We are working with acids here. Not only can they burn, they can create noxious fumes as well.
It is sensible to wear eye protection, waterproof gloves and do it all outside.
If you are spraying the inside of your headlights to make them look like Brabus ones or just to make them look nicer, you could sit there with wet and dry sandpaper and try and get in all the small grooves, however, this takes ages. The other option is to throw it into a bucket of acid and let that strip the metal from the plastic.
Yeah. It's using the same method patented over 100 years ago by a British engineer to etch printed circuit boards.
It etches the copper from the fibreglass board and just leaves the copper that you want to become the tracks.
Luckily enough, this method also attacks chrome plating and removes it in the same way.
By far the cheapest and safest way to strip the chrome from your headlights. It's a trick used on old cars.
I never got a chance to try it as I had the stuff for the other 2 options. Why would I have oven cleaner?
Clive M tried it out and it worked well. The oven cleaner is cheap and easy to buy so I got some.
Here are the chrome inserts I removed from the headlights.
And this is the oven cleaner I used. Check the info, it needs to contain sodium hydroxide.
Spray it on all over the headlight insert and leave it. This stuff foams up and doesn't need any scrubbing.
I did it outside but you can put them on an oven tray and that'd get cleaned at the same time.
After 15 minutes I wiped a bit away with my finger and the chrome seemed to be gone (my skin stayed).
So I rinsed the oven cleaner off and they were chrome free.
Dry them off with a towel and a hair dryer.
Then you can prime them for painting.
No super horrible chemicals required.
This option is using the age old PCB etchant ferric chloride. It smells, it stains.
However, it only etches what it touches and it's not as dangerous as option 3.
Ferric chloride can be bought from electronic supplies store online. Generally it comes in a bag of dry lumps.
You just have to mix it with the appropriate amount of water in a plastic bowl.
Dip the piece in that you want to remove the chrome from.
And leave it. Below was after a few hours. You can see it has started eating the chrome.
After a few more hours it's evident that the process is working. This will not affect the plastic underneath.
The next day, all of the chrome underneath the ferric chloride solution will be gone.
Not as dangerous as other methods.
You can selectively etch chrome from certain areas.
Easy to buy from electronics stores.
Ideally the piece should be moved a lot to increase the etching speed.
You need to totally submerge the piece to remove all the chrome.
Expensive if you need to fill a bowl for full piece etching.
And now the far quicker, cheaper, easier and more dangerous way.