Alternatives to isopropyl alcohol?

[swaz]

Completely wrong (except for the PVC pipe prep bit) wrt commercial brake cleaner formulation!!!

None of them use acetone for the reason Chops gave.

They are mixtures with any or all of: alcohol, benzene, low boiling point alkanes (typically hexane), tetrachloroethylene.

eg. http://www.crcindustries.com/faxdocs/msds/5089.pdf

As has been noted, these solvent mixtures are more effective overall for brake cleaning than just a single component solvent like alcohol. Especially for mineral oil and grease.

You sound like you know your stuff. Riddle me this if you can please.
How exactly do these 'cleaners' aka solvents work if just spraying on a surface without any manual wiping to remove the dissolved oil? Do they break down the oils into a different substance that can then vaporize? Or do they just act like other solvents and bring the oil into suspension to they can be wiped/washed off.

 

[redbruce]

You sound like you know your stuff. Riddle me this if you can please.
How exactly do these 'cleaners' aka solvents work if just spraying on a surface without any manual wiping to remove the dissolved oil? Do they break down the oils into a different substance that can then vaporize? Or do they just act like other solvents and bring the oil into suspension to they can be wiped/washed off.

The latter (although dissolution rather than suspension), hence SummitFever's comment in post #37.

By contrast, alkaline oven cleaners (most effective remains the caustic based ones) actually break down the grease through chemical reaction (transformation into another more easily removed compound, typically a "soap" through saponification, that can be washed off with water). Caustic cleaners are still heavily used in industry for degreasing for that reason.

 

[swaz]

The latter (although dissolution rather than suspension), hence SummitFever's comment in post #37.

Thought as much. It's also the only post I didn't really read that well. I do hear/read lots of people comment that it is just a matter of spraying it on and job done.

 

[redbruce]

Thought as much. It's also the only post I didn't really read that well. I do hear/read lots of people comment that it is just a matter of spraying it on and job done.

A general rule for dissolution is like dissolves like (we used to use clean motor oil to help wash heavy grease of our hands prior to soap and water back in the day to help prevent hands drying out from too much washing).

Brake cleaners are miscible with water so the same principle of dissolve then wash with water can apply. Depends on what you're trying to remove.

Dot fluids (but not 5 - silicone based) are hygroscopic, that is they absorb water and so to a degree will be solvated in water. Brake cleaner, or an alcohol just helps the process along.

Mineral oil fluids and grease generally are not hygroscopic and need more volume of cleaner applied to effect adequate cleaning.

 

[si618]

FWIW, I used this link to track some IPA down for a decent price, unlike the bunnings rip off.

 

[The_Taurean]

Has anyone tried Prepsol / wax and grease remover? It should be perfect for the job and, being designed for surface prep before painting, it shouldn't leave any residue.

 

[redbruce]

Has anyone tried Prepsol / wax and grease remover? It should be perfect for the job and, being designed for surface prep before painting, it shouldn't leave any residue.

I haven't used it but it is designed to dissolve wax (but a range of organics by default) and therefore uses much less volatile components so it doesn't just flash off the surface before the wax has dissolved.

Formulation tends to be mostly Xylene, often with forms of benzene (not the best to breathe in) so generally more hazardous than other options (eg iso propyl alcohol).