Esc

Search products, guides and expert answers by name, SKU, specification or trade slang.

Browse the full catalogue →
Welding Consumables

Choosing MMA Electrodes by Application

Which MMA electrode to use for mild steel, structural steel, outdoor, vertical and pipe welding — plus how to choose the right electrode size (2.5, 3.2, 4.0 mm).

7questions answered
2 minapprox. read

For most mild steel use 6013; for structural steel, vertical-up and high-strength work use 7018 low-hydrogen electrodes; for pipe root passes use 6010; and outdoors MMA electrodes generally outperform MIG because they need no shielding gas. Electrode size is then matched to material thickness, from 2.5 mm for thin material up to 3.2 mm and 4.0 mm for heavier fabrication.

This guide pairs the right electrode and size to common applications.

Which electrode is best for mild steel?

6013 electrodes are suitable for most general mild steel fabrication because they are easy to use and produce good-quality welds. For structural or coded welding, 7018 electrodes are often preferred due to their superior mechanical properties.

Which electrode is best for structural steel?

7018 low-hydrogen electrodes are widely used for structural steel because they produce high-strength welds with excellent toughness and reduced hydrogen cracking. Always follow the relevant welding procedure specification (WPS) where applicable.

Which electrode is best for outdoor welding?

MMA electrodes are generally better suited to outdoor welding than MIG because they do not require shielding gas. 6013 electrodes are suitable for general work, while 7018 electrodes are preferred for structural applications.

Which electrode is best for vertical welding?

7018 electrodes are commonly used for vertical-up welding due to their good mechanical properties and controlled weld pool. Correct technique and suitable welding parameters are essential for successful vertical welding.

Which electrode is best for pipe welding?

6010 electrodes are widely used for root passes on pipeline welding because they provide deep penetration. Fill and cap passes often use 7018 electrodes for strength and toughness. The choice depends on the welding procedure and material specification.

What size MMA electrode should I use?

Electrode size depends on material thickness and welding current. As a general guide:

  • 2.5 mm — suitable for thinner materials.
  • 3.2 mm and 4.0 mm — commonly used for heavier fabrication.

Selecting the correct size improves penetration and weld quality.

[VERIFY: the source gives no specific amperage ranges per electrode size or recommended current/polarity settings (beyond 6010 being DC). Do not publish amp ranges or a polarity table without confirming against a manufacturer datasheet or WPS.]

Application quick reference

ApplicationRecommended electrode
General mild steel6013
Structural / coded7018
Outdoor (general)6013
Outdoor (structural)7018
Vertical-up7018
Pipe root pass6010
Pipe fill / cap7018

Talk to our technical team

Get the right specification, first time

A short conversation beats guesswork. Our technical team assesses your processes, materials and workshop, then recommends the right welding consumables — from a single product to a complete specification.

Related guides

Open an account

Trade-only · No minimum order · Free UK delivery over £150. Request an account and get access to the full range.