Practical answers on choosing, checking and looking after the filters, plates and small parts used inside a model-specific welding helmet.
How do I check an auto-darkening filter is working before I weld?
Most makers tell you to test the filter before every job. Press the test button, if your helmet has one, and the lens should darken briefly and then return to its light state. Some designs need you to strike an arc on a scrap piece instead.
If the lens does not darken, check the battery or the solar cell and sensors first. If it still does not darken, or it darkens inconsistently, do not weld in it. Stop, and have the filter checked or replaced. Never carry on welding with a filter that fails to darken.
What does the shade number on a welding filter mean, and which shade do I need?
The shade number tells you how dark the filter is when it is working: a higher number means a darker lens and less light reaching your eyes. The right shade depends on the welding process, the current and the work, so low-current TIG needs a different shade from heavy MIG or stick welding.
Use the shade chart in the helmet instructions or the standard it refers to, and do not guess. If you are unsure, ask your supervisor or our team. Choosing a shade that is too light is a real eye-protection risk, whereas one that is too dark simply makes the weld pool harder to see.
What do the four numbers in an optical class rating mean?
Auto-darkening filters are often marked with four digits, such as 1/1/1/2. They describe four separate qualities: how distorted the image is, how much the lens scatters light, how even the darkness is across the lens, and how much the shade changes when you look through it at an angle.
In general a lower digit is better, and 1 is the top grade. A filter with good ratings gives a clearer, less tiring view, which matters if you weld for long periods or on fine work. When you order a spare filter, compare these four digits as well as the size and shade range.
What are the sensitivity and delay controls on an auto-darkening filter for?
Sensitivity sets how easily the filter reacts to light. Set it higher for low-current welding such as fine TIG work, where the arc is dim, and lower if the filter keeps darkening from bright background light or other welders nearby.
Delay sets how long the lens stays dark after the arc stops. A short delay suits tack welding where you want to see quickly. A longer delay suits higher-current work, because the weld stays bright for a moment after the arc goes out. The settings differ between filters, so follow the helmet instructions.
Does a lighter shade number or the clear state mean my eyes are unprotected?
No. The shade number only describes how dark the lens is. A quality welding filter is designed to block harmful ultraviolet and infrared radiation in every state, including the light state, so the filter protects you even before the arc strikes.
That protection depends on the filter being undamaged. A cracked, pitted or badly scratched filter, or a missing protection plate, can let the lens fail or be damaged further. Ultraviolet exposure from the arc can cause arc eye, so never lift the helmet to check a weld while the arc is still running.
How do I work out which spare part fits my helmet?
Start with the model name and any markings on the helmet shell and on the filter itself, because these helmets are made in families and the parts differ between them. This is why parts are usually grouped by helmet model.
Measure the old part, because size is a key check: the length and width of a plate or filter must match. Then compare the shade range and optical class with the old one. Check the manual or parts diagram for the part name, such as an inner protection plate, filter holder or retaining spring. If you are not sure, our team can help you match it.