5
$\begingroup$

Long ago, I asked a question regarding the construction of metal weapons without the use of iron at all. In the answers selection, many candidates have been suggested, and they are:

  1. Titanium Alumnide

  2. Nickel Superalloy

  3. Nickel Alumnide

  4. Stellite

  5. Tungsten Carbide

  6. Zirconium Carbide

  7. An alloy of Titanium and Tungsten

For this question, I'm exploring a different kind of purpose: Stonemasonry. Specifically, I am looking for a kind of tool that could turn a dome of natural granite into a huge dome comparable to the Volkshalle of Nazi architecture, or a ring of foothills into massive walls.

With that sort of aim in mind, would any of the candidates listed above make good tools that would do the work?

$\endgroup$
7
  • 4
    $\begingroup$ Also among the candidate metal weapons without iron: bronze, which is distinguished by the fact that it is the only candidate metal that people actually used to make weapons. $\endgroup$
    – Willk
    Sep 3 '21 at 22:41
  • $\begingroup$ Bronze is too soft. $\endgroup$ Sep 3 '21 at 22:43
  • $\begingroup$ They make metalworking cutting edges from tungsten carbide, so I'll hazard a guess it'll do Ok for stonecutting. It's rather heavy and expensive though.... $\endgroup$
    – sdfgeoff
    Sep 4 '21 at 0:27
  • 2
    $\begingroup$ @JohnWDailey Tin bronzes are soft, other bronze alloys not so much, "bronze" is a catchall term for any alloy that is mostly copper but where zinc isn't the second most abundant component metal, because then it is a brass. $\endgroup$
    – Ash
    Sep 4 '21 at 0:56
  • 2
    $\begingroup$ @JohnWDailey the Egyptians used bronze chisels, they may not last as long but they are definitely usable. most of your list is way way to hard to use in chisels, you don't want chisels to be too hard, or they shatter under repeated blows. a carbide rock chisel for instance only uses a tiny sliver of carbine on the cutting edge because a large piece would fragment under hammer blows. now a bronze chisel with carbide tip might work. $\endgroup$
    – John
    Sep 4 '21 at 4:21
5
$\begingroup$

Tungsten carbide cutting bits are a modern industry standard for drilling and hard rock mining because they abrade very slowing giving them a very long working life. They do need to be kept cool so water, oil, or other more complex lubricants are needed. Tungsten carbide tipped drills and blades will do the bulk work very easily and then you want pneumatic and/or hand chisels, in tungsten (the metal not it's carbide that is) or an aluminium bronze (comparable to steel for surface hardness and shock resistance) if your metallurgy extends to it's manufacture. Then once the bulk cutting and smoothing are done Diamond, Zirconium Carbide, Corundum and/or Garnet at various grain sizes are going to be needed as abrasives for the finer finishing/polishing work.

$\endgroup$
10
  • $\begingroup$ you can't make a whole chisel out of carbide, 99% of it needs to be made of a softer metal or it will shatter. carbide drill bits have only a small sliver of carbide in the tip. $\endgroup$
    – John
    Sep 4 '21 at 4:24
  • $\begingroup$ @John Technically you can't make any of it out of pure carbide, what is referred to as "tungsten carbide" is actually powdered carbide suspended in cobalt, you could use straight tungsten metal though which was what I was suggesting but hadn't made clear. $\endgroup$
    – Ash
    Sep 4 '21 at 4:55
  • $\begingroup$ you can't make most of the chisel out of any form of carbide it will shatter within a few blows. tungsten alloyed or not, is not much better tungsten is also rather brittle. brittle chisels are worthless. $\endgroup$
    – John
    Sep 5 '21 at 23:57
  • $\begingroup$ @John Straight metallic tungsten is not particularly brittle or it would be useless for just about every industrial application it is used in, you do have to be carefully when trying to manipulate it though, because almost any compound it forms is, so if you get sulfur or carbon or even oxygen contamination the produce can becomes extremely brittle. $\endgroup$
    – Ash
    Sep 6 '21 at 0:18
  • $\begingroup$ it is brittle under impact, high tensile strength and impacts resistance are not always correlated. Aluminum suffers from this as well. there are impact resistant tungsten alloys but they all involve iron. It surprised me too, I thought for sure tungsten would be a good candidate. $\endgroup$
    – John
    Sep 6 '21 at 0:31
5
$\begingroup$

Bronze!

Bronze is softer than steel. One must do more work with a bronze chisel and must sharpen it more often. On the other hand, the need for several iterations with the bronze chisel vs one with the steel means that it is less easy to make a mistake. Bronze aged civilizations including Minoans and Egyptians used bronze tools for stonecutting and sculpting.

https://exarc.net/issue-2014-2/ea/use-or-not-use-minoan-chisel-ancient-technology-new-light

minoan chisel

After two hours the relief plaque was finished (See Figure 10) and Georgopoulos concluded the difference between his normal iron chisels and the bronze chisels were that the iron ones are more effective on limestone. So the real advantage of the iron tools would be in saving time (he stated that the iron chisel took out one third more per blow than the bronze ones did). However, the bronze chisels were very stable and easily controllable. He even thought that no. 52 was better for carving details than his chisel with a synthetic diamond cutting edge mounted on a steel handle. The reason for this was that the synthetic diamond chisel cuts too deep with one blow of the hammer and therefore is less controllable. The bronze chisel, on the other hand, did not cut so deep into the stone, which meant that the same line/s had to be cut two or three times instead. This meant that any mistakes could without difficulty be corrected; therefore the bronze chisel was easier to control and the work conducted with more precision (See Figure 11). He also thought that carving the details was much easier than he had ever thought with a bronze chisel. He had, so far, underestimated bronze as a material for tools! There was no difference in the feeling when carving with bronze versus iron chisels on a soft material as limestone. It felt like using his ordinary iron tools.

$\endgroup$
7
  • 2
    $\begingroup$ @JohnWDailey The properties of bronze vary enormously with chemistry, aluminium bronze is comparable to steel in terms of hardness and toughness, tin bronzes with 1-2% cobalt take and hold a better edge than steel for knives and swords, silicon bronze is comparable to steel for spring tempering. In short bronze can be superior to steel in all ways but not at the same time, there are always trade offs; aluminium bronzes are brittle they tend chip, tin/cobalt bronzes are excessively ductile and those blades bend easily, silicon bronzes won't hold an edge and have are difficult to forge as well. $\endgroup$
    – Ash
    Sep 4 '21 at 0:36
  • 1
    $\begingroup$ @JohnWDailey a soft metal is better than a metal that is too hard, a soft chisel just wears out, a brittle one can seriously injure the user. iron chisels are softer than $\endgroup$
    – John
    Sep 4 '21 at 4:11
  • 2
    $\begingroup$ Those freaking layabout pyramid builders. $\endgroup$
    – Willk
    Sep 4 '21 at 17:02
  • 1
    $\begingroup$ @JohnWDailey no you asked for a metal that can do the job that is not steel or iron, which leaves only a very small list of metals that can withstand repeated hammering. Which is not true of anything on your list. $\endgroup$
    – John
    Sep 5 '21 at 15:05
  • 1
    $\begingroup$ @JohnWDailey if they had used harder chisels then they would have taken a lot of time anyway, maybe more...too many chisels breaking and sharp pieces of metal hitting the arms and eyes of expert workers. Human experts in their job take decades to replace, a chisel takes a few hours or days. That's literally the reason modern cars are soft and easy to break on purpose...if the car doesn't break then the guy inside certainly does. Humans are more important than tools. $\endgroup$ Sep 5 '21 at 15:34
4
$\begingroup$

The answer is simple... combine them all together

Some material scientists at Southern Illinois University mixed Nickel, Aluminium, some carbides and diamond grit in a zip-lok bag, threw it in a (super) furnace and out poped a material so tough that, well, I'll let them explain...

"Most drill bits used in mining coal consist of tungsten carbide and cobalt. They can wear out in as little as 20 minutes... [The new] composites easily cut through cast iron and granite with hardly a sign of wear. In fact, when testers cranked up the power in the granite test, the granite exploded, while the composites, though red hot, remained intact

Mounted face down under 50 pounds of pressure for 30 hours on a diamond polishing wheel running at 400 rpm, the composites wore out the diamond disk!"

Considering this was a powered test under industrial mining conditions, I'd wager that if you gave a chunk of this stuff to a regular stone mason, he'd be handing it down to his grandkids long before it ever wore out. Could make for an interesting story element...

"The fabled stone-grinders, forged long ago by the great mage Billiton, nigh-indestructable, have served the Grand Mason's guild for generations"

$\endgroup$
8
  • $\begingroup$ Fineness of measure will be an "issue" (as in you simply can't fine tune such a complex mixture successfully without precision digital scales), but yes a composite material does have potential advantages. $\endgroup$
    – Ash
    Sep 4 '21 at 2:24
  • $\begingroup$ abrasion resistance it not a great measures for chisels chisels need ot be flexible enough not to shatter under repeated blows, which is not a question of hardness. $\endgroup$
    – John
    Sep 4 '21 at 4:08
  • $\begingroup$ Looks like one of the Willks answers, but link is not a joke, however it is 2005 article, interesting what happened to all that after 15 years $\endgroup$
    – MolbOrg
    Sep 4 '21 at 7:59
  • $\begingroup$ A carbide composite might actually make a decent rock chisel (technically, all modern carbide bits are composites but anyway), all my rotary-hammer drill bits are carbide tipped and ground to a lightly rounded V-point, they hold that edge pretty well even though they're getting pounded hundreds of times a second. Only wood chisels need to be razor sharp, carbide for steel and carbide for rock are more like beveled bricks, couldn't cut yourself on them if you tried but they work well for their intended purpose $\endgroup$
    – Samwise
    Sep 4 '21 at 23:11
  • $\begingroup$ @Samwise carbide tip and made of carbide are very different things, both carbide and Nickle-aluminum alloy are brittle and will not withstand repeated blows. if the shaft or head of a chisel are made of either of these do not expect it to last an hour. $\endgroup$
    – John
    Sep 5 '21 at 15:02
2
$\begingroup$

Bronze or normal titanium, plus nearly anything on your list as a tip.

You can't use anything you list for the bulk of the chisel, many will work for the cutting tip, but the bulk of the chisel, especially the head and shaft, need to me made of a metal that is impact resistant. Everything you list is too hard and will shatter. Stone cutting chisels need a very narrow range of properties. Cheap chisels make the whole chisel out of softer steel because a dull chisel can be easily resharpened. In fact this is what is done for most of history, medieval castle makers would reforge (to sharpen) the tip of masonry chisels every other day. More expensive stone chisels use a small tip of hard metal (for wear resistance) embedded in a shaft of softer more impact resistant steel, like the one below, but you have to surround the tip with a different metal to minimize the stress on the tip.

As a paleontologist I have worn out hundreds of hand chisels and have made dozens (this is actually why I learned blacksmithing). Chisels for use on stone are tricky things the tip and shaft of the chisel need very different properties.

Hard metals will shatter under impact, A chisel whos shaft is made of a hard brittle metal will last no time at all. A shattered chisel is scrap metal and worse has a decent chance of injuring the user. There is a reason we don't harden stone chisels too much, stone chisels work by transferring energy for impact, the chisel needs to be impacts resistant, usable chisels can flex. Hard metals work great for masonry chisel tips but if the shaft is made of them they shatter, this is even a risk with with steel chisels if overhardened. Don't believe me, take a carbide tool and start smacking the carbide portion with a hammer, see how long it lasts.

There are not many metals that are both stiff enough and impacts resistant enough to make the bulk of a chisel out of, excluding steel you have bronzes (including aluminum bronze), titanium, or titanium iodide. Bronze is by far the most available but failing that titanium will work, they will just be costly to manufacture.

enter image description here

$\endgroup$
2
  • 1
    $\begingroup$ @JohnWDailey bronze chisels rarely chipped they mostly dulled, when they did chip it was due to the low quality of the metallurgy, also I did provide alternatives, there just are not many things that will work. $\endgroup$
    – John
    Sep 5 '21 at 15:23
  • 1
    $\begingroup$ "Bronze has already been used. I'd rather try something unique." - gods of chaos, give me the power /end rant. $\endgroup$
    – MolbOrg
    Sep 5 '21 at 20:23

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .