Cold blueing

[edbear2]

This one?

https://www.sotel.de/en/Werkzeug-Gar...ur=1&shipto=GB

I have used all sorts, and as Jerry says degreasing is key, acetone or sometime in the past trike / similar industrial cleaners seem to work well, plus a bit of heat, and also I have found applying with fine wire wool sometimes works.

It's all down to messing around and experimenting and to some extent the base metal itself, a few years ago a pro rebluing place was driven mad trying to blue a Lothar barrel blank I sent them to match a TX action they were doing in the same tank at the same time.

Took several goes before it came out right!

ATB, Ed

[stevegv8]

https://ballistol.co.uk/products/bal...39852136497334

https://www.uttings.co.uk/p103728-ballistol-oil/

Aren't these just oils?
Going to give G96 a trial

[Hartcliffer]

Aren't these just oils?
Going to give G96 a trial

I think he meant this one:

https://ballistol.co.uk/products/quick-blueing

[gingernut]

Even I get good results with G96

[ccdjg]

I have had to degrease steel and aluminium on several occasions prior to bluing, anodising, resist application etc., and the industrial standard for a fully degreased surface is that when you put water onto it, the water spreads thinly over the whole metal and doesn't pool into patches.

This could be very frustrating, as sometimes I could try my hardest, with acetone, or methylene chloride, and/ or vigorous rubbing with (degreased) steel wool and washing up liquid, and it just wouldn't pass the water test; other times (very rarely) it would work first time. Then I found the answer. Finish your normal degreasing sequence by scrubbing with degreased steel wool and sodium carbonate powder (washing soda), ( anhydrous, dirt cheap off Fleabay) made into a thick paste. Do this under running water until the surface wets fully. Use latex gloves to avoid touching the surface during this stage. This has always worked for me.

(The alkaline nature of the sodium carbonate simulates what the traditional gun bluers used to use for degreasing - scrubbing with lime.)

[Benelli B76]

I have cold blued hundreds of airguns and firearms. I simply rub the surface over with a clean cloth containing cellulose thinners, then apply G96 Gun Creme. After a minute or two wash the surface with water to stop the blueing process, and wipe over with oil. Some harder steels I warm slightly until the metal "sweats" and moisture appears on the surface, then wipe it with a clean cloth before blueing. This takes very little heat to take place and the metal should not be hot as the G96 will dry into a powder. Doing this way the metal should only be slightly warm to the touch. I have just blued some rifles and I never used any chemicals to degrease, just blued them straight after linishing off the rusty surface.

Baz

[Jerry Cornelius]

I’m not entirely sure how you can get good results without degreasing, although I’m not arguing with your experience, unless your preheating (which must be with a flame if you are seeing water deposited on the metal) is burning off any oil and grease.

[jirushi]

May I ask how people remove old blueing?
I have used Birchwood Casey Blue and Rust remover, but the smell is horrible, even in a well ventilated room.
I've heard that vinegar works.

[Jerry Cornelius]

May I ask how people remove old blueing?
I have used Birchwood Casey Blue and Rust remover, but the smell is horrible, even in a well ventilated room.
I've heard that vinegar works.

Fine wire wool, oil, and elbow grease in my case

The only chemical treatment I use is rust converter if there is pitting.

You’re going to have to polish anyway so I can’t see a benefit in trying chemical removal?

[wil95k]

May I ask how people remove old blueing?
I have used Birchwood Casey Blue and Rust remover, but the smell is horrible, even in a well ventilated room.
I've heard that vinegar works.

White vineger works.Degrease the parts,then submerge in vinegar.

[steviebee]

Hi .
Do you guys fully strip the metal work down to the bare metal like you would do for traditional hot blueing?
Cheers

[Jerry Cornelius]

Hi .
Do you guys fully strip the metal work down to the bare metal like you would do for traditional hot blueing?
Cheers

I do, anyway. Imho the quality of the finish is more or less entirely dictated by the quality of the prep. I’m sure if you started with a partly blued item the cold bluing would never be uniform

It’s not great stuff.

[jirushi]

I have had to degrease steel and aluminium on several occasions prior to bluing, anodising, resist application etc., and the industrial standard for a fully degreased surface is that when you put water onto it, the water spreads thinly over the whole metal and doesn't pool into patches.

This could be very frustrating, as sometimes I could try my hardest, with acetone, or methylene chloride, and/ or vigorous rubbing with (degreased) steel wool and washing up liquid, and it just wouldn't pass the water test; other times (very rarely) it would work first time. Then I found the answer. Finish your normal degreasing sequence by scrubbing with degreased steel wool and sodium carbonate powder (washing soda), ( anhydrous, dirt cheap off Fleabay) made into a thick paste. Do this under running water until the surface wets fully. Use latex gloves to avoid touching the surface during this stage. This has always worked for me.

(The alkaline nature of the sodium carbonate simulates what the traditional gun bluers used to use for degreasing - scrubbing with lime.)

Great advice, thank you.
Put into practice on Sunday and yesterday evening, in my little kitchen.
I checked the quality of my degreasing: the water would not pool into patches.
I did not do this check with the cylinder, and I also did not use sodium carbonate on the cylinder.
The cylinder turns out to be the least neat part, so I think I know what to do in the future.
I used vinegar and Birchwood Casey Blue and Rust Remover to remove the old blueing.
The Birchwood Casey stuff works better and faster, but it smells really toxic. I only use it outdoors.
For degreasing and blueing, I used swabs. That worked well.

[junglie]

I know refinishing is frowned on (by me too) and most cold blues are a bit hit and miss, but in case anyone is interested I think I got some ok results with Phillips Professional Cold blue:







And before:







In my defence I think tatty enough to make a refinish justifiable

Obviously not as good as hot blue but not too bad I think

My two learnings were (1) acetone for degreasing and (2) check the blueing solution carefully for the rear sight riser screw before you pour it down the storm drain. Unless you enjoy spending an hour going through the silt trap with a magnet of course

Nice job, I have a magnet on a telescopic handle for that very job......Although the thought of it always reminds me of uncle jack from ripping yarns "curse of the claw"

[Mr wobble]

Would car brake cleaner be a good enough degreaser?