How to Crimp Battery Cable without a Crimper (Step by Step)

How to Crimp Battery Cable without a Crimper (Step by Step)

Can you use a flat nail punch, hammer, angle iron, or other tools to crimp a wire instead of an RJ45 crimper?

Using a crimper properly, you can make a good joint between a wire and a connector barrel. But if I don’t have a crimping tool, what to use?

Crimping a battery cable is not challenging, and complex machinery is not required.

Considering this, how to crimp a battery cable without a crimper? Let’s learn from the step-by-step process below.

How to Crimp Battery Cable without a Crimper?

To begin the process, you will require a few ingredients.

Cable: Make sure to choose the suitable cable for your machinery because different machine needs different cables. Since a variety of cables are available, remember the below thumb rule.

  • For dry machines like tractors, cars, etc., buy untreated copper wire.
  • For wet machines like jet skis, boats, etc., buy electroplated strands.

Solder Wire: Buy non-acidic rosin core solder wire because it is the safest to use for battery connections. The battery can get corroded or show issues when exposed to electricity if you use acidic rosin core solder wire.

Rosin Fluid: At this point, you will need to buy non-acidic rosin fluid.

Other necessary ingredients are

Step 01: Cable Preparing

Take a heavy-duty cutter set and use it to clip the cable properly. The cable needs to be clipped evenly.

Avoid using a hacksaw or other types of saw because you will end up with uneven or jagged cable ends if you do so, and working will be hard.

Step 02: Cut 1” of the Rubber Housing to Expose the Cable

At this step, you have to be highly cautious not to cut the cable strands. Don’t rush; be patient and cut the rubber housing only.

Remove any Loose Strands

To learn the suitable measurement, take assistance from terminal cable lugs. Just align it with the wire and check how long the hole is, and then cut the rubber gently to fit into the original meta wire easily.

Don’t be worried if you cut the rubber housing more than required; we will reassemble the wire later.

Step 03: Remove any Loose Strands

Before using, pull off any unwound strands using your fingers. This will increase the lifespan of your cable since you are removing any stray bits.

Step 04: Attach 4”-5” of Sheathings

After you attach the terminal, getting these sheathings will be challenging to attach. So, attach these before attaching the terminal. These sheathings will cover the exposed metal at the cable’s end when completed.

Step 05: Apply Rosin Fluid

Apply rosin fluid liberally using a cotton swab to the terminal’s inside and the exposed cables. Once this fluid is heated, a strong electrical connection occurs between the 2 bits.

Step 06: Snug the Terminal Lug into the Exposed Wires

Take the terminal lug and snug it into the exposed wires end carefully; push it as much as possible.

Step 07: Use a Flat Nail Punch to crimp the Terminal Lug

Now it is time to use a hammer. Angle iron or a flat nail punch. The punch needs to be placed in the center of the nut; hammer it hard so that the terminal gets crimped into the cable. Repeat the same process on the other side of the cable.

Step 08: Place the Terminal Lug in a Clamp

We will heat the connected area in the next step, which means the entire thing will be extremely hot.

As a result, you will not be able to hold the terminal lug with your hand. So, clamp the terminal lug down to heat the whole thing easily.

Step 09: Use High-heat Source to Heat Up the Lug and Boil Down the Rosin Fluid

The entire piece needs to look nice, and the connection has to be strong. For this, we will need to heat the lug and boil down the rosin fluid.

Take a butane torch and turn it up. Hold the cable in front of the butane torch and gently rotate it so that the whole thing gets heated. Continue heating until you see the bubble of the rosin.

Step 10: Use the non-reactive solder

Now, we will use the non-reactive solder wire in this step. Use it to solder where the bare wire started and the terminal logs ended.

It would be best to do this just after the rosin fluid started boiling. Once finished, give it a rest for 1 or 2 minutes before proceeding to the next step. The solder needs to be liquefied with enough heat.

Step 11: Cut the Exposed Wire Strands

Some loose wires may get exposed while putting the cable into the terminal. Use a wire cutter and strip them off.

Step 12: Cover the Exposed Metal with Sheathings

We attached a 4” – 5” sheathing in step # 5. Use it to cover the connected area to prevent corrosion or rust.

The connection will be protected if you do so. Similarly, the whole thing will get a nice look. This sheathing will enhance the lifespan of the battery cables.


Make sure to cut the wire cleanly. A clean cut will let you accomplish the whole project efficiently with less effort and time.


While making those connections, extreme heat is necessary. So, work in a clean and safe area. Wear safety goggles, hand gloves, and other essential safety gear.

How to crimp a battery terminal without a crimper

 Final Words 

So, isn’t the process of how to crimp a battery cable without a crimper so simple? The whole process will not let you face many challenges for sure.

You can follow these steps when you don’t have an RJ45 crimper in your hand and the work needs to be done immediately. This process’s result will be similar to using a crimping tool.

This DIY project will surely improve your confidence.

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