Q&A topic

Materials: 68 questions answered

• Can you weld aluminium with a MIG welder?

  Yes, with two conditions: the machine supports a spool gun or has an aluminium-capable drive, and you use 100% argon with aluminiu…

• How to weld mild steel

  To weld mild steel: use MIG or stick, gasless flux-core outdoors, filler matched to the parent metal (ER70S-6 MIG wire, E48xx stic…

• What filler wire or rod for mild steel?

  For mild steel use ER70S-6 MIG wire, E48xx stick rods, ER70S-2 TIG rod. Matching filler to the parent grade is the rule — mismatch…

• Best welding process for mild steel?

  The best process for mild steel is MIG or stick, gasless flux-core outdoors — chosen for how the metal conducts heat and what cont…

• Common problems when welding mild steel

  Common mild steel welding problems: porosity from dirty steel, burn-through on thin sheet, and cold laps from too little heat. All…

• How hot and fast: amp and speed tips for mild steel

  Baseline (40 A/mm MIG rule) — then set travel speed by watching the pool, not the clock: a consistent-width bead with proper wetti…

• Preparing mild steel for welding

  Prepare mild steel by cleaning grind back to bright metal at least 20 mm each side of the joint. On this material, cleanliness dec…

• How to weld stainless steel

  To weld stainless steel: use TIG for quality, MIG with tri-mix or 98/2 argon-CO2 for speed, filler matched to the parent metal (ER…

• What filler wire or rod for stainless steel?

  For stainless steel use ER308L (304 grade), ER316L (316 grade) — match the parent metal. Matching filler to the parent grade is th…

• Best welding process for stainless steel?

  The best process for stainless steel is TIG for quality, MIG with tri-mix or 98/2 argon-CO2 for speed — chosen for how the metal c…

• Common problems when welding stainless steel

  Common stainless steel welding problems: sugaring (back-side oxidation), distortion from retained heat, and carbon-steel contamina…

• How hot and fast: amp and speed tips for stainless steel

  About 10% less current than mild steel — then set travel speed by watching the pool, not the clock: a consistent-width bead with p…

• Preparing stainless steel for welding

  Prepare stainless steel by cleaning dedicated stainless brushes and discs — carbon steel contamination causes rust later. On this …

• How to weld aluminium

  To weld aluminium: use AC TIG for quality, MIG with a spool gun for speed, 1.6 mm+ only, filler matched to the parent metal (ER404…

• What filler wire or rod for aluminium?

  For aluminium use ER4043 (general) or ER5356 (stronger, better on 5xxx alloys). Matching filler to the parent grade is the rule — …

• Best welding process for aluminium?

  The best process for aluminium is AC TIG for quality, MIG with a spool gun for speed, 1.6 mm+ only — chosen for how the metal cond…

• Common problems when welding aluminium

  Common aluminium welding problems: porosity from the oxide layer, feed jams from soft wire, and blow-through because the pool give…

• How hot and fast: amp and speed tips for aluminium

  More current per mm than steel (40–55 A/mm TIG) — aluminium dumps heat into the job — then set travel speed by watching the pool, …

• Preparing aluminium for welding

  Prepare aluminium by cleaning stainless brush the oxide layer off right before welding — it reforms within hours. On this material…

• How to weld cast iron

  To weld cast iron: use stick with nickel (ENiFe) rods, low and slow with preheat, filler matched to the parent metal (ENiFe-CI (ni…

• What filler wire or rod for cast iron?

  For cast iron use ENiFe-CI (nickel-iron) rods; plain steel rods crack. Matching filler to the parent grade is the rule — mismatche…

• Best welding process for cast iron?

  The best process for cast iron is stick with nickel (ENiFe) rods, low and slow with preheat — chosen for how the metal conducts he…

• Common problems when welding cast iron

  Common cast iron welding problems: cracking from cooling too fast, porosity from impurities, and trying to weld one long bead. Fix…

• How hot and fast: amp and speed tips for cast iron

  Low current for the rod size, many small passes — then set travel speed by watching the pool, not the clock: a consistent-width be…

• Preparing cast iron for welding

  Prepare cast iron by cleaning grind the casting skin off, drill small stopper holes at crack ends. On this material, cleanliness d…

• How to weld galvanised steel

  To weld galvanised steel: use flux-core or stick 6013/7018 on it, MIG if you grind the coating back, filler matched to the parent …

• What filler wire or rod for galvanised steel?

  For galvanised steel use same as mild steel; silicon-rich wires handle zinc slightly better. Matching filler to the parent grade i…

• Best welding process for galvanised steel?

  The best process for galvanised steel is flux-core or stick 6013/7018 on it, MIG if you grind the coating back — chosen for how th…

• Common problems when welding galvanised steel

  Common galvanised steel welding problems: porosity and spatter from boiling zinc, plus flu-like metal fume fever from the smoke. F…

• How hot and fast: amp and speed tips for galvanised steel

  Slightly higher amps than bare steel for the same result — then set travel speed by watching the pool, not the clock: a consistent…

• Preparing galvanised steel for welding

  Prepare galvanised steel by cleaning grind the gal off the weld zone where you can — it's faster than fighting porosity. On this m…

• How to weld 4130 chromoly

  To weld 4130 chromoly: use TIG with ER80S-D2 filler, filler matched to the parent metal (ER80S-D2, or ER70S-2 for less critical tu…

• What filler wire or rod for 4130 chromoly?

  For 4130 chromoly use ER80S-D2, or ER70S-2 for less critical tube work. Matching filler to the parent grade is the rule — mismatch…

• Best welding process for 4130 chromoly?

  The best process for 4130 chromoly is TIG with ER80S-D2 filler — chosen for how the metal conducts heat and what contamination cos…

• Common problems when welding 4130 chromoly

  Common 4130 chromoly welding problems: heat-affected-zone cracking and loss of toughness if you weld too hot or too fast. Fix with…

• How hot and fast: amp and speed tips for 4130 chromoly

  Similar to mild steel; control heat input to protect the HAZ — then set travel speed by watching the pool, not the clock: a consis…

• Preparing 4130 chromoly for welding

  Prepare 4130 chromoly by cleaning acetone wipe, clean tungsten, tight fit-up. On this material, cleanliness decides weld quality m…

• Can you mig welding mild steel?

  Yes — perfect — the default. MIG on mild steel: match technique to the material; filler ER70S-6 MIG wire, E48xx stick rods, ER70S-…

• Can you tig welding mild steel?

  Yes — yes, when cosmetics matter. TIG on mild steel: MIG or stick, gasless flux-core outdoors; filler ER70S-6 MIG wire, E48xx stic…

• Can you stick welding mild steel?

  Yes — yes, the site standard. Stick on mild steel: match technique to the material; filler ER70S-6 MIG wire, E48xx stick rods, ER7…

• Can you flux-core welding mild steel?

  Yes — yes, ideal outdoors. Flux-core on mild steel: match technique to the material; filler ER70S-6 MIG wire, E48xx stick rods, ER…

• Can you laser welding mild steel?

  Yes — yes, sheet speed work. Laser on mild steel: match technique to the material; filler ER70S-6 MIG wire, E48xx stick rods, ER70…

• Can you mig welding stainless steel?

  Yes — yes with 98/2 mix or tri-mix. MIG on stainless steel: match technique to the material; filler ER308L.…

• Can you tig welding stainless steel?

  Yes — the quality default. TIG on stainless steel: TIG for quality, MIG with tri-mix or 98/2 argon-CO2 for speed; filler ER308L.…

• Can you stick welding stainless steel?

  Yes — yes with stainless rods. Stick on stainless steel: match technique to the material; filler ER308L.…

• Can you flux-core welding stainless steel?

  Yes — avoid — cleanup ruins the point. Flux-core on stainless steel: match technique to the material; filler ER308L.…

• Can you laser welding stainless steel?

  Yes — excellent — minimal discolouration. Laser on stainless steel: match technique to the material; filler ER308L.…

• Can you mig welding aluminium?

  Yes — yes with spool gun + argon, 1.6 mm+. MIG on aluminium: match technique to the material; filler ER4043.…

• Can you tig welding aluminium?

  Yes — AC TIG is the benchmark. TIG on aluminium: AC TIG for quality, MIG with a spool gun for speed, 1.6 mm+ only; filler ER4043.…

• Can you stick welding aluminium?

  Yes — possible with ally rods, rarely worth it. Stick on aluminium: match technique to the material; filler ER4043.…

• Can you laser welding aluminium?

  Yes — yes, with wire feed and care on reflectivity. Laser on aluminium: match technique to the material; filler ER4043.…

• Can you mig welding cast iron?

  Yes — possible with nickel wire, specialist work. MIG on cast iron: match technique to the material; filler ENiFe-CI.…

• Can you tig welding cast iron?

  Yes — yes with ENiFe rod — maximum control. TIG on cast iron: stick with nickel (ENiFe) rods, low and slow with preheat; filler EN…

• Can you stick welding cast iron?

  Yes — the default: nickel rods, preheat, slow cooling. Stick on cast iron: match technique to the material; filler ENiFe-CI.…

• Can you laser welding cast iron?

  Yes — emerging repair use; niche. Laser on cast iron: match technique to the material; filler ENiFe-CI.…

• Can you mig welding galvanised steel?

  Yes — yes but grind the coating back where you can. MIG on galvanised steel: match technique to the material; filler same as mild …

• Can you tig welding galvanised steel?

  Yes — yes on cleaned zones; fume caution. TIG on galvanised steel: flux-core or stick 6013/7018 on it, MIG if you grind the coatin…

• Can you stick welding galvanised steel?

  Yes — good tolerance, more fume. Stick on galvanised steel: match technique to the material; filler same as mild steel; silicon-ri…

• Can you flux-core welding galvanised steel?

  Yes — the best tolerance of the arc processes. Flux-core on galvanised steel: match technique to the material; filler same as mild…

• Can you laser welding galvanised steel?

  Yes — avoid — zinc boils violently. Laser on galvanised steel: match technique to the material; filler same as mild steel; silicon…

• Can you mig welding 4130 chromoly?

  Yes — possible with ER80S-6-class wire. MIG on 4130 chromoly: match technique to the material; filler ER80S-D2, or ER70S-2 for les…

• Can you tig welding 4130 chromoly?

  Yes — the motorsport standard with ER80S-D2. TIG on 4130 chromoly: TIG with ER80S-D2 filler; filler ER80S-D2, or ER70S-2 for less …

• Can you stick welding 4130 chromoly?

  Yes — yes with matching low-alloy rods. Stick on 4130 chromoly: match technique to the material; filler ER80S-D2, or ER70S-2 for l…

• Can you flux-core welding 4130 chromoly?

  Yes — rarely used. Flux-core on 4130 chromoly: match technique to the material; filler ER80S-D2, or ER70S-2 for less critical tube…

• Can you laser welding 4130 chromoly?

  Yes — production tube work, growing. Laser on 4130 chromoly: match technique to the material; filler ER80S-D2, or ER70S-2 for less…

• Why do my aluminium welds crack?

  Aluminium welds crack from centreline hot cracking: wrong filler (or no filler), too-constrained joints, or cracking impurities. T…

• Why did my stainless weld rust?

  Stainless welds rust from iron contamination (steel brushes/discs touching the weld), heat tint left un-treated, or wrong filler f…

• Is real stainless steel ever magnetic?

  MYTH BUSTED: “Genuine stainless steel is never magnetic.” — rated False after two-pass adversarial verification against official A…