Gas Cups & Back Caps

Ceramic cups and back caps for TIG torches - the two consumables that set your shielding envelope and your working clearance.

Cup size is a trade you make per job

The cup number is its bore in sixteenths of an inch. A larger cup shields a wider area and is what aluminum and stainless want, because both punish any atmospheric contamination. A smaller cup gives access into corners and tight fillets that a large cup physically will not reach.

Alumina ceramic is the standard material: cheap, good thermal shock resistance, and it fails visibly by cracking rather than quietly.

Back caps are about clearance, not protection

The back cap seals the rear of the torch and covers the tungsten stub. Length is chosen by where you are working:

Long takes a full-length tungsten and needs room behind the torch. Fine at a bench.
Medium is the general compromise.
Short matters when you are working into a corner or against a wall, where a long cap fouls before the torch reaches the joint. Requires cutting tungsten shorter.

Keep a short cap in the drawer even if you never use one day to day. The job where you need it is the job where nothing else will do.