Selecting / Changing the Contact Tip (MIG/MAG Welding Process)

The contact tip – often also called the current nozzle – is a crucial wear part in the torch of your MIG/MAG welding machine.
It ensures that the welding current is cleanly transferred to the wire and that the wire is precisely guided through the torch.
For your RED by Lorch welding machine to operate reliably and deliver clean seams, the correct selection and proper fit of the contact tip is especially important.

Selecting the Right Contact Tip

Always choose the contact tip to match the used wire diameter.

For example, the factory-fitted contact tip on the MIG torch of the RED MIG 210 SYN is a 0.8 mm contact tip.
If you change the wire diameter, you must also adjust the contact tip accordingly.

Typical Combinations (Guideline Values)

Changing the Contact Tip – Step by Step

Here is how to proceed:

1. Switch off the machine and disconnect from the power supply
   (Protection against electric shock!)

2. Unscrew the gas nozzle

3. Unscrew the contact tip

4. Screw in the new contact tip
   tight, but do not overtighten. Hand-tight is sufficient. 

5. Reinstall the gas nozzle

Dangers and Important Safety Instructions

Risk of Burns

Contact tips can be extremely hot after welding.
Always change only after they have completely cooled down.

Safety Risk with Incorrect Contact Tip

An incorrectly sized or worn contact tip can lead to the following symptoms:

• Unstable arc

• Wire jam in the torch

• Uneven wire feed

• Loss of contact (and resulting pores, spatter, defects)

• Overloading of the torch
   

Danger from Damaged Components

Loose or damaged contact tips cause malfunctions or even short circuits.
→ Always check that they are clean, straight and tightly fastened.

Important Notes on Material Combinations

Steel / Structural Steel

• Standard: 0.8 mm wire + 0.8 mm contact tip

• Ideal for beginners with synergy operation

Stainless Steel

• Wire diameter: 0.8 mm (common)

• Contact tip identical to wire diameter

• Tip: Stainless steel tends to spatter → clean contact tip is important

Aluminium

• Wire diameter usually 1.0 mm

• Choose contact tip exactly to match → Aluminium is soft and otherwise galling occurs

• Clean, straight wire feed is particularly important

Flux-cored Wire (metal powder filled or rutile)

• Depending on wire: 0.8 or 1.0 mm

• Pay attention to special flux-cored wire contact tips as the wire is rougher

What else should be considered when changing wire?

When changing to a different wire diameter, it is not enough to just adjust the contact tip.

Additionally check/change:

• Wire feed rollers (matching wire thickness and wire type)

• Wire guide / Teflon liner / steel liner

• Gas nozzle (for special applications)

Incorrect combinations almost always lead to:

• Wire jams

• Unstable arc

• Fluctuating torch behaviour

Spare Parts & Accessories

You can find all suitable contact tips, gas nozzles, feed rollers and torch parts in the Spare Parts section.
 

Contact tips are wear parts. 
The replacement of wear parts can be carried out by end users themselves.

For repairs:
Please do not carry out any repairs on the torch or welding machine yourself.
Only trained technicians are authorised to perform repairs.

Synonyms: Current nozzle, current tip, contact tube, welding wire guide