I've previously discussed de-rusting solutions with others on here (which are mostly phosphoric acid based) and vitreous enamel, with the conclusion that the enamel should be unaffected (quite a reasonable conclusion). I've had two bad experiences recently, one a Tilley PL53 hood which was checked every 1/4 hr when dunked - all was well until the final 1/4 hr when the brown started to lighten in patches. The latest was with a Bialaddin 300X hood top (I'd gotten a new one so wasn't worried). This is the result... The enamel has also started to go powdery. Beware if you have an enameled hood that you want to keep and also de-rust!
I've also not yet found a way to remove rust from enameled vents. I just polish them with steel wool and Autosol and use them as they are. Even washing in soapy water causes already damaged or loose enamel to splinter off when it gets hot again.
When water gets under enamel and then is heated,it turns to steam with dramatic effect and can be very dangerous . If you must wash enamelled items put them into a warm oven to dry them out.
Yes, moisture underneath causes amusing "pings" of hot ceramic but the surprise was the effect on the actual ceramic of the solution. What I have done successfully with several hoods is to dab treatment (neat) on the rusty bits and then fire 'er up. Heat gets the reaction moving quicker and gets shot of any moisture content toot-de-sweet. Then clean off afterwards (when cool!) with panel wipe & spray with clear VHT.
I've had good luck de-rusting vents in a non-acidic rust remover like Evap-O-Rust. It is a chelating agent rather than an acid. I fill a plastic container with enough solution to submerge the vent, cover the container and let it soak for a while. I've left vents soaking for over two weeks with no noticeable ill effects. I tend to stay away from acids or extremely caustic solutions because things can go wrong quickly with them. I've found success by working from the least aggressive methods first.
...Tried to find the meaning of 'Chelating Agent' and I did , but not in a form I could understand? Could someone explain in simple terms what it is and how it works please???... ..A multi dentate ligand is not in my opinion a reasonable explanation as you then have to find out what exactly does that mean?...FFS.. Many thanks, PB
The idea is that the molecule is shaped in such a way as to "pick up" and hold a particular molecule so it can be removed in solution. That's as simplistic as I can make it
...Sorry HD, still far too complicated... ...Expat....I can cope with that...but is that stuff safe to put down the sink?... ...How do you dispose of it?
The Evap-O-Rust? According to the Data Sheets, you can use it repeatedly until it stops working effectively and then you can safely dispose of it down the drain. It's a proprietary solution, so only they know exactly what the agent is, but it seems fairly benign. I was suspecting it to be based on EDTA or our old friend Oxalic Acid but it states it 'contains no acids or alkalis', must be unicorn tears.
My father, an organic chemist, amongst other things, would be spinning in his grave at that! Breath in, breath out, chelation in action! Well, sort of!
Except that there is no binding going on there I know it's not a good explanation but it's not always easy to reduce the concept to a short explanation
