Blueing

Surely the gunsmiths do browning

This method seems to produce very good results. The parts are put in hydrogen peroxide to make them rust quickly. And then they are boiled in water.

As in 'Brown Bess'*, yes. Before bluing, many firearms were 'browned'. Have to look up the exact process, but it consisted of repeatedly building up layers of fine rust and polishing them back to leave a protective brown covering.

In the usual way, the gun-trade became remarkably conservative, and insisted on calling any protective layer 'browning' for many decades after bluing had become dominant. In the same way, 'ball' ammunition has been cylinder-conoidal since about 1870.

Dave

* The origins of the name 'Brown Bess' are uncertain. The musket was obviously 'brown', but the nickname may have come from another friend of soldiers; at the time 'Brown Bess' was slang for a prostitute. Or vice-versa, the ladies were named after the gun.

To add to the confusion, browning as in bluing has nothing to do with the prolific gun inventor John Browning.

I used G96 cold blue 'creme' (fancy word, I'd call it a paste) on the naval cannon in my pic album, in 2005. It still looks the same now AFAICS, with one light touchup at some date in between.

Rust blueing is the process of producing rust then brushing it off (carding). The first few cycles won't leave much finish but about 6 cycles starts to produce a blue. A dozen or more makes the deep, hard, blue seen on old Mausers and such. Takes about a month minimum to produce that fine finish.

Rusting solutions vary and can be found in many old books on the subject.

Pete

The process of blueing/browning as practised for hundreds of years by gunsmiths is very simple, I've done it many times on shotgun barrels in the distant past. It can produce a fabuous finish but takes time and patience.

Browning and blueing is exactly the same process except for the boiling of the final product to change the colour. The item to be treated is first degreased then covered in a rust promoting liquid. This liquid can vary considerably and there are many old recipes that claim to be the best, most of them containing ingredients that would be very hard to obtain these days. the most common ingredient used would usually be copper sulphate along with various acids/nitrates/phosphates (and usually urine). In truth the same result can be obtained with plain old water - but it takes much longer. After coating with the rust promoter the item is placed aside in a damp environment for a few days to develop a coating of rust, most of which is then removed with wire wool. The process is then repeated numerous times until a deep and even coating of rust remains. If a brown finish is required it would then be washed, waxed and polished. If a blue or black finish is required then the item would be immersed in boiling water until the rust turns the required shade of blue, followed by waxing and polishing.

This old process can produce a superb and durable finish if properly done - but it can take weeks or months to develop a deep satin blue sheen.

This is a practical example of two different techniques, not recent I add. There is some wear, but it does illustrate the durability, albeit with the limitations of the photo reproduction

The one of the left  I made at school, I think in 1978 and was blued by heating and dipping in in old engine oil.

On the right was an apprentice piece, made in 1980 and phosphated using a commercial process.

Edited By Stuart Bridger on 30/03/2023 08:29:03

Edited By Stuart Bridger on 30/03/2023 08:30:57

Got my blueing and had a first attemp but i suspect the part was not properly degreased. Just wondering what people use to degrease? Could i use brake cleaner?

What method did you used in the end? How does it look like? Acetone is a nice non toxic degreaser and is widely available.

I used a wipe with meths followed by a hot wash in washing-up solution, then apply the bluing with a soft paintbrush while the metal's still hot. Wash again (in rubber gloves), dry, and oil up when happy.

Edited By Mick B1 on 31/03/2023 12:19:48

Yes, or acetone, or soapy water, perhaps in combination. Like glue, the secret of success is absolute cleanliness.

Things likely to spoil bluing:

• Steels that resist corrosion in any way, not just Stainless
• Steels that have already been treated - painted, phosphated, galvanised. These processes go deeper into the metal than might be expected, and have to be removed.
• Metal were the surface has already been damaged by corrosion, welding, folding, stamping, heat-treatment etc.
• Oil and grease are also hard to remove completely because they penetrate into microscopic cracks and crevices. At the molecular level even highly polished surfaces are full of ravines and caves that catch and hold dirt.
• Abrasive cleaning methods such as sandpaper or sand-blasting that tend to leave abrasive material stuck to the metal (in non-obvious microscopic quantities)
• Handling on a grubby bench with anything other than clean rubber gloves and clean grease-free paper or cloths.

So, depending on how dirty the item might be, and how important it is to guarantee a good finish:

1. Choose a steel that blues nicely
2. Sand-blast or surface grind to remove deep problems, then
3. Wire brush clean, followed by
4. Strong degreasing, maybe boiling in caustic soda solution, followed by
5. Water rinse to remove degreaser and muck, then
6. Acid wash & short soak (to remove any remaining degreaser, and neutralise alkalis, also flux and oxides if present), followed by
7. Hot water and detergent wash (to remove remaining grease), followed by
8. Deionised water rinse (to remove detergent and tap water contamination), then
9. Alcohol rinse (to remove water), then
10. Spray liberally with Brake Cleaner or similar, to deal with residual grease. As soon as dry proceed quickly to the bluing process
11. Apply a reliable bluing process, and practice it first

Most of the above is optional. I don't attempt pretty bluing, or care if results are uneven and blotchy. I wipe off the worst with clean kitchen towel, check to see how grubby it was repeating as necessary, and if OK I wipe again with the towel soaked in brake or carb cleaner, then a quick spray to finish off. (Rubbing tends to leave fibres struck to the metal.)

Rough stuff mostly in my workshop. I'm more likely to splash phosphate on rust than do a proper job. However, I'd throw the book at it if I was starting with dirty metal and especially if it was important to guarantee the finish.

Most of what I make isn't for show or intended to last. Others make lovely clocks that become heirlooms and models that win Gold Medals in competitions! Their secret is perfectionist attention to detail, and not the corner cutting for quick results I prefer.

Dave

I bought the Nickerson. Results was very patch but i suspect i did not clean and degrease properly

Stuart's photo illustrates well that most bluing methods (with the exception of the gentle heating to tempering colour method explained by Martin in his post above) result in a black or nearly black colour. I wonder why it got to be called bluing?

Rod

Now retired but back in the day many moons ago when teaching metalwork we had a tank of 'Whale Oil' that was used for blueing.

Rod, I think you will find that blacking and blueing are two different processes. Blueing in the home workshop is a temperature sensitive process and blacking is a chemical one. On choices of material for blacking stay away from alloys that contain any chromium, don’t ask me how I know!