TIG cup selection - Part 1
Since the early days of TIG, the standard selection of cups have been set. Even gas lens cups have been around a while now. The question remains though: Do I need to spend the extra money to get one? The simple answer is yes. Gas lens offer you the capability to improve the overall appearance and quality of the weld in many situations where gas coverage can be spotty or inconsistent. However, there are times where a gas lens may not be that beneficial, such as running a TIG root deep inside a V groove, where gas can settle around the weld without much disturbance. The smaller diameter nozzle would allow you to get deep down into the groove, minimizing stick out, and improve your ability to “walk the cup”. A larger diameter nozzle, even the smallest gas lens might prevent this in running a root on pipe. But in most circumstances, a gas lens will offer superior results, particularly in drafty shops or large opens spaces. Recently popularized, new types of gas lens and gas contraptions are being marketed such as titanium or Pyrex cups, and trailing attachments. These do offer their advantages, but the price jumps significantly to purchase and maintain these. Pyrex can easily shatter and the trailing attachments can get damaged. Don’t forget titanium is very expensive. If you are going to purchase a gas lens, try to do it in a kit with standard alumina (pink) nozzles before you get too exotic with your preferences. You will always find some way to damage them and alumina offers the best choice in durability, economy and replacement.