Choosing the right welding wire or wire electrode is crucial for a clean weld appearance, stable arc control, and consistent material deposition.
Both the material of the base metal and the wire diameter play an important role.
Below you will learn how to select the appropriate wire electrode for your MIG/MAG welding process and what to pay attention to when handling it.
Selection by Material
Choose the wire material according to the base material and the desired mechanical requirements.
Examples:
Structural steel: Unalloyed or low-alloy solid wire (e.g. G3Si1)
Stainless steel: Stainless wire (e.g. 308L, 316L)
Aluminium: Aluminium wire (e.g. AlMg5, AlSi5)
Selection by Wire Diameter and Sheet Thickness
The wire diameter determines the current, penetration, and welding speed.
It should be chosen depending on the material thickness of the workpiece to be welded.
| Material Thickness | Recommended Wire Diameter | Typical Current |
|---|---|---|
| 0.8 – 1.5 mm | 0.6 mm | 40 – 80 A |
| 1.5 – 3.0 mm | 0.8 mm | 70 – 120 A |
| 3.0 – 6.0 mm | 1.0 mm | 100 – 180 A |
| > 6.0 mm | 1.0 mm or larger | 150 A and above |
Note:
When using the synergy mode, the wire diameter must match the values supported by your RED power source. (→ see section “Product Information, Technical Data etc.”)
Selection by Spool Type and Size
When selecting wire spools, consider not only the wire diameter but also the spool size supported by the device. For example, the RED MIG 210 SYN is designed for D200 spools.
Larger spools (e.g. D300) cannot be used with this device.
Selection by Wire Type
Different types of wire electrodes are used in MIG/MAG welding:
| Wire Type | Description | Application |
|---|---|---|
| Solid wire | Solid material wire, usually with shielding gas | For clean, spatter-reduced seams in workshop environments |
| Rutile flux-cored wire | With slag formation and shielding gas | For uniform seam surfaces, low spatter |
| Metal powder flux-cored wire | Higher melting rate, with shielding gas | For higher welding speed |
| Self-shielded flux-cored wire | Without shielding gas, with flux core | For outdoor use in windy conditions, on site and simple repair work |
Changing the Wire Electrode
When changing the wire electrode, the following components must also be adjusted to the new wire:
Wire guide (Teflon, steel, or graphite liner)
Contact tip (matching the wire diameter)
Wire feed rollers (groove shape and diameter)
This ensures that the wire is transported evenly and no feeding problems occur.
Overview Table: Material, Wire, Gas and Polarity
| Base Material | Recommended Wire | Type of Gas | Polarity | Notes |
|---|---|---|---|---|
| Structural steel | G3Si1 (solid wire) | CO₂ or Ar/CO₂ | Wire + / Ground – | Standard polarity, stable arc |
| Stainless steel | 308L, 316L (solid wire) | Ar + 2–5 % CO₂ or O₂ | Wire + / Ground – | Clean, low-spatter seam |
| Aluminium | AlMg5, AlSi5 (solid wire) | Pure argon | Wire + / Ground – | Good penetration depth, clean weld pool |
| Rutile/metal powder flux-cored wire | Type depending on material | CO₂ or Ar/CO₂ | Wire + / Ground – | Smooth arc, uniform surface |
| Self-shielded flux-cored wire | Without shielding gas | – | Wire – / Ground + | Ideal for outdoor use, wind resistant |
If you are unsure which wire electrode or spool size your RED by Lorch MIG system supports,
you will find the relevant information in the technical data of your welding machine or you can contact us directly via the contact form.