A lot of these spray-on so-called rust removers are advertised on Facebook. The adverts show the liquid being sprayed onto heavily rusted components such as Mac strut front suspension units and, as if by magic, all the rust falls off - revealing shiny metal underneath.
Surely, they can't possibly work?!
Look up chelating with citric acid. The rust does basically fall off, although a little agitation may be needed to move it away from the metal.
Evapo-rust is a magical (read: expensive) proprietary product, but it does the job. Edd China explains the chemistry of chelation in the first 5 minutes:
Citric acid is an aliphatic carboxylic acid, and sodium citrate is a salt of an aliphatic acid.
Theo
Although that doesn't explain where the sulphur in the iron sulphate comes from. Mass spec suggests it's triethanolamine phosphate plus aluminium sulphate:
and the datasheet shown in the video:
Water 55-65% Triethanolamine phosphate 20-30% Aluminium sulphate 1-5% Citric acid 1-5% Dipropylene glycol methyl ether 1-5%
but it's possible to make your own for less with ingredients from the kitchen:
^^^^^^^^^
I've highlighted the important clue above ...
all great info, thanks Theo!
Indeed - DIY rust remover from now on!
I object y'r honour! I've seen these ads on Youtube (owned by the sainted Google. (At least: "sainted" when compared to Meta). What's more, I was seeking to watch a youtube about painting my model of HMS Belfast -- a noble occupation I'm sure you'll agree.
I've never been near Facebook, except by accident, since I first saw it (at work in our computing department) since about 2005.
I love these adverts! It's like going down the old markets pre-1980s, and watching the salesmen selling **miraculous** this'es thats and the others. (And they made good sales, OK!)
Another John
Forget the commercial stuff, make yourself some of this:
This works very well in my experience.
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