Darkening cast iron?

[Brian Holcombe]

I use something similar to what Steve uses; brass black. For some reason it works well on iron.

[dennis davidson]

Second the linseed/flaxseed oil. Turns grey cast iron nice and black after heating in the oven.

[John E. Braun]

These guys make something that should help : https://jaxchemical.com/shop/jax-iro...kel-blackener/ I have not used the product for cast iron, but have used their bronze darkener to good effect for years.

John

[Kevin Perez]

Be careful using cold blue (gun blue). It can leave a smell on the metal that doesn’t go away. I used it on an old Opinel knife just for kicks, and while it looks great, it has a smell that gets on my hands when I touch it. The smell lasts for months and months (on the metal, not my hands...).

[Derek Cohen]

if you want to keep it raw and keep it from rusting, I would suggest seasoning them with unrefined linseed oil, and if they are food grade, unrefined flax seed oil. clean with something strong to remove all residue, use a rag and rub on a light coat of oil, put in cold oven and set for 500 for an hour after it gets to temperature. after the hour, let it cool and repeat. I do 4 or 5 cycles on raw cast and when re seasoning my pans I do a couple coats after a vigorous scrubbing with chain-mail scrubbie and salt. it should turn out a beautiful matte black.

flax and linseed are the same thing. one is generally processed on food grade equipment and the other is not. very low smoke point so the oil will polymerize. refined oil has a much higher smoke point.

Thanks Adam. I will look into this.

Regards from Perth

Derek

[Derek Cohen]

"Wipe on, wipe off."
Attachment 389428
What I use to bring out an etch.

Steven , this brand is the only bluing chemical available in Australia. Does it turn the iron black or black with a blue sheen?

Regards from Perth

Derek

[steven c newman]

Black. Haven't noticed any blue tint.

[Derek Cohen]

Thanks Steven.

Regards from Perth

Derek

[Jeff Ranck]

Wow! Who knew that these were so many ways to darken cast iron.

[lowell holmes]

Propane torch might darken the Cast Iron.

[Derek Cohen]

Here's where I am at this stage:

I have cast iron knobs for the chest I am building. The are silver-light grey in colour. I would like them to be charcoal-to-black.

The issue with cold bluing formulations is that they create a finish that wears with handling. Drawer knobs get handled frequently (although these should not get daily use).

Hot formulations are more durable than cold formulations. I have a good friend who is clued up on the chemistry of these products. I mentioned that I had ordered a stove polish. This is rubbed on and then the iron/stove is heated. Lots of smoke issue, and then the finish gets rubbed back. He said that this is equivalent to the hot formulation, and should be durable.

This is the product I have ordered ...

https://www.rubbedin.com.au/Product/...horizontalTab1

I ordered one extra knob, and will experiment on that when the polish arrives.

Regards from Perth

Derek

[Derek Cohen]

Here's where I am at this stage:

I have cast iron knobs for the chest I am building. The are silver-light grey in colour. I would like them to be charcoal-to-black.

The issue with cold bluing formulations is that they create a finish that wears with handling. Drawer knobs get handled frequently (although these should not get daily use).

Hot formulations are more durable than cold formulations. I have a good friend who is clued up on the chemistry of these products. I mentioned that I had ordered a stove polish. This is rubbed on and then the iron/stove is heated. Lots of smoke issue, and then the finish gets rubbed back. He said that this is equivalent to the hot formulation, and should be durable.

This is the product I have ordered ...

https://www.rubbedin.com.au/Product/...horizontalTab1

I ordered one extra knob, and will experiment on that when the polish arrives.

Regards from Perth

Derek

[lowell holmes]

Not sure about cast iron, but I do that with steel. Heat it up and then put BLO on it while still hot. Turns it a nice dark gray.

Did you ever look at the bottom of a cast iron skillet. They are certainly black.

[Bill Orbine]

I'll put aside my joking around and suggest that you Google "Black Magic Patina". You are looking for Sculpt Nouveau. This is a product I had forgotten till I saw my friend's blacken tin mantle shelf.

[matteo furbacchione]

I wonder if the cast iron would darken if heated with a torch?

Yup, but you need to add an oil based product (I.e.e wax) to the hot iron, and then it goes black. The wax/oil needs to be cooked into the iron so the metal needs to be fairly hot. Well past the point where wax boils but not red hot.