No oil wanted/needed

[DavidR8]

^^ only non-chlorinated brake cleaner

 

[RJSakowski]

For degreasing parts, I prefer to use a petroleum solvent. Gasoline is my choice as it is highly effective, it is relatively low cost, and it fries off nicely. There are obvious restrictions, such as working outside and being aware of fire hazzard but it cuts grease well. As an alternative, kerosene will do nearly as well and isn't as flammable. Mineral spirits also work well. After I have removed all the oil or grease then I would follow with an acetone rinse, blowing any residue off with compressed air.

 

[Bone Head]

Thank you all; I will report back.

 

[Nutfarmer]

Dawn by its self should not bother aluminum. I wash aluminum pots and pans in it. It will cut grease. High pressure sprayer is my go to for all the grease and dirt around the farm.

 

[Bone Head]

Your pots and pans are not pourous. This case is cast from fairly cheap stuff, it is.

 

[Eddyde]

Dawn, or any dish detergent alone will not harm aluminum and with hot water will do a fairly good job of cleaning it.
For more stubborn, dried on grease, I like to use Zep, Citrus Degreaser, usually available at the big box stores. I have used it many times on aluminum, without any issues. I give a final rinse in Acetone if its going to be TIGed

 

[woodchucker]

Simple Green Pro works well and doesn't hurt aluminum. If possible, I'd put the case in a large tub and boil the thing on your BBQ for an hour or so. As a pre welding step, acetone, carb cleaner, brake cleaner, something nasty and harsh to get any remnant oil out. There will still be oil in the porosity of the aluminum, and your welder may cuss you for it. But at least you will have done an honest job of minimizing his agony.

and possibly killing him.. NO to BRAKE CLEANER..
Acetone is probably the least harmful... Where's @pontiac428 when you need him.

 

[pontiac428]

Where's @pontiac428 when you need him.

Snoring and drooling on the west coast, of course!

I've read where Simple Green and Dawn dish soap will attack aluminum.

Dish soap would be my first choice in your case, followed by abrasive prep at the weld site.

As we know, aluminum oxidizes and forms a tight boundary layer that is different from the metallic aluminum base. That aluminum oxide pulls hydroxides (from water vapor) close to it to form a complex aluminum oxide hydroxide. Simple Purple, et. al., has a hydroxide (alcohol) at both ends that are highly attracted to the oxide layer and bind tight. It changes the way light reflects from the surface causing it to appear dark or stained. Polished aluminum doesn't stain, I only see it with freshly blasted or cleaned aluminum. Eventually, the stain fades as the cleaner breaks down, but it can be disconcerting.

After dish soap, acetone is convenient for weld prep because it evaporates quickly leaving less contamination in your weld zone. Alternatively, just rough up the surface with a new, stainless bristle wire brush, or a piece of emery cloth after degreasing and prior to welding.

 

[francist]

Eventually, the stain fades as the cleaner breaks down, but it can be disconcerting.

So what we have assumed was “etching” of the surface is really just a stain that will eventually fade away? Am I reading that correctly?

 

[B2]

Gasoline, followed by naphtha followed by acetone to get the bulk off and then followed by hot (boiling it would even be ok) Alconox (soapy) water then rinse it really well with clean water. Dry between each step. Each of these organic solvents takes off different stuff. I sometimes mix acetone and Toluene, 50:50, for removing some polymers. You may need to let some of them soak.

My dad was a rural area letter carrier and some times they would oil the roads, spread gravel, oil them again, etc to make a layered surface (asphalt on site). Of course he had to drive in it to get to the mail boxes. So when the roads were done we would clean the car off. It would commonly be black all the way up to the windows and even on the windows. Of course embedded in this oil was dirt/dust/'gravel from unpaved roads making the coating pretty tough. You could not just rub it or the paint would scratch. So, we used a Hudson sprayer to apply kerosene and let it soak/run off. The oil would run down the car sides and drip. We then sometimes used naphtha (lighter fluid) to spot it but more commonly we just went at it with hot soapy water. No wax left on the car either! Then there was a near by low water creek which we could drive into, park on the river gravel bottom with the water level just below the door openings. More soapy water and then a rinse.