The Harris 00D0CH8 is a deoxidized copper MIG GMAW welding wire in the ERCu classification per AWS A5.7/A5.7M. Designed specifically for GMAW (MIG) processes, it deposits welds with good electrical conductivity, strong corrosion resistance, and exceptional ductility on copper-alloyed base metals. The wire ships as a 0.045 in (1.1 mm) diameter, 30 lb spool suitable for semi-automatic or automatic MIG gun systems. It is an authorized Harris Products Group alloy, a trusted Lincoln Electric company brand, available from WeldingMart as an authorized Harris distributor.
ERCu filler metal is the go-to choice wherever copper base metals, copper pipes, copper fittings, or dissimilar metal joints between copper and mild steel demand full fusion, low porosity, and long service life. The deoxidized formulation — meaning excess oxygen is neutralized through a silicon and manganese addition — produces clean welds that resist porosity and cracking common to undifferentiated copper alloys.
| Specification | Value |
|---|---|
| AWS Classification | ERCu (AWS A5.7/A5.7M) |
| Harris Part Number | 00D0CH8 |
| Diameter | 0.045 in (1.1 mm) |
| Package | 30 lb (13.6 kg) spool |
| Tensile Strength (all-weld) | ≥ 25,000 psi (172 MPa) |
| Yield Strength | ≥ 8,000 psi (55 MPa) |
| Elongation | ≥ 30% |
| Polarity | DCEP (electrode positive) |
| Shielding Gas | 75% Ar / 25% He or 100% Ar |
| Base Metals | Copper, copper alloyed base metals, copper to mild steel |
| Copper content (typical) | ≥ 98% Cu |
| Deoxidizers | Si ≤ 0.50%, Mn ≤ 0.50% |
Per AWS A5.7, ERCu covers bare solid copper and copper-alloy electrodes and rods for gas shielded arc welding. Harris Products Group publishes full chemistry and mechanical property data at harriswelding.com.
Harris ERCu deoxidized copper MIG wire excels in industrial and commercial contexts where copper excellent corrosion resistance and good electrical conductivity are required:
- Electrical and power generation: Bus bars, switchgear, transformer windings, and motor coil repairs where copper's excellent electrical conductivity is essential.
- Plumbing and HVAC: Joining copper pipes, copper fittings, and copper tube assemblies in refrigeration, chilled-water, and potable-water systems.
- Heat exchangers and condensers: Welding deoxidized copper shells and tube sheets in condensers requiring corrosion resistance and thermal transfer efficiency.
- Marine applications: Copper-nickel piping systems, saltwater pump casings, and shipboard condenser tubing where seawater corrosion resistance is paramount.
- Chemical processing: Welding alloy components in contact with non-oxidizing acids, ammonia, and brines where copper alloys outperform stainless.
- Dissimilar metal joints: Bridging copper to mild steel for bus bar terminals, grounding assemblies, and structural copper brackets.
Copper has high thermal conductivity — roughly 6–8× that of mild steel — so preheat is critical. For section thicknesses above 1/8 in, preheat to 400–700 °F (200–370 °C) and maintain interpass temperature. Use a stringer bead technique with a slight forehand angle to minimize heat input per pass.
| Parameter | 0.045 in Wire Typical Range |
|---|---|
| Shielding Gas | 75% Ar / 25% He or 100% Ar |
| Flow Rate | 35–45 CFH |
| Polarity | DCEP |
| Wire Feed Speed | 200–350 IPM (depending on amperage) |
| Voltage | 24–30 V |
| Current (typical) | 180–260 A |
| Preheat (≥ 1/8 in thick) | 400–700 °F (200–370 °C) |
| Gun angle | 10–15° forehand (push) |
| Travel speed | Moderate — avoid long arc length |
Helium additions to the shielding gas improve arc penetration on heavy copper sections. Use a 100% argon mix for thin-gauge copper sheet below 1/8 in. Keep nozzle-to-work distance short (3/8–1/2 in) to maintain shielding coverage. Clean base metal thoroughly with a stainless-steel wire brush dedicated to copper; never share brushes with ferrous metals.
Store Harris ERCu wire in a dry environment at 40–120 °F (4–49 °C). Copper alloys absorb moisture from the atmosphere, which introduces hydrogen into the weld pool and causes porosity. Keep spools sealed in original packaging until use. Avoid contact with oil, grease, and ferrous particles that can cause copper contamination welds.
- Store vertically or horizontally — do not stack heavy spools on delicate wire
- Use copper-compatible liners (Teflon or nylon) in MIG gun cables to prevent ferritic contamination
- Clean drive rolls frequently — copper wire is soft and shavings can clog liners
- Opened spools should be returned to sealed bags or airtight containers between shifts
Harris 00D0CH8 ERCu is compatible with any CV (constant voltage) GMAW power source capable of running 0.045 in wire. Lincoln Electric power sources such as the Power MIG 256, Power Wave S350, and Invertec V350-Pro are well matched for copper MIG applications requiring precise arc control. The wire runs through standard MIG guns equipped with copper-compatible Teflon or nylon conduit liners. Do not use steel liners, which shed particles that contaminate the copper weld pool.
Recommended shielding gas: 75% Ar / 25% He for thicker sections, 100% Ar for thin gauge. Helium-enriched blends improve arc energy and fusion on sections over 3/8 in. A quality argon regulator maintains stable flow rates critical for copper welding quality. See also all welding wire and Harris 4130 Chrome-Moly MIG Wire.
- What does ERCu mean for deoxidized copper MIG welding wire?
- ERCu is the AWS A5.7 classification for bare copper and copper-alloy filler metals. "E" = electrode, "R" = rod/wire, "Cu" = copper base chemistry. The deoxidized designation confirms that Si and Mn additions remove excess oxygen, reducing porosity in the finished weld.
- What shielding gas works best with copper MIG welding wire?
- The most common choice is 75% Argon / 25% Helium (He-25). Helium additions increase arc energy and improve fusion on the high-conductivity copper base metal. For thin copper sheet (under 1/8 in), 100% Argon with a short arc length can minimize burn-through. Avoid CO₂-only or mixed CO₂ blends — CO₂ oxidizes the copper weld pool.
- Can I weld copper to mild steel with Harris ERCu?
- Yes. ERCu is rated for dissimilar metal applications joining copper to mild steel. Preheat the copper side to 400–700 °F and maintain a tight arc. Weave technique helps blend the two base metals. Be aware that weld deposits will be copper-rich, so joint design should keep filler dilution balanced for the service condition.
- Do I need to preheat copper before MIG welding?
- For sections over 1/8 in (3 mm), yes — preheat to 400–700 °F. Copper's very high thermal conductivity pulls heat away from the joint rapidly. Without preheat, the arc chases a cold base and the result is poor fusion, porosity, and cracking. Thin sheet (under 1/16 in) may not need preheat if welding is rapid and continuous.
- What is the difference between ERCu and ERCuSi-A?
- ERCu is nearly pure copper with minimal deoxidizers, best suited for welding copper and copper-to-steel joints where electrical conductivity of the deposit is important. ERCuSi-A (silicon bronze) contains 2.8–4.0% silicon and is better for brazing/braze welding thin steels, galvanized sheet, and cast iron. Choose ERCu for copper pipe, fittings, and electrical assemblies; choose ERCuSi-A for steel/iron joints that benefit from a low-melting bronze deposit.
- How do I prevent porosity when welding copper with MIG?
- The main causes of porosity in copper MIG welding are moisture, contamination, and inadequate shielding. Clean the base metal with a dedicated stainless brush. Use dry, high-purity shielding gas (99.997% minimum purity). Maintain short nozzle-to-work distance and adequate gas flow (35–45 CFH). Preheat thick sections. Check liners for contamination from ferrous particles.
- Is Harris ERCu MIG wire approved for pressure vessel or structural applications?
- AWS A5.7 ERCu is used in ASME Code Section IX qualified procedures for copper alloy pressure vessels. Consult the applicable code (ASME, AWS D1.x, or API) for your specific application. WeldingMart supplies this wire for general industrial and commercial purposes; consult your welding engineer for code-critical applications.
When selecting deoxidized copper MIG welding wire, it is important to add the right product to your cart and recommend the correct alloy for your application. The Harris ERCu welding alloy is easy to identify by its bright copper color and the AWS ERCu designation stamped on the spool label. Start by matching the wire diameter to your base metal thickness: 0.035 in for thin copper sheet, 0.045 in (this product) for 1/8–3/8 in copper plate, and 1/16 in for heavy sections. The deoxidized copper formulation means you can recommend this product with confidence for copper pipes, copper fittings, and electrical bus applications. Good electrical conductivity exists throughout the weld zone when ERCu is properly applied with 75/25 Ar/He shielding. Select this item when repair or joining of copper-alloyed base metals requires a weld that passes through-wall conductivity testing.
Harris 00D0CH8 deoxidized copper MIG wire is the production-scale format — a 30 lb spool of ERCu (deoxidized copper) classified wire at 0.045 in diameter, designed for automated GMAW lines, large-diameter copper pipe joining, copper bus bar fabrication, and heavy-deposition copper alloy surfacing. The 30 lb spool reduces change-over frequency on automated welding cells. At 0.045 in diameter, this wire runs at higher amperages (150–300 A) and deposition rates than 0.035 in ERCu wire, making it suitable for production copper welding applications where weld time per joint is a cost driver.
| Parameter | 0.045 in ERCu Typical Range |
|---|---|
| Shielding Gas | 100% Ar or 75/25 He/Ar (He increases heat for thick copper) |
| Flow Rate | 30–45 CFH |
| Polarity | DCEP |
| Wire Feed Speed | 150–350 IPM |
| Voltage | 22–28 V |
| Current | 150–300 A |
| Transfer Mode | Spray (preferred for copper); pulsed for thin gauge |
| Preheat | 200–400 °F for copper > 3/16 in (copper conducts heat away rapidly) |
| Travel Speed | 12–20 IPM; maintain consistent torch angle |
Copper's high thermal conductivity — approximately 8× greater than steel — means that heat dissipates from the weld joint very rapidly. Preheating is essential for copper sections thicker than 3/16 in; without it, the arc cannot maintain a molten weld pool and the joint cold-laps or lacks fusion. Helium-argon shielding (75% He / 25% Ar) increases arc energy and weld pool temperature, overcoming copper's thermal conductivity on thick sections. For thinner copper sheet, pure argon with spray transfer works well.
Deoxidized copper MIG wire serves a narrower but critical application set compared to silicon bronze:
- Copper-to-copper MIG welding: Joining copper bus bars, copper pipe systems, copper sheet, and copper castings with a matching-chemistry filler. ERCu produces nearly pure copper deposits with conductivity close to the base metal — important for electrical and heat transfer applications.
- Copper plumbing and HVAC systems: Large-diameter copper pipe (2 in +) that exceeds practical torch brazing diameter. MIG welding with ERCu provides production-rate joining for industrial copper piping systems.
- Copper bus bar fabrication: Electrical switchgear, transformer connections, and power distribution bus bars require joining pure copper conductors. ERCu deposits maintain high electrical conductivity at the joint (conductivity > 85% IACS typical).
- Copper surfacing and cladding: Depositing copper alloy surfaces on steel substrates for corrosion resistance, electrical contact, or bearing surface applications. The 30 lb spool is cost-effective for long cladding runs.
- Copper casting repair: Repairing bronze and copper castings with matching-chemistry filler that minimizes dilution-related color mismatch and maintains mechanical properties.
Copper behaves differently from steel in joint design because of its high thermal conductivity and lower melting point (1,981 °F for pure Cu vs. 2,600 °F for steel). Joint design considerations:
- Butt joints: V-groove (60–70° included angle) with 1/16 in root opening and backing bar (copper or stainless). Without backing, copper's fluid molten pool drops through tight root openings.
- Lap and T-joints: Clean mating surfaces and tight fit-up essential. Copper weld pools are very fluid — gaps cause drop-through. Use copper or stainless backing strips on open joints.
- Preheat evenly: For thick copper, use multiple torch passes to preheat 6–8 in on each side of the joint before welding. Check temperature at multiple points with contact thermometer.
- Work speed: Once copper is preheated and the arc is established, maintain steady travel speed. Stopping mid-bead causes cratering and porosity in copper welds.
Harris 00D0CH8 is an authorized WeldingMart product. For TIG welding applications, see Harris Deoxidized Copper TIG Rod. For lighter-gauge copper joining, Harris's smaller diameter ERCu spools are available. See all MIG wire and welding alloys.
Harris 00D0CH8 deoxidized copper MIG wire is the production-scale format — a 30 lb spool of ERCu (deoxidized copper) classified wire at 0.045 in diameter, designed for automated GMAW lines, large-diameter copper pipe joining, copper bus bar fabrication, and heavy-deposition copper alloy surfacing. The 30 lb spool reduces change-over frequency on automated welding cells. At 0.045 in diameter, this wire runs at higher amperages (150–300 A) and deposition rates than 0.035 in ERCu wire, making it suitable for production copper welding applications where weld time per joint is a cost driver.
| Parameter | 0.045 in ERCu Typical Range |
|---|---|
| Shielding Gas | 100% Ar or 75/25 He/Ar (He increases heat for thick copper) |
| Flow Rate | 30–45 CFH |
| Polarity | DCEP |
| Wire Feed Speed | 150–350 IPM |
| Voltage | 22–28 V |
| Current | 150–300 A |
| Transfer Mode | Spray (preferred for copper); pulsed for thin gauge |
| Preheat | 200–400 °F for copper > 3/16 in (copper conducts heat away rapidly) |
| Travel Speed | 12–20 IPM; maintain consistent torch angle |
Copper's high thermal conductivity — approximately 8× greater than steel — means that heat dissipates from the weld joint very rapidly. Preheating is essential for copper sections thicker than 3/16 in; without it, the arc cannot maintain a molten weld pool and the joint cold-laps or lacks fusion. Helium-argon shielding (75% He / 25% Ar) increases arc energy and weld pool temperature, overcoming copper's thermal conductivity on thick sections. For thinner copper sheet, pure argon with spray transfer works well.
Deoxidized copper MIG wire serves a narrower but critical application set compared to silicon bronze:
- Copper-to-copper MIG welding: Joining copper bus bars, copper pipe systems, copper sheet, and copper castings with a matching-chemistry filler. ERCu produces nearly pure copper deposits with conductivity close to the base metal — important for electrical and heat transfer applications.
- Copper plumbing and HVAC systems: Large-diameter copper pipe (2 in +) that exceeds practical torch brazing diameter. MIG welding with ERCu provides production-rate joining for industrial copper piping systems.
- Copper bus bar fabrication: Electrical switchgear, transformer connections, and power distribution bus bars require joining pure copper conductors. ERCu deposits maintain high electrical conductivity at the joint (conductivity > 85% IACS typical).
- Copper surfacing and cladding: Depositing copper alloy surfaces on steel substrates for corrosion resistance, electrical contact, or bearing surface applications. The 30 lb spool is cost-effective for long cladding runs.
- Copper casting repair: Repairing bronze and copper castings with matching-chemistry filler that minimizes dilution-related color mismatch and maintains mechanical properties.
Copper behaves differently from steel in joint design because of its high thermal conductivity and lower melting point (1,981 °F for pure Cu vs. 2,600 °F for steel). Joint design considerations:
- Butt joints: V-groove (60–70° included angle) with 1/16 in root opening and backing bar (copper or stainless). Without backing, copper's fluid molten pool drops through tight root openings.
- Lap and T-joints: Clean mating surfaces and tight fit-up essential. Copper weld pools are very fluid — gaps cause drop-through. Use copper or stainless backing strips on open joints.
- Preheat evenly: For thick copper, use multiple torch passes to preheat 6–8 in on each side of the joint before welding. Check temperature at multiple points with contact thermometer.
- Work speed: Once copper is preheated and the arc is established, maintain steady travel speed. Stopping mid-bead causes cratering and porosity in copper welds.
Harris 00D0CH8 is an authorized WeldingMart product. For TIG welding applications, see Harris Deoxidized Copper TIG Rod. For lighter-gauge copper joining, Harris's smaller diameter ERCu spools are available. See all MIG wire and welding alloys.
Harris deox copper MIG wire produces weld deposits with high copper purity and good electrical conductivity. When welding copper to steel, dissimilar metal joints require careful parameter selection — the high thermal conductivity of copper base metals draws heat away rapidly, while the steel side retains heat longer. Overlaying steel with deox copper builds up copper surfaces on steel substrates for electrical contact, heat transfer, and corrosion resistance applications. The ERCu classification produces high purity deposits that maintain copper conductivity properties in the weld zone.
To promote sound weld joints on copper base materials, preheat thick copper sections to 400–600 °F before welding. Without preheat, copper base metals dissipate arc heat faster than it can build a molten pool, resulting in cold-laps and incomplete fusion. Once proper preheat is achieved, the weld pool forms quickly and deposits flow well — completing trouble free welds on copper requires maintaining preheat throughout the joint.
Current and shielding gas selection together determine deposit quality. For oxyacetylene welding of copper, a slightly reducing flame is used with flux. For GMAW, 100% Ar or 75 He/25 Ar shielding is required. Helium additions increase arc energy, which is important when welding copper alloyed base metals thicker than 3/16 in. Argon-only shielding is adequate for thin copper sheet where thermal mass is lower. The combination of correct current and shielding gas selection produces high purity deposits that resist porosity and maintain the good electrical conductivity that makes copper valuable in the first place.
Ready to add Harris deox copper MIG wire to your order? The 00D0CH8 is available online at WeldingMart — add to cart for fast shipping to your shop. This wire is used to weld copper to steel, copper-to-copper, and overlaying steel with copper deposits for corrosion resistance. The ERCu classification is electrically conductive, making it the match for joining bus bars, transformer leads, and electrical copper components. The free-running, low-spatter arc of ERCu MIG wire makes it a practical choice for fabricators who add copper weld jobs to their workflow occasionally.
Borax flux is used with oxyacetylene welding of copper — for GMAW (MIG), no flux is needed since the argon shielding replaces the flux function. The borax flux comparison is a useful differentiator for shops transitioning from OA copper welding to MIG: the match between the two processes is the deoxidizing function — borax does it chemically in OA, the phosphorus deoxidizer in ERCu does it in the weld pool during GMAW. Email WeldingMart for bulk pricing on the 30 lb spool if your shop uses deox copper MIG wire regularly. Customer reviews confirm that 00D0CH8 feeds freely and produces trouble-free welds on copper bus bar, pipe, and plating applications.
For oxyacetylene copper welding, boric acid or borax flux is used to prevent oxidation. In GMAW with ERCu wire, the argon shielding replaces chemical flux entirely, and the phosphorus deoxidizing agents in the wire protect the weld pool without added flux. Boric acid references come from legacy copper OA procedures — GMAW practitioners do not need flux. A slightly oxidizing flame in OA copper welding produces oxide inclusions; in GMAW, deoxidizing agents in the wire prevent this.
Contact tip size selection for 0.045 in deox copper wire: use a 0.045 in (or 0.047 in oversized) copper contact tip. Tip size matters for copper alloy wire — standard steel-spec tips wear faster with copper. Sizes larger than the wire diameter by 0.002 in reduce tip wear. Good color match of the ERCu deposit to copper base plate components is important for visible joints in architectural copper and bus bar fabrication. The weld is easy flowing when preheat is correct — porosity free deposits on copper base plate are achievable with clean metal, proper preheat, and correct current. Welding copper to steel produces a dissimilar-metal joint; use copper base plate for backing when welding copper to steel panels to prevent base plate burn-through. Email WeldingMart@weldingmart.com for OEM pricing or to confirm availability of deox copper wire sizes larger than 0.045 in for heavy-deposition applications. Used to weld both copper and copper-to-steel assemblies, Harris ERCu provides a reliable, commercially pure copper deposit.
Key features of Harris 00D0CH8 deoxidized copper MIG wire include: rigidly controlled manufacturing, consistent chemistry in the ERCu classification, easy-flowing arc on preheated copper, and compatibility with multiple copper base metals. The wire conforms to AWS A5.7 ERCu requirements. Product details documentation is available at the WeldingMart website and from Harris Products Group directly.
Available in two sizes at WeldingMart — 0.035 in and 0.045 in diameter — deox copper MIG wire heats copper base metals efficiently when the preheat is correctly established. Copper needs preheat because it heats and dissipates heat so rapidly that small amounts of additional arc heat cannot overcome thermal conductivity without preheat. The neutral to slightly oxidizing shielding gas (100% Ar) provides a stable arc. Overlay copper deposits on steel tanks, pressure vessels, and base plate fabrications for corrosion resistance. The image of a copper overlay on carbon steel base plate demonstrates the color contrast and bond quality achievable with ERCu MIG wire. Enter the product number 00D0CH8 on the WeldingMart website to view stock status. Acts as deoxidizing agents, the silicon and phosphorus in ERCu wire remove small amounts of oxygen from the weld pool. Good electrical conductivity exists in the deposited ERCu weld metal — this is a primary reason to specify deoxidized copper wire instead of a steel overlay when conductivity is needed. The wire conforms to AWS A5.7, and documentation of this classification is available from Harris. Email WeldingMart for details on volume pricing and availability for sizes larger than the standard 30 lb spool.