Welding helmet lenses are to protect the welder from eye damage and flash burns. Welding helmet lenses are available in a variety of optical densities that are designed to filter intensity of light produced by the arc. The light properties of the lens depends on the welding type being used, the welder current and material being welded. lenses are available in different colors, the most popular being green, gold or blue.
Suggested Lens Shades
|Metal Thickness Or
|Filter Shade Number
|Gas Welding (Oxy)
|Less than 1/8, 3mm
1/8″ to 1/2″, 3 – 12mm
More than 1/2″ 12mm
4 or 5
(Shielded Metal Arc)
|Less than 5/32″ 4mm
5/32″ to 1/4″ 4 to 6mm
More than 1/4″ 6.4mm
( Gas metal arc)
Base metal – Non ferrous
Base metal ferrous
( Gas Tungsten arc )
Auto-darkening welding helmets.
Advanced welding helmet lenses are to be found on auto darkening helmets. the best of these offer variable controls that can be adjusted to suit the shade required. New technology using liquid crystal displays, (LCD) can darken the lens in milliseconds giving the welder utmost protection from the harmful welding rays.
The benefit of this type of helmet is that the welder is able to accurately see the area to be welded before striking an arc, as the lens is clear until the arc is struck. This not only is a more safer approach but also allows greater accuracy and neatness of the weld. This type of helmet is a must for continuous stop start welds used in production work, less stressful on the welder and more productive.
Choosing a Auto-Darkening Helmet.
Look first for comfort. Wearing a helmet all day is no fun if its overly heavy or has poor head mountings. Many new helmets can weigh only 18 to 21 ounces ( 602 grams , even with a full-coverage shell. Some models, with smaller view sizes and more compact shells, are approaching weights as low as 15-13 ounces.Next opt for full cover shells that will safely protect from sparks, grinding and weld splatter, also check that the helmet is capable of unexpected impact.
View size, there are several here with the larger being 3.82 x 2.44 inches (97x 62 mm) Most Auto Welding helmet lenses available have settings that can switch between between the different shade ranges, providing shades from 6 to 9 or 9 to 13. As a general rule heavy welds will require a higher shade lens as the currents are higher. For lower amperage work with MIG and TIG, you can use a lower shade lens so as the weld puddle remains easily visible.
More expensive welding helmet lenses will allow the user to control delay and sensitivity, depending on model, these controls can be either internally controlled or externally controlled.