Cold bluing wrought iron

[Joël Mercier]

I did a quick google Fu and found nothing. Anyone here tried? If so, does it make the grain pop? Darken the wrought much?

 

Thank you gentlemen 

[Joshua States]

I've done it.

Before bluing

 

 

After bluing

 

 

 

I have to say, my cold bluing technique is atypical. I don't just apply it to the piece. I apply it hot, like around 150-200F, wipe off the excess with a paper towel and bake it for 10 minutes. Repeat.

[Joël Mercier]

That is an interesting finish. On top of your own technique, which product are you using?

[Joshua States]

30 minutes ago, Joël Mercier said:

That is an interesting finish. On top of your own technique, which product are you using?

Birchwood Casey cold blue paste. Not the liquid. It comes in a tube.

These pieces were also etched in ferric before bluing. That brings the grain up.

[Jeff Amundson]

This scissors is rust blued wrought iron, sitting on the bar it came from. I probably etched it in ferric before bluing. The parts get boiled to blacken the rust, so I don't know if it qualifies as cold bluing.

[Joël Mercier]

8 hours ago, Joshua States said:

Birchwood Casey cold blue paste. Not the liquid. It comes in a tube.

These pieces were also etched in ferric before bluing. That brings the grain up.

Okay, I've got Brownells oxpho blue liquid. It normally does a fine job on steel, but I don't know on wrought. I will try etching in ferric first, thanks!

 

6 hours ago, Jeff Amundson said:

so I don't know if it qualifies as cold bluing.

I believe it doesn't. Very beautiful piece nonetheless!

[Joël Mercier]

My wrought seems cleaner. I did several ferric cycles with steel wool cleaning in between and a cold blue. I am not entirely satisfied, but this will be it. 

 

 

[Gary LT]

Joel, I’ve had on hand two wrought iron bundles and one is more refined wrought as in this knife pictured.

You can let it sit in ferric longer than you’d think, can’t tell you how long but just keep it in an check it as you go. My other bundle does really nice topography

Ive used Birchwood Casey before, more recently Vans, (which I liked) and I just started Mark Lee’s Express Blue, still experimenting though, as the directions are quite detailed to produce the equivalent of hot blue.
Gary LT

 

Edited December 5, 2022 by Gary LT
Add 2nd photo

[Joshua States]

On 12/4/2022 at 5:01 PM, Joël Mercier said:

I did several ferric cycles

Time in the etch? Do you agitate the ferric?

[Joël Mercier]

19 minutes ago, Joshua States said:

Time in the etch? Do you agitate the ferric?

5 minutes x3 and no agitation. 

Edited December 8, 2022 by Joël Mercier

[Bill Schmalhofer]

On 12/7/2022 at 9:30 PM, Joël Mercier said:

5 minutes x3 and no agitation. 

I'm going to chime in on this in proxy for @Joshua States (sorry Josh...). Agitate the ferric. It makes a HUGE difference. Use a aquarium air pump. Piece of long tubing on the pump to send  the air down to the bottom of your ferric tank. I haven't noticed much of a difference if a diffuser stone is used or not. I also put a piece of wire in the tube to make sure the end stays down at the bottom as I kept having issues with it floating to the top. Full credit for this idea goes to Joshua.

[Joël Mercier]

Good to know, thank you both.

Edited December 12, 2022 by Joël Mercier

[Gilbert McCann]

Not to do with bluing. I've had wrought that was pretty resistant to Ferric (with bubbles) but was affected by ph down (sodium bisufate). In that case I do time in both. 

[Joshua States]

11 hours ago, Bill Schmalhofer said:

I also put a piece of wire in the tube to make sure the end stays down at the bottom

I drilled a 1/4” hole in a chunk of 416 SS and pushed the hose through the hole. It’s a tight squeeze and the weight is impervious to the ferric

 

giving credit where  it is due, I learned this from the late Tim Hancock

Edited December 12, 2022 by Joshua States

[Joshua States]

On 12/7/2022 at 7:30 PM, Joël Mercier said:

5 minutes x3 and no agitation. 

I also tend to use slightly longer (8-10 minute) cycles

[Alan Longmire]

13 hours ago, Joshua States said:

I also tend to use slightly longer (8-10 minute) cycles

 

I use that for regular damascus.  For wrought I often do 30-minute cycles.  

[Brian Dougherty]

It is rare I say something like this on here, but initial concentration of the ferric, how old it is, how much it has been used, and shop temperature have a huge impact, and make the direct comparisons of etch times difficult. 

 

I think I recall a newcomer a couple of years that ago took one of us at face value with his brand new ferric solution in the summer time and etched the crap out of his blade.

Edited December 14, 2022 by Brian Dougherty

[Alan Longmire]

True, and thanks for pointing that out!  

 

But yeah, wrought usually takes longer than steel if etched side by side in the same tank.  

[Joshua States]

5 hours ago, Brian Dougherty said:

t is rare I say something like this on here, but initial concentration of the ferric, how old it is, how much it has been used, and shop temperature have a huge impact, and make the direct comparisons of etch times difficult. 

This is something we all tend to forget. Thanks for reminding us!