In Reply to: How do tell which grade Aluminum you are welding? posted by Tony on 12/20/01 at 11:28 PM:
That's the repair biz Tony. Knowing exactly what grade or type of material is often a luxury you don't have. With experience you will have some idea based on what the part is, or does.
Some metals will also be changed by the service environment. They will absorb contaminants or be physically changed by thermal cycling for example.
Many repair welding alloys are formulated to ovecome some of the hurdles encountered in repair situations. Some alloys are low temp to aid in the repair of thin materials or to enable you to repair something that would require equipment you don't have, such as a TIG machine. Other alloys offer an affinity to unlike or dissimilar grades of Al and other metals. Some are designed to enhance or improve performance via surface engineering. If I can help you on a case by case basis you can contact me any time. That's what we're here for.