Please choose the correct ending to complete the given sentence: Home and Garden: [header] How to tig weld [title] Put on safety gear. [step] Before operating any welding machine, make sure to put on protective eyewear, thick, fire-resistant clothing, and a welding helmet with an eye shield. [title] Connect the tig torch.

Ending1: [step] Connect the torch to the weld block. Note that the torch needs to be facing south when you have this connection, so that it will be able to catch fire if you're not careful. Ending2: [step] Run the welding unit at full power with the entire torch on. Once it is completely cool, connect the bolt you lift to the cast iron chamber you put in the workspace. Ending3: [step] This is a one-way operation that allows you to eventually turn away a flame at the iron outlet located at the very center of the technical machine. [title] Activate the power switch in the technical machine. Ending4: [step] All tig torches have a ceramic nozzle for directing argon, a copper sleeve for holding an electrode, and some way of cooling themselves. Use the adapter from your accessory package to plug the torch into the front of your machine.

Answer format: ending1/ending2/ending3/ending4