[Justin B.]

So I was thinking about the Mammen axe today, CAS Iberia's repro of it, and whether or not you can get that effect using period metalworking techniques.

In other words, is it possible to take a metal thing (like hilt furniture) and hot-blue or blacken it, then add an inlay of some other metal, like silver? Or vice versa, for that matter... I haven't the slightest idea what happens if you expose silver or gold to the hot bluing process.

Anyway... anyone able to satisfy my curiosity here?

[Hadrian Coffin]

I would look around for the topic on blued viking sword hilts. It is impossible to say with certainty as we do not know the original finish on the originals when they were new. The only way I can think to blue something historically is with heat and oil. The problem is that it will rub off very quickly and thus is somewhat pointless. The original Mammen axe is iron with silver inlay. Iron is fairly dark on its own (darker than steel) silver is fairly bright (brighter than steel), as such the inlay would pop on its own without the need for any sort of blueing. Cas Iberia probably uses cast steel parts, blues them, and then scratches the pattern in. It is an easy process (much much much easier than inlaying it) and looks nice in photographs.
Cheers,
Hadrian

[Justin B.]

Yeah, I'm really not interested in copying the CAS axe, but the effect is nice enough. Since I can't afford to commission something the size of a sword from someone who works in iron, as opposed to steel, at this time, this seemed like a reasonable enough compromise. But everything I've read on the subject of inlay suggests that it needs to in before the final polishing, and I don't know what happens if you bathe a transition metal in a bluing solution.

Is there already a thread to this effect? If so, I can't find it.

[Ben Potter]

Normally when you etch steel that has been inlayed with non-ferrous metal you need to seal the inlayed part with wax, pitch, lacquer, nail polish etc. As for heat blueing I have done that with copper before not silver but I don't see why it wouldn't work.
Alsl there is no reason that they didn't use chemical bluing, there are many natural compounds that will blue/etch and darken steel (onion, lemon,apple juices are very commonly used to darken and protect carbon steel kitchen knives)

Hope that helps.

[Hadrian Coffin]

Certainly it's possible they used chemical blue. My problem with the idea is that we don't have any evidence I can think of to suggest blueing. It seems like a waste, blued metal doesn't stay blue/black it wears off. I can't think of any hard evidence of blueing in the Viking era, later periods for sure but not Viking. It is possible, everything is possible, the question is if it's probable? I have seen many artifacts but I haven't seen everything, not to mention the objects still waiting to be found.
You can use chemical blues after inlay with most inlay materials. I have done silver inlay on steel and then blued with Super Blue with no ill effects.
Cheers,
Hadrian

[Ken Speed]

i don't have any direct experience with the Mammen axe but I seem to remember reading somewhere that the "etching" is actually painted into incised lines.

[Justin B.]

[Jeff Pringle]

Fine silver is not affected much by chemical oxidizers that darken steel/iron, so if you inlay pure silver instead of sterling you should be good.

[Alex Indman]

I hope resurrecting a very old thread is not frowned upon at this forum. But I was going to ask almost exactly same question, did a quick search first and found this.

In my case, I am attempting to make a mild steel (1018) guard and pommel with a little simple silver inlay (fine silver), and want to finish steel to black/blue for a nice contrast with silver.
I expected that using a cold bluing compound (PermaBlue brand) will be perfect, leaving fine silver unaffected just as discussed below. But when I tried on a little scrap piece, in fact it did affect silver - it turned kind of dirty grey. Any attempt to clean takes off the blued finish from steel as well. Is there any trick to it? Maybe I should try some other bluing solution?

BTW, as a potential alternative I experimented with simply heating the piece on a gas stove.flame. It actually turned pretty decent black/blueish color, and silver stayed bright, nice contrast. But I guess it would be harder to achieve even color on the big, long guard (can't be heated all at once). And the biggest problem with this method - I have a silver soldered part in the guard (a decorative nickel silver plate inside the side loop). If I go with heat bluing, the plate will have to go. I like the looks of it and it took me quite a bit of work to make, so I don't want to get rid of it unless there is no other way. Not to mention that heat blued parts can't be touched up when finish wears up with use in some spots.

Any suggestions will be greatly appreciated!

Thanks,
Alex.

[Tim Harris]

I've had perfectly acceptable results using a domestic oven, Alex - electric in my case. I just let the parts sit at maximum heat until they reach the right colour.

[Alex Indman]

Tim,

thanks for the tip, it sounds promising. I will run some tests to see if my oven can produce temperature that blackens steel but doesn't yet melt a soldered joint. I have a few more questions, if you don't mind.

Do you know what temperature your oven was supposed to produce at max setting?
How long approximately did you have to keep the parts in there, waiting for color to change?
How durable do you feel the resultant finish is?

Thanks,
Alex.

[Jeffrey Faulk]

[Tim Harris]

Jeffrey has already covered some of your question Alex, but for what it's worth, my kitchen oven goes to about 250C (I'm not at home at the moment, so that's just a recollection).
Time will depend on the size and thickness of the piece being blued. I have never run a clock on it... I simply check periodically to see if the right colour has been reached.
Like any other surface treatment, the finish can be removed by abrasion, but in my experience, it will survive general usage. A coat of silicone wax helps preserve the blue, although it dulls the colour slightly.

[Alex Indman]

My oven also has 550F max setting, so it must be the US standard.

Anyway, the results of my tests were both good and bad.

The good part is that at 550 degrees, in about half an hour, I get pretty much ideal deep and even color on steel, while silver stays bright. See attached picture (the test piece is about 3/8" wide), it doesn't of course capture the real quality of color but does show nice contrast between steel and inlay.
The colors are way better than anything I could achieve with PermaBlue treatment and cleanup.

The bad part that the solder I used melts in the process. It melted even in a 450 degrees test (which produced only an inadequate straw color on steel).

So when I am done with inlay on the actual guard, I will go ahead and give it the 550 degrees treatment. If I am lucky, the soldered piece may stay in place by friction and retain enough solder in the joint to re-attach when it cools. If not, I will clean up the inside of the loop and mentally chalk it up as a learning experience. Should have done all this testing BEFORE spending most of a day to make, fit, and solder that plate in place...

Alex.

[Alex Indman]

Hi,

resurrecting this topic to post the results of applying the discussed technique to my latest project. I made a complete set of fittings (guard, pommel, handle collars) out of 1018 mild steel with fine silver inlays.
As I expected, anything attached with regular solder wasn't compatible with heat bluing at 550F in my oven. But the high temperature silver solder that I used for the collars (working with it was more like brazing than soldering) held up just fine.
Took more time for more massive parts to achieve same color: almost 1.5 hrs for the guard and 2 hrs for the pommel.
Color is quite consistent all over, deep black-blue with some purplish highlights, depending on light. See the attached picture, unfortunately not greatest quality.
Happy with the result, thanks everybody for the suggestions given here!

Alex.

[Greg Ballantyne]

That turned out very nicely Alex. I'm surprized at the deep even color, and the inlay really stands out.

[Alex Indman]