Sandblasting

Yes, depending on the application and for ferrous metals, 'Deox-C.'.

Make up yer quantity, pop the bits in, take them out and rinse and dry them and get them protected again asap. ;-)

That said, I have always wanted a decent shot plastic cabinet but they are big, need a big compressor, really need good extraction and are quite expensive to run (media / screens / gloves / filters / electric).

Cheers, T i m

Builders' sand is too soft and damp. Play sand - also used between paving blocks- may work but I'm not sure. I tends to be dry and 'hard'. I'd expect to need a good air pressure to make it effective.

You can buy the proper stuff on Ebay.

Have a look on Youtube, I'm sure I've seen some DIY sandblasting videos.

Think no one size fits all - and it also depends on the item you're cleaning. With, say, an external panel on a car you'd not want to damage the good parts of it. With a casting, etc, it may not matter.

Sadly some of the better materials for just removing rust without doing further damage are also more expensive than sand.

If the bits are small enough, stick them in the dishwasher when the missus isn't looking :-)

Hmmm. I'm not really sure what this product could do that Hydrochloric acid (at a fraction of the price) couldn't do. In fact you'll probably find that it's made mostly out of HCl with some inert thickening/ colouring agent (like Jenolite).

Jenolite is made with (ortho)phosphoric acid.

SteveW

The difference is that sandblasting will take off paint and other surface coatings (like blueing or chemical blacking) getting you back to essentially clean metal. (Yes I know that it isn't clean at the atomic level).

I'm just wondering if sandblasting damages rubber gators, oil seals etc? I'd like to get my brake calipers blasted but am concerned about such damage. Anyone know?

Yes, they will be damaged, and the caliper may become scrap.

you strip everything off and out of the caliper and mask areas that should not be touched, such as the piston bores, after the blasting you clean, using solvent, brush and compressed air.

Allow you to put your hands in it and be easily disposable? ;-)

Well, it's completely liquid (like water) and clear so I'm not sure.

All I know is you make up say 25l of the stuff, drop what you want de-rusted into it, leave it a while (depending on the level of rusting) rinse it off and paint it (quickly!). ;-)

When you are done with it, you tip it down the drain.

Cheers, T i m

Depends how much it costs, then, since the nearest alternative to that I know of is electrolysis: mix up a bucket of sodium bicarbonate solution and attach a battery charger to the rusty part. Takes about 10 hours all told then chuck the used soln away. Bicarb is cheap as chips!

Yup, I have a rig for that as well but I don't think it's as good or safe as using Deox-C. For example, you have to be very careful what metals you use for electrolysis cleaning because of the chemicals and gasses it can produce.

Cheers, T i m

Or (Hydrogen) embrittlement even. ;-)

You had me worried for a minute there; thought you'd hacked into my medical records online! :-D

The MSDS shows it is a weak organic acid (perhaps more than one). The quoted melting point of 211 C is close to that of sulphamic acid (205 C).

Hehe!

Cheers, T i m

I think people also use citrus, or possibly citric acid so would that make sense from what you said? Could that be what the 'C' stands for in Deox-C?

A mate, doing lots of repairs on old vehicles put me onto Deox-C and I have used since it quite a bit to very good effect. Completely rusted up trailer brake drums came out completely free of rust, similar with smaller trailer wheels and anything else that I found that was heavily rusted and would fit in the plastic drum.

I tied de-rusting a cheap panel saw and left it in there for quite some time (days) to see what would happen. It came out perfectly de-rusted but as floppy as a sheet of A4. ;-)

I would say it was definitely ideal for detailed ornamental stuff as it saves all the wire brushing and there is no real issue re any changes to the structural strength (see the saw example above). That said, I'd also happily use it on 'mechanical things' but might keep a closer watch on the immersion time etc.

Cheers, T i m

People I know that use it don't dunk parts in it. They are doing car under-bodies. They paint it on and then cover with cling film.

Yes, they do a liquid 'dunking' type and the gel you mention the use of that suits bigger parts (like cars or gates).

Cheers, T i m