Today's video is about Tig welding aluminum parts. 7 small assemblies to be exact.
From what I could find out, these parts will be used as sort of a pry bar to disassemble some sort of precision, high cost machine.
The parts are made from 6061 t6 aluminum so that it will be softer than whatever metal it is against...and so that it will give or break before it damages the part it is removing.
There are only 3 pieces to weld together and my machinist customer even made a quick fixture to align the part for welding.
That's one thing I like about doing work for machine shops is that they will often make a fixture for you to make sure the parts come out straight.
Tig welding small aluminum parts like this is gravy. All I have to do is assemble and weld.
Normally, this job would have gone better.... I should have cleaned the parts better.
These parts arrived unexpectedly, and actually interrupted another job I had going..A plasma cutting table.
... so I just gave them a quick wipe down with some acetone. I should have soaked them in acetone or some kind of degreaser along with an aluminum cleaner. They should have welded a lot cleaner..and they would have... if I had done my job better.
Speaking of cleaning aluminum, What kind of aluminum cleaner works best?
Well , there are cleaners specifically designed for welding like
Weld-O Preweld Aluminum Cleaner from Harris.
Weld-O is an acid based cleaner with other solvents added and is advertised to provide a prep suitable for x-ray quality welds.The problem is it had hydrofluoric acid in it and that stuff scares the crap out of me. Even though its only about 6% HF acid, that is enough to make me wary.
There are other cleaners that dont use acid but rather use an alkaline mixture that removes the surface oxides.
one example called "Aluminum Etch" is available from Stoody Industrial.
I have heard of folks using plain old "purple power" also...its an household alkaline cleaner/degreaser that will etch aluminum and needs to be rinsed off with water or it will cause corrosion.
At the Sun N Fun event I attended recently, I spoke with a fellow who swears by "Easy Off " oven cleaner for cleaning prior to tig welding aluminum parts that are very dirty or have been exposed to the elements for a long time..
I have not tried it yet , but I will. It makes sense too because sodium hydroxide is the active ingredient and that will definitely etch aluminum.
The next time I am tig welding aluminum I am going to try the Easy Off cleaner and let you know how it works.