Obviously welding helmets are a must for any type of welding, however not all welding helmets and lenses are equal. Different welding processes will emit different qualities of light brightness and because of this we require a welding lens to suit the work being welded.
Generally for a fixed welding mask lenses are available in various shades, the industry standard offers welding lenses in shades from 9 to 13, 9 being the lightest and 13 being the darkest shade. If you were to weld using a mig welder of around 175 Amps for example the weld lens used would be most likely a shade 9 or 10. Should you be doing heavy work using a high powered welder of say 400 amps then a lens of 11 to 13 would be the best choice.
Tig welders also emit brighter arc than a mig and would require a darker lens than you would use on a mig welder. In most cases the choice of welding lens is a matter of personal choice, on one hand you will need good visibility of your weld to see where you are going thus using a lighter lens, but you also need to protect your eyes with the darkest welding lens possible. Having a darker lens will cause less eye stress over a long welding period.
Auto Darkening Welding Helmets and Lenses.
Auto darkening welding helmets are a great innovation and will boost the productivity of any welding job, give the operator better control over the work and reduce the possibility of any arc flash. Auto darkening lenses are available on their own or with a complete welding helmet assembly.
Whenever shopping to find a new welder helmet the superior the quality the better the eye protection will be. A number of the less expensive varieties of auto darkening helmets and lenses possess a reduced darkening response period with the darkening in the lens whenever a welding arc is begun, even though it might seem instantaneous that your lens darkens there are actually micro second delays with certain low cost auto darkening lenses.
Lenses are also available in glass or plastic, glass lenses are the better option as they will not contain any color variations or distortions that may be found in a cheaper plastic lens. An auto darkening welding lens can be found as manually adjustable or automatic in the shade protection level. The best advise here is to buy a reputable brand and the best quality you can afford, you only have one pair of eyes.
Clear Welding Lenses
Always be sure to keep stock of the clear lens that protects the main welding lens, these are cheap and will become opaque, scratched and pitted from general use and weld sparks. This in turn over time will reduce your vision of the welding and may cause inaccurate or faulty welding.
Another innovation for welding helmets and the welding lens is the introduction of magnifying welding lenses. Typically sold in similar strengths as you can expect to buy when buying reading glasses of the shelf. For anyone who needs reading glasses a magnifier lens will be godsend.