechanical and electrical bond between the connector and the wire.
What Tools Do You Need to Solder or Crimp Electrical Wires?
As the processes differ, the tools, materials and steps required for soldering and crimping also vary significantly.
How to Solder Wires to Terminal Connectors
Generally, most terminal connectors can be soldered to a wire. However, you must ensure the wire ends are clean, free of debris and show no signs of oxidation (e.g. discolouration or blue-green tarnish), as these can prevent the molten solder from bonding effectively with the conductor.
Soldering requires the following tools and materials:
- Terminal connectors and wires to be joined
- Wire strippers to remove insulation
- Solder alloy to form the electrical bond
- A soldering gun (or soldering iron) to melt the solder
- A brass wool tip cleaner, cellulose scrubber sponge or similar tool for cleaning the soldering gun (or soldering iron) tip
Once you have gathered these items:
- Strip 5–10 mm of insulation from the ends of the wires to be joined.
- Confirm the wire ends and the connector's barrel are clean, free of oxidation and debris.
- Apply a thin layer of solder to the bare wire ends (tinning the wire).
- Insert your tinned wire end into the connector's barrel, ensuring it is fully seated.
- Heat the connector with the soldering gun (or soldering iron) for a few seconds. Then, apply solder to the junction until the molten filler flows into the connection.
- Once the connection has enough molten filler, stop feeding the solder. Then, remove the heat source from the connector and allow the connection to cool for 5–10 seconds to form a secure bond.
Important notes: Instead of a soldering gun, you can use a heat gun or blow torch to heat your terminal connector for soldering. The steps above are based on soldering wires to compression lugs for connections to battery studs and busbars, but they also apply to ring terminals, spade connectors and other connectors with a barrel end.
How to Crimp Wires to Terminal Connectors
Crimping typically requires terminal connectors with a barrel end designed for wire insertion. The dedicated crimping tool you use for this process has jaws suited to each barrel diameter.
Unlike soldering, crimping relies on mechanical compression to bond the connector's conductive metal to the wire. However, you must still ensure the wire and connector are free of debris or oxidation to maintain conductivity.
To crimp an electrical wire, you will require:
- Terminal connectors and wires to be joined
- Wire strippers to remove insulation
- A crimping tool to crimp the wires
Once you have these items:
- Strip 5–10 mm of insulation from the wire ends.
- Confirm that the stripped wire ends and the connector barrel are free of oxidation and debris.
- Insert the stripped wire end into the connector's barrel, ensuring no strands are fraying outside the barrel.
- Select the appropriate die or jaw on the crimping tool for the wire and connector size. Then, position the connector's barrel in the die and squeeze the tool firmly and steadily until the connection is fully compressed.
A properly crimped connection should be tight, with the connector immovable even under a strong pulling force.
Can You Use Pliers Instead of a Crimping Tool?
Some of our clients have asked if pliers can substitute for a crimping tool. Yes, you can use pliers to crimp electrical wires in your campervan, caravan or RV.
However, crimping with pliers applies uneven pressure on the wire barrel, risking a weak or inconsistent connection that may loosen over time. Pliers also lack the specialised dies with special jaws to grab the connector's barrel.
Therefore, for reliable and safe electrical wire connections, use a dedicated crimping tool. Pliers are only suitable for temporary fixes, such as repairing damaged wiring off-grid.
Is Crimping or Soldering More Reliable for Camper Wiring?
Both crimping and soldering can produce reliable connections when done correctly with appropriate materials. However, the resulting connections will still differ in conductivity, pullout strength, durability and longevity.
Conductivity
Properly executed soldering and crimping yield comparable electrical connections. However, common solder alloys (either tin-lead or lead-free) have slightly higher electrical resistance than copper. This introduces a minor increase in resistance, slightly reducing conductivity.
Crimping, however, relies on direct metal-to-metal contact between the wire and connector, avoiding additional resistance from solder. A properly crimped connection also forms a gas-tight mechanical bond, maximising surface contact and minimising resistance.
Pullout Strength
In campervans and RVs, strong connections are critical to withstand mechanical stress from vibrations or accidental pulling, such as when driving on rough roads.
Crimped connections excel in pullout strength tests as they create what we call a “cold weld” mechanical bond. The connection is so strong that the wire strands typically break instead of pulling out of the barrel.
On the other hand, soldered connections rely on the solder filler bonding with the wire and connector. If the solder does not bond properly, the joint will be weak and prone to fracturing under stress, such as repeated pulling or vibrations. Soldered joints can also be brittle, increasing the risk of cracks and the connection breaking.
Durability and Longevity
Frequent repairs to electrical connections, especially in hard-to-access areas, can be time-consuming and inconvenient.
Thankfully, crimped connections are highly durable, with their cold-weld bond resisting stress from vibrations, pulling or bending. Since crimping occurs at ambient temperatures, the joint can also withstand high temperatures without degrading.
Meanwhile, soldered connections, formed with molten solder that cools, risk weakening or melting under high temperatures, potentially causing connection failure. Their brittleness also makes them susceptible to cracking under mechanical stress.
Environmental Protection
Neither of these two wire termination methods inherently produces a fully environment-resistant connection. True, soldered joints create a metallurgical bond that seals against moisture and air, protecting the wire and connector from corrosion. However, solder is vulnerable to degradation in high-temperature or high-vibration environments.
On the other hand, crimped connections offer strong mechanical bonds resistant to temperature, stress and vibrations. However, they lack inherent insulation unless provided by the connector.
To fully protect either type of connection from environmental elements or accidental contact, consider heat-shrink tubing. Heat shrink forms a robust, waterproof seal when heated. Many terminal connectors now include preinstalled heat-shrink insulation for this purpose.
Ease of Use
Both crimping and soldering are straightforward if you have basic skills, but crimping is simpler. With a crimping tool, you only position the connector and wire in the appropriate die and squeeze to create a secure bond.
Meanwhile, soldering requires more skill to produce reliable joints. Without proper technique, your soldered connections may be brittle or have poor electrical contact, leading to early failure.
Also, soldering requires more tools (soldering gun, solder, cellulose scrubber sponge and sometimes flux), making it less convenient while off-grid.
Crimping vs Soldering: Pros and Cons at a Glance
At this point, we can all agree that crimping and soldering wire connections have their ups and downsides. Below is a summary of these advantages and disadvantages:
| Advantages of Crimping Electrical Wire Connections | Advantages of Soldering Electrical Wire Connections |
|---|---|
|
|
Disadvantages of Crimping
|
Disadvantages of Soldering
|
Should You Crimp or Solder Your Camper Wiring?
The best wire termination method for the wiring in your campervan, caravan or RV depends on the application, available components and the number of connections you're making.
If all the needed items are available, consider soldering if:
- You're working with very thin electrical cables
- You need temporary connections that you can separate with ease
- You're terminating a wire already mounted in a hard-to-access area
- The connection won't be exposed to high mechanical stress or high temperatures
On the other hand, terminate your electrical wires by crimping if:
- A mechanically strong connection is critical
- You're working with very thick electrical cables
- You're terminating a high volume of electrical wires
- You need an electrical connection for the most extreme environments
Frequently Asked Questions
Which is stronger, a crimped or a soldered connection?
A properly crimped connection is generally stronger under mechanical stress. Its cold-weld bond has such high pullout strength that the wire strands typically break before the wire pulls out of the barrel, whereas soldered joints can be brittle and prone to cracking under vibration or repeated pulling.
Can I crimp wires with ordinary pliers?
You can, but only for temporary fixes such as repairing damaged wiring off-grid. Pliers apply uneven pressure and lack specialised dies, risking a weak or inconsistent connection that may loosen over time. For reliable, safe connections, always use a dedicated crimping tool.
Do crimped connections need extra protection from moisture?
Yes. Crimped connections lack inherent insulation unless the connector provides it. Heat-shrink tubing forms a robust, waterproof seal when heated, and many terminal connectors now come with preinstalled heat-shrink insulation for this purpose.
How much insulation should I strip before terminating a wire?
Strip 5–10 mm of insulation from the wire ends, then confirm the bare conductor and the connector's barrel are clean and free of oxidation and debris before crimping or soldering.
Ready to wire your rig with connections that last? Browse our full range of terminal connectors at Campervan Builders and set up your campervan, caravan or RV electrics for the long haul.
