Final answer:
Using too large a torch tip in oxyacetylene welding can result in a yellow, feather-like flame and poor welding performance. It can also cause damage to the metal being welded and create safety hazards.
Step-by-step explanation:
When using an oxyacetylene welding torch, using too large a torch tip can be indicated by the presence of a long, yellow, feather-like flame. This indicates an excessive amount of acetylene gas being burned compared to the oxygen, which can result in an unbalanced flame and poor welding performance. Additionally, using too large a torch tip can lead to excessive heat buildup, causing damage to the metal being welded and potentially creating safety hazards.