"100% Pure Copper Cables" is printed on a lot of $300 MIG welders right now. But copper costs significantly more than aluminum. So how do you actually know what's inside the cable jacket?
We cut one open. No guessing. No brand claims. Just a cross-section and a camera.
The Problem With "Copper" Claims at This Price Point
Copper-clad aluminum (CCA) cable looks identical to pure copper on the outside. Same orange jacket. Same connectors. You can't tell the difference until you cut it — or until it starts running hot after 20 minutes of welding.
We've cut leads from multiple machines in the $280–$350 range. The pattern: most ship with CCA or aluminum-core leads, regardless of what the listing says. The cable jacket color is not a reliable indicator.
Copper vs. Aluminum Core: What Actually Changes
| Property | 100% Copper | Aluminum / CCA |
|---|---|---|
| Conductivity | Higher ✓ | ~61% of copper |
| Heat Under Load | Runs cooler ✓ | Runs hotter |
| Flexibility Over Time | Stays flexible ✓ | Stiffens, cracks |
| Arc Stability | Less voltage drop ✓ | More voltage drop |
| Service Life | Longer ✓ | Degrades faster |
How to Check Your Leads Without Cutting
If you already own a welder and want to check your leads:
- Cut the end and look at the strands — pure copper is reddish-orange all the way through. CCA shows silver-grey in the center with a thin copper layer on the outside strands only.
- Weigh them — copper is about 3.3× heavier than aluminum by volume. A 10ft pure copper lead should feel noticeably heavy.
- Check heat after 15 minutes of welding — if the leads are uncomfortably warm near the connectors, resistance is higher than it should be.
- Flex test in cold weather — aluminum-core cables stiffen significantly below 50°F. Pure copper stays pliable.
What We Found in the ARCPEX MIG200
We cut both the ground lead and the electrode holder lead included with the ARCPEX MIG200. The cross-section on both showed consistent reddish-orange copper stranding throughout — no silver-grey aluminum core, no CCA construction.
Why This Matters More Than Most Specs
A 20A gap in actual output (like we found in Episode 1) is significant. But bad leads compound the problem: they add resistance between the machine and the work piece, which means even a machine that delivers full rated amps loses some of that output before it reaches the arc.
Pure copper leads are one of those specs that doesn't show up in a YouTube thumbnail — but you feel the difference every session.
Up Next in the Series
- Episode 3 — Can It Hold 200A for Its Rated Duty Cycle?
- Episode 4 — Is Synergic MIG Actually Easier for Beginners?
- Episode 5 — Can It Feed .023 Wire on Thin Sheet?
See the full specs: ARCPEX MIG200 — View Product →
