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Metal Working and Metallurgy

DreadKhanDreadKhan Member Posts: 3,857
There have been many discussions about weapons, armour, etc, and a topic that often comes up is metal working, so I thought I'd make a thread to discuss a topic dear to my heart, metallurgy. I'm not a chemist, but metal has been a hobby of mine for years, snd I do have some formal metallurgy education, so I might be able to answer any questions.

Also made the thread because I felt like blabbing a bit about an experiment I'm slowly working on. Using some very brittle (and likely extremely cheap gray cast) cast iron scrap from a burner, I welded a thin strip (~1/8th, maybe 3/16th thick, and a bit under an inch wide, 4 inches long) I cut and partially cleaned (did not grind out pits of rust) to some structural steel (low carbon, the cheap stuff). The goal was to make a fairly hard edge for an axe I'm working on, while still having the bulk of the material still soft and thus not brittle. Well, I did a solid job getting the cadt iron welded on, then added more welds to dilute the VERY soft, brittle cast iron. I have just finished grinding it back down to look axe-like, and curious what the proprrties of the diluted metal are like, I put a very sharp edge on part of it. Then, being the wannabe metallurgist I am and having no tools to test, I checked if the newly made steel was harder than structural. The new edge without a bevel could shave structural steel, without noticeably dulling. :D Sounds like I made carbide!

So, pretty hard, especially since this isn't even hardened! Next I'll be using it as an axe, after I carve out a sturdy handle, to test resilience. Just welding that bit of cast is an accomplishment, really. Its prone to cracking pretty badly. And just straight up burning... as in, it burns if you weld it too hot.
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Comments

  • The_Potty_1The_Potty_1 Member Posts: 436
    Oh wow. So is there a layperson's guide to finding out if a metal is brittle or not? Probably the most reliable method is to get two, and destruction test one of them ...
    lolienDreadKhan
  • DreadKhanDreadKhan Member Posts: 3,857
    Well, brittleness can only be tested destructively. Usually you would test impact toughness, and by examining how the tested material broke during the test. If the metal deforms rather than cleanly snapping, the material is not brittle. A general rule you can count on is that anything cast will be more brittle than the same material that wasn't cast. If brittleness is an issue, the metal is reheated and annealed (very slowly cooled), as it removes all stresses, which includes any form heat treatment (hardening, tempering) as well as mechanical stress. This makes the metal as soft/non-brittle as possible. Obviously softer can create new problems, and some materials will still be very brittle, but annealing is useful.

    Other than cast, the rule of thumb is that higher tensile strength/harder materials are more brittle. So, carbide tends to be brittle, while bronze is not. Finally, if you cut a sample off, you can polish snd etch it to microscopicly examine the grain structure of your metal, and gain some insight into composition. You don't need a grest microscope for this even!

    The final easy option, and best, look up the information for the classification of your metal. Codes exist to dictate minimums and maximums for metals, both in terms of mechanical properties and chemical composition. Brittle materials will perform poorly under the impact testing, but verify the test wasn't done in very cold conditions. Materials are often tested sprcifically to verify thst even in extreme cold they remain ductile. So if you aren't using equipment in -40 degree weather, your material doesn't need to handle it!
    lolienJuliusBorisovSethDavis
  • DreadKhanDreadKhan Member Posts: 3,857
    Well, I put the axe head on a handle (not a great one, but I can't use a standard one for it, as the eye is very wedge shaped/big. I am going to make a better one this weak from some elm! Should be superb for the job), and I tested it on some existing cordwood. The handle was a bit short, but still functioned fine. Not only did the ultra hard edge not get damaged, it actually got sharper. :o

    I did a much less gentle test out of extreme curiosity, and having read some likely a bit exagerated stuff about true damascus swords remarkable properties... I tried chopping a nail. First fairly gentle, noted a significant mark on the nail and no effect on the axe! So, I wacked it harder, making a bigger mark, still no damage to my new axe! So I gave it a decent blow, hard enough to sink the nail into the 2x4 sideways, and put a very significant mark on the nail. No mark on the axe! :D

    Tommorrow I'll try putting a nail on some hardwood, so it'll actually get cut I hope, rather than sinking in so much. Very good start on my experiment! Might do some fine tuning on the axe head to improve it's splitting performance.
    lolienJuliusBorisovSethDavis
  • meaglothmeagloth Member Posts: 3,806
    Excellent thread. As I posted in my Halloween thread, I made a steel sword for my little brother last week(he was a knight)
    image
    It's very minimal. That's the nice word for it, anyway. No edge, no point, only a costume piece, I just wanted it to look cool(I sorta got there:/) I bought the metal at a normal hardware store, where for some reason they sell long, strikingly sword-like pieces of steel. I honestly don't know what it's called or intended to be used for.
    I used lump charcoal in a chimney and put the leaf blower in it, which gets surprisingly hot. I was able to pound out a tang and a little but of a point with a small hammer on a granite landscaping boulder:)

    I told you it was minimal.

    After that I did a significant amount of sanding with a little drill-driven power grinder.

    The tang is sideways, to short and to thick, so I wasn't able to attach the handle properly. The pommel is a pice of compeer pipe filled with sodded wire and duct taped on to the end, and it doesn't quite weigh enough. The guard is a piece of wire I cut out of a yard sign.
    I was able to drill one hole for a screw so I could secure the handle, but I was mysteriously not able to drill another one anywhere in the tang with any assortment of drill bits.

    Over all it was an... Educational experience, but I think I was good enough for and 8-year olds costume. I wouldn't try and poke anyone with it though.
    lolienAristilliusJuliusBorisovBlackraven
  • CrevsDaakCrevsDaak Member Posts: 7,155
    meagloth said:

    Over all it was an... Educational experience

    I once tried to melt a tiny little piece of gold (yes, gold, I probably got it from a broken piece of jewellery form my mother), and I was rather successful… But what I did wrong was putting my finger's tip over the melted gold… which was a serious educational experience (and rather ironic considering two months ago that, I had picked up a bit of burnt coal form the ground, and to my surprise it had a temperature of more than one hundred Celsius degrees) :p
    meaglothlolienBlackraven
  • The_Potty_1The_Potty_1 Member Posts: 436
    I was inspired by this to make a staff, and although I can already see some problems, it seems to have potential. First off, while wood is typically the material of choice, I really don't have the tools to work a large piece of oak or other hard wood.

    I have a walking stick I made in varsity, which is around 1.6m (5 feet), as opposed to most sticks which are about 1m (3 feet). It's an inch or so wide (30mm), so nice to grip. I basically grabbed a wooden curtain pole from my dad's workshop, carved a snake head on one end, and fitted a copper ring on the other end to prevent splintering. Unfortunately it's really light wood, so good for walking and carving, but bad as a weapon.

    This was the snake head, although narrower, chosen because I'd just been to Vic falls and did the white water stretch there.

    https://en.wikipedia.org/wiki/Nyami_Nyami

    Anyway, on to the current stick. I bought 2m (7 feet) of copper pipe, 22mm I think, which is a bit too narrow. I may wrap some leather around it at two points. Inside this are two 1m segments of 10mm threaded rod, with a coupling nut on each end and a third one joining the two rods. Two copper end pieces finish it all off. The entire thing will probably be pretty robust when it's done, but is currently a bit light. Also inconveniently long, but the rods are probably beyond my ability to shorten. The rods are currently rattling around in the pipe, so need to be fixed in place.

    The first problem is I have no idea how to weld copper, but it's probably not that hard if you don't mind making a couple of mistakes. The weight I plan to address by filling both ends with lead fishing sinkers, and then heating to melt the lead. This should stop the ends rattling, and I'll probably wrap the centre coupling nut in a piece of rag or something.

    Obviously this can go wrong in lots of ways, firstly, if the copper end pieces come off, then molten lead will pour onto my heat source, and toxic fumes will put me in the hospital. So I'll probably do this outside over a benzene hiking stove, with insulated gloves, a mask, and remembering to hold the end piece on.

    Secondly, the top sinkers could slide down while I'm melting the bottom end, which would give me a staff with one heavy end and one light end. Well actually it couldn't because of the central coupling nut. So actually I can leave the middle section empty. I initially thought of putting river sand in the middle, but that would mix in with the lead too much.

    So, do you think I need to solder the ends closed before I melt the lead, or can I do both in one go? For that matter, they used to use lead as solder, only stopped because toxic water sux, so do I even need to solder at all? Probably yes.

    Another point, once I have one end done, and I'm heating the other end, is copper a good enough heat conductor that the first end will melt again?

    On that note, there's a chance that the little hiking stove won't even get the end I'm heating up to 330 degrees C (621 degrees F), so the lead won't melt at all. Well hey, then I'll get a proper gas torch. My mother-in law will be happy with that, she keeps talking about making creme brulee.
    lolienDreadKhanJuliusBorisov
  • meaglothmeagloth Member Posts: 3,806
    This isn't strictly speaking metallurgy, more like... Well arts and crafts if I'm honest , but I made a gauntlet of sorts with a ratty old garden glove and some left over aluminum flashing. It's not particularly pretty, though I was hoping for some functionality(it's really doesn't take much to protect from blunted practice swords) and I think it holds together pretty well, though I have yet to do anything other than move it about one my hand.
    Based on the thumbnails these my not be right side up so I apologize in advance. Also, the looked more in focus on my phone screen:)imageimageimage
    JuliusBorisovlolienSethDavisNukeface
  • DreadKhanDreadKhan Member Posts: 3,857
    Looks pretty good! I note you got the overlap right for fencing... armour gauntlets overlap the other way, so your hand can move more, but this leaves openings to stab into when fencing. How do you choose to attatch the metal? Rivets?

    If you to make a heavier one, a welding gauntlet is perfect, even has the big cuff to protect your wrist, which is nice if you fence with jerks that whack your wrist. ;)

    Traditional western armourers were incredibly skilled, usually the best metal workers you could find. Working cold iron at serious precision sounds more like a machinist than a smith. In the east, some armour was even made of watered steel.

    I finished up my splitting axe and its handle, and have split some kindling. Seemed pretty effective, but the real challenge will be bigger piecesmof knotty hardwood. Might need to finetune the splitting aspect, but the weight is nice, and the eye seems to grip better than a standard axe or maul. I used a piece of live cut elm for the handle... unfortunately, its not very carvable wood (so I had to mostly sand... ugh), but elm is really tough. Should be pretty strong, despite being light.

    My heavy kukri nearly has the edge polished up, so I can maybe put on a grip soon. I have cut some light wood, works similar to a hatchet, but is pretty sharp atm, and seems to hold the edge well. The edge is a welded on file, so its very hard steel, but the backing of softer steel indeed keeps it tough. Ancient technology can work very well! Looks scary as heck though, and the forward curve makes it cut interestingly... on a calm day, you can slice through a leaf and not disturb it (ie totally clean cut, no resistance). I have lighter, thinner machetes that can't do this... the blade is pretty thick actually, about 5/16ths thick, probably 3/8ths at the thickest beside the blood gutter. Probably do steel wire for the grip, then wrap with leather... might put a pic or two up this weekend.
    JuliusBorisovlolienmeaglothSethDavis
  • DreadKhanDreadKhan Member Posts: 3,857
    Doing a bit of forging in a wood furnace. Works decently, but its hard to get to the orangey yellowish very plastic state,so trying to draw out bars by hammer isn't practical. But, its still hot enough for cherry red, so I should be able to harden from that heat. Won't be at all consistent though, unless the piecemis pretty small.

    My bar of iron carbide I made is unforgeable... even after serious annealing. It cracks, which is kinda expected. I have some ideas that might help make this into a useful product, diluting imho will be important, and having a softer steel coating the very high carbon might well be the trick. So, sounds like some more welding! The neat thing, if I can keep the coating of ductile steel thin enough, grinding it off will still leave very hard steel, with a softer core. The other idea I have is forging the metal at pretty high heat, which might require a better heat source. If the steel is really hot, the structure changes, which might make the bar significantly softer during forging, allowing drawing out. The other plus, forging at this heat would remove some imperfections like gas pockets, which seem to be making my project brittle.

    Possibly of interest, I am working on forging some old mower blades. Until I get my goal steel, it might be necessary to play with this sort of thing to improve my forging technique. Hammering isn't as easy as it looks! Well, I'm burly enough the hammering isnt physically THAT arduous, but keeping the blows precise and flat is a bit involved. The one blade seems to be a carbon steel, as it was very rusted/pitted and is pretty hard, but the other is possibly an unusual stainless. Duplex I think, very very strong, but generally not super hard. Great for a machete though, and I might try and work harden the edge a bit, which would make it harder. It should be ductile enough to not risk cracking. Maybe. Heat treating will be... interesting.
    meaglothlolienSethDavis
  • meaglothmeagloth Member Posts: 3,806
    DreadKhan said:

    Looks pretty good! I note you got the overlap right for fencing... armour gauntlets overlap the other way, so your hand can move more, but this leaves openings to stab into when fencing. How do you choose to attatch the metal? Rivets?

    If you to make a heavier one, a welding gauntlet is perfect, even has the big cuff to protect your wrist, which is nice if you fence with jerks that whack your wrist. ;)

    Traditional western armourers were incredibly skilled, usually the best metal workers you could find. Working cold iron at serious precision sounds more like a machinist than a smith. In the east, some armour was even made of watered steel.

    .

    Wow, thanks for the advice! At the moment they are attached with duct tape. This was just a little craft I was doing cause I was bored one evening, but I was surprised how well it turned out. Most of my stuff disintegrates as soon as I try to put it on. I'll probably get back to it soon though.
    My mind is also shifting back to making my sword(a better one than last time) though I still need an anvil; landscaping boulders only go so far:P Thanksgiving break is coming and I'd like to get started on the sword I had designed for myself. I think I learned a lot and got some good practice from my first project and would like to attempt something a bit... Less duct-tapey. I have some new ideas(I've also abandoned the gas-fueled moonblade functionality idea for now, in favor of a more functional sword:) I'll come back to it though)
    DreadKhanlolienNukeface
  • DreadKhanDreadKhan Member Posts: 3,857
    No problem @meagloth‌ if you want more suggestions, post away. On swords, the easiest way to make a functional sword without much equipment would be to get a good piece of high strength steel, like tool or spring steel and using an angle grinder and vice (or big 'C' clamp) to grind edges on it. If you get pre-heat treated steel, don't let it get too hot to touch when you grind... it would take some hours, but it would work fairly well. Spring steel is used for functional reinactmenty western swords, its very tough obviously, and won't break easily. The hardest part hands down would be to attatch a pommel, since you likely don't have a welder. An option would be to use very strong metal glue to attatch a reasonably tight fitted piece of metal that the tang just barely fits into. It won't be ideal, but it'd be an accessible option.

    Asduming you can get some useable steel, try for ~3/16 thick. Any thicker will be absurdly heavy for a normal person, and not much stronger.

    An option might be to visit a scrap dealer actually, if you don't have a local retailer of 'exotic' metal. I have made very functional tools from scrap, including a massive tree chopping sword, which was made in a not dissimilar way to what I explained... its not really a sword, but its cut down many hardwoods with very little maintenence.

    I would make a couple knives first, getting bigger each time before tackling a full size sword. The techniques will be comparable, but mistakes will be cheaper. You can also make a practice sword out of the steel sold at smaller hardware stores. Make sure its hot rolled steel, not shiney cold rolled, which costs more and is brittle! By grinding out a cheap practice sword (which you would use for actual practice!), you can finetune what weight and balance is comfortable for you! Custom stuff is nice for this, because few sellers know how to 'pick' a sword that'll fit your build correctly, if they even carry such a sword.

    If you use unheat treated tool steel, don't worry too much, it won't be as hard, but will be quite durable. More sharpening, but the blade won't snap! Properly hardening a sword eould require a fair bit of heat, and tempering it well is an advanced technique.

    If you buy an anvil, make sure it isnt too small... bigger is definately better. Ideally, it should ring nicely, if you tap it with a hammer, but some good ones don't ring, so thats not a strict rule. Used to be there was only one was to make an anvil, to cast it whole. Not true anymore!
    meaglothlolienSethDavis
  • meaglothmeagloth Member Posts: 3,806
    edited November 2014
    Thanks. I was already aware of spring steel being a good choice, and I have been meaning to visit a junk yard for various projects for over a year:)
    I don't really have any tools to speak of but for a hammer, a small drill-powered sander, and a drill with some various bits scattered about the basement floor. I think, like usual, I will mess around until I either find something that looks good or get tired of not finding something that looks good.
    As for anvils big seems to be hard to find. I don't have $600 to drop on normal stuff, let alone a real anvil. I was thinking along the lines of these "railroad track anvils" I keep seeing on ebay:
    http://www.ebay.com/itm/VINTAGE-RAILROAD-TRACK-ANVIL-15-LBS-BLACKSMITH-SILVERSMITH-ETC-/131351699238?pt=LH_DefaultDomain_0&hash=item1e952bdf26
    Or find a cheap, no-$20-shipping equivalent on that eventual trip to the scrap yard.
    DreadKhanlolien
  • DreadKhanDreadKhan Member Posts: 3,857
    Yeah, a non-traditional anvil is usually plenty for lighter stuff, its not like you're forge welding ship anchors! Heck, if you're really, really cheap, a hefty steel plate 1/2 inch thick securely attatched to a solid frame would work. Wood, including soft wood, is a good option for a base. The three main concerns with an anvil are will it move a lot when you hit it (must be heavy, or secured firmly), can it take a beating (thicker metal is a plus, but metal must be fairly malleable and shock absorbant), and provide enough surface to work on properly. Mine is a bit small, but it works for now. A scrap yard should have something you can use, but you might need to use an angle grinder to make it smooth enough.

    An angle grinder is a pretty cheap tool, and VERY fast compared to anything similar. Try to get a 5in one if you do, they tend to be more rugged than 4.5in ones, and you can still use either size disc. You need eye protection, and a cheap air particle filter is sensible (but most guys wouldn't bother unless they are doing serious grinding). There really is no substitute though for the kind of work you're thinking about though. I can't think of a more useful tool than an angle grinder for metal work, honestly. You can produce very high quality blades without an anvil or forge, and with relative ease if you have a grinder and a good vice or clamp.
    meaglothSethDavis
  • The_Potty_1The_Potty_1 Member Posts: 436
    I'm still around, just trying to source a couple of kilos of lead. I think there's a scrap merchant out by my wife's stables, but it just occurred to me that my brother-in-law's old diving gear is gathering dust in my garage at home. I'll go and have a look tonight, perhaps a couple of weights are ready to be repurposed :D
    lolienDreadKhan
  • DreadKhanDreadKhan Member Posts: 3,857
    Well, in a feat of manliness aproaching epic level territory, I made a small but heavy straight razor, for shaving. And have started shaving with it. I can do okay on the flatter areas, but the chin and mustache need more advanced techniques I think. But it worked! I have a 'replaceable blade' type straight razor, but I do not like using it terribly much, but this thing seems better. I look forward to seeing how much stropping it needs after a full shave, but I expect it will hold up better plain high carbon steel.

    Bringing it back to metallurgy, I made the razor by taking some scrap structural steel, and then welded on a piece of gray cast iron, and the diluted it down to what is probably a very high carbon steel, or a very, very lean white cast iron, as I also hardened the blade after I had it 'done'. I had to re-grind the one side a great deal though, after I found my bevel (IE the angle made by the blade in this case... needed to be much more acute, to make the edge thinner) to bulky. So, I hollow ground one side and was pleasantly surprised to find what appeared to be some graphite bearing cast fairly far into the hollow grinding, so I have a nifty looking razor now, should I choose to do more finishing work on it. I hope to examine this under a microscope some time, to see what the grain structure is like, especially the transitions from low carbon to welded cast/very high carbon, and even look at the piece of cast. Depending on the light, the welded portion is a slightly different shade than the structural steel, which is also cool, and this will likely become more pronounced as the blade gets a bit of oxidation going, as they should not be affected exactly the same. I could etch it too, which would bring out the difference sharply, but I suspect shaving foam will help etch it anyways over time.

    If anyone is curious, you really cannot put a mirror finish on cast iron if it still has ANY graphite present... white you probably can, but it is not going to be fun polishing that. That cast iron I welded on must have a ridiculously high carbon content though. Diluting it is nifty.
    lolien
  • meaglothmeagloth Member Posts: 3,806
    edited April 2015
    I got an old "toy" $10 katana blade from a friend(it's had fallen out of the handle and they where using at a fire poker) and I've started making it into a saber. It's obviously not spring steel, it bends rather than spring back, and I don't know how strong it will be, but I got to use my angle grinder for the first time today and it's coming along nicely. Here's what it looks like now:
    imageimage

    I shaped it by forging it with a charcoal fire in our grill, using a railroad tie-ish board we have from when we redid a retaining wall as an anvil.

    Boards are shitty anvils.

    But I got it done anyway and today I ground it down some. Also I cut out a guard a little while ago.
    image

    Its 22 gauge steel so it's a little flimsy(apparently I want like 18) but I can make it work. I cut it out with tin snips and bent it with my hands an a little bit of hammering.
    Post edited by meagloth on
    NonnahswriterlolienJuliusBorisovCrevsDaak
  • DreadKhanDreadKhan Member Posts: 3,857
    If some has heated it, IE using it as a fire poker, that would probably remove the temper from the steel, though you shouldn't have lost it unless the steel started getting coloured oxidation. Dark blue and purple are very soft for tempering, so if it hit that colour-range, it would be no longer springy. Even less dark colours would affect the springiness and hardness, but practicing on something you won't mind making a mistake on is a good thing. You might have heated it during grinding too actually, but you probably will be able to use it for your purposes anyways, as it doesn't require edge retention, it's not like you're cutting shrubs up with it I would think. One trick to make the edge a bit harder that might work for you is heating it to the lower end of plasticity... ie when it is not terribly soft, but still softer than when cold, and forging the portions you want harder. This will tighten the gain structure up a bit, and add stress to the metal there, which will make it harder and stronger. You could even cold forge it a bit, but you can break it that way, and it can be hard to make much of an impact. Steel responds to stress by getting stronger up to a point, and this is a viable alternative to heat hardening for some uses. Machinists often use cold rolled steel for this reason. I have seen some tree/scrub chopping hand-tools that are work hardened, rather than being heat treated, but it would depend a bit on the chemistry of the steel. Higher manganese means better work hardening iirc, though actual manganese steel is pretty strange stuff, and not likely to be showing up outside of scrap from pretty big/heavy equipment. Plow parts and railroad stuff iirc.

    22 gauge is pretty thin, so you might actually be able to heat that pretty hot on a smaller fire. Worth considering, for harder to do bends. Then again, heating it will cause it to shrink, so maybe just use pliars and a hammer like you're doing is good enough.

    How do you intend to attach the guard? What is your plan for the grip? As I have mentioned, I like wire wraps, which can be supplemented with other wraps afterwords if needed. You would want either copper, aluminum or galvanized steel wire for that, and relatively thick is better, though you will need pliars to get a tight wrap.

    Good work!
    lolien
  • meaglothmeagloth Member Posts: 3,806
    I seriously doubt it was ever decent steel. Katanas aren't spring steel anyway, and this was very likely less than $30.
    I was going to try to temper and quench it(with an admittedly absurd element of lottery, given my experience) but it's been rainy and I'm vey impatient.
    I have actually worked with it cold quite a lot. When I got it it was extremely bent and I hammered it straight while it was still cold.
    Evenly heating by itself will be hard enough without the added challenge of trying not to burn down a nice suburban neighborhood while tossing a red hot sword into a bucket of oil.
    lolien
  • meaglothmeagloth Member Posts: 3,806
    I'm going to drill a hole and shove the tang through, then attach a wooden handle that extends farther than the tang(which is very short) and screw the other end of the guard into the wood. I don't know how well I can actually produce a wooden handle though. I may end up putting rivets or copious amounts of superglue through it to keep it stable.
    lolienCrevsDaak
  • DreadKhanDreadKhan Member Posts: 3,857
    Carbon is a very cheap element though, but I agree, it is not going to be anything too interesting.

    I have quenched in mixed oil, mostly used motor oil, which seemed to not be a terrible fit. Might add carbon to the outside, but not very much I would wager, unless you are quenching it many, many times in that stuff.

    Hardening temperature for most steel is decidedly red, you might want to find a good way to block sunlight, or do your hardening at night. Cherry red when its pitch black out is much cooler for hardening purposes than cherry red in bright light! Its hard to get things hot enough evenly without a pretty big, controlled heat source, but kudos for giving it a shot, I hope it works out well! Hardening is much easier than tempering, once you have a suitable heat source... I have heard of people using ovens and the like, to get the right temperature, but the coolest way I have heard for swords was to really heat up another bar of iron, then use THAT as the heat source, since the steel only needs to get up to probably 300 farenheit, you can use this trick to get differential hardening, which is one of the secrets to a really, really good sword. If the whole blade is as hard as you want the edge to be, it'll be brittle, but if you can keep the bulk of the sword tough and a bit springy while making the cutting edge only lightly tempered, it will be better. Final point, people sometimes do repeated temperings to refine the grains of steel. The key is to not overheat obviously, as getting past the dark yellow stage for the edge of the blade is likely to be too soft for a sword (probably just fine for an axe though).

    Wood can be nice, I have put a wood grip on a machete I bought ages ago. It came with a guarded single hand only grip, which worked, but wasn't as versatile as I wanted, so I put a nice, long two-handed grip on it. It's a biggish machete, and using it with both hands can get some power behind it. Wish the blade held a better edge maybe, but it's stainless, so you get the joy of 'hard to sharpen' mixed with 'does not hold an edge well'. Go figure!

    The way I put the handle on was to cut a slot (the handle is much longer than tang in this case) in a piece of good hardwood, the drill holes matching the machete's holes, and I used brads to attatch it. A brad is what people most often use to attatch shovels to their handles... never came close to failing, and used no glue. It was seasoned hardwood though. If you have a broken shovel or other handle handy, that wood is probably pretty good for what you need. If not, I would suggest finding a dry piece of hardwood, and carving something. I would also wrap it with leather after putting a wood handle on, or for a utility tool, I use athletic tape, which offers very good grip, and looks pretty badass.
    meaglothlolien
  • meaglothmeagloth Member Posts: 3,806
    So I got impatient and put a handle together. I split I maybe 1.25" diameter stick from by backyard and riveted it to the tang with drilled holes and nails the same way I did with my other sword, and then nailed the bottom of the guard to one of the split pieces(which made it slightly off center, but you don't really notice. I then wrapped it all in electrical tape, and the balance point was ~6.5" off the top of the hilt, which felt unwieldy, so after some experimenting, (soldering is harder than it looks) I settled with twisting a bit of coathanger around the bottom of the hilt and taping over it so it wasn't abrasive. Not the balance point is about 5 inches of the hilt which is bout right for a saber(slashing cavalry weapon)
    The grip is a little thick than I would have liked but I have small hands and any smaller wouldn't really fit on the tang, or be reliably sturdy. Overall I think it's ok, but I'm sure I'll ruin it completely while tinkering later. image
    DreadKhanlolienJuliusBorisovCrevsDaak
  • DreadKhanDreadKhan Member Posts: 3,857
    ...made and fitted up a slotted ashwood handle for a huge machete, looked okay, got everything drilled and roughed out, put in some very large brads (probably a dumb choice in hindsight) and then watched in bemeusement as the handle split in two. Not along the slot, where you would assume it might, as it's a big slot (...), no it split along the brads. I this wasn't dead wood that I was using, but it WAS highly stressed young growth, as opposed to less stressed wood from older growth. So yeah, much as I hate working with it, looks like elm may be required for this handle too. Which sucks, since elm can't really be worked with hand tools, and I mostly am at the hand tool stage. Probably added the lethal stresses when I pounded the brads in. Stupid ash and its easy splitting ways!
    lolien
  • meaglothmeagloth Member Posts: 3,806
    I've been doing a lot of different things lately(mostly making chainmail) but I think this is most directly related to metallurgy and the most exciting.



    That said I would strongly recommend trying to find a better crucible, I bet if I kept that in much longer it would have failed. But there it is. Once I have a few ingots I plan to cast a crossguard for a friend's wooden claymore, then maybe a hilt for a rapier, but I'd rather have that out of steel. I have very little experience with aluminum so I don't know how it would handle that kind of stress.
    JuliusBorisovDreadKhanlolien
  • DreadKhanDreadKhan Member Posts: 3,857
    Aluminum is a really, really weird metal if you have only a background with steel/iron. It has alloys that can't be welded (as in, LOTS of them), and even done perfectly, a weld on an aluminum part will always be weaker than the parent metal. To say that is frustrating for engineers would be an understatement. Heat hugely affects the hardness of aluminum, and hardening it can be pretty complicated, and will vary by alloy, but certain alloy families are much more common than others, and if you know what you are melting down, you can probably guess what kind of alloy it is, to an extent. IE engine parts vs rolled bars, you can find out which alloy is usually used for which products, and work from there. Alloy families will have similar hardening processes, but iirc, most are precipitation hardening processes which require time, usually you hold a certain temperature for a recommended length of time, then allow it to cool.

    General points about aluminum though, regardless of alloy it tends to melt at a low temperature, but it has extremely good heat conductance, so it will generally be pretty easy to melt, provided you're hot enough. It melts well below the temperature of cast iron, so I'd keep an eye open for a suitable cast iron container, that should stand up decently to the heat you need. It will wear, but cast irons will likely wear less than steel for what you're using it for, as it SHOULD resist the heavy oxidation that steel would accrue. IE hot steel rusts before your eyes, but cast iron might tolerate this a bit better, depending on how much sulphur or phosphorus there is, as both will burn up at high heat. Sooo... aim for a cast container designed for high heat. I know of people using steel though, and certainly the right kind of pottery would work best (ceramics are very useful, but VERY easy to break when hot, IE a drop of sweat could cause a crack/explosive failure, so I recommend the cast iron).

    One thing to remember, aluminum oxidizes very, very rapidly, so it will form a skin. I don't think you can use an argon environment, but look up deoxidizers. I would guess silicon MIGHT be oxide easier, as it's widely used to deoxidize steel, but then, aluminum is used for that too sometimes, its that prone oxidation.

    Assume aluminum won't be very hard or strong compared to steel when you cast it, but if you get good at it, and use decent scrap, you might be impressed.

    Regarding the mentioned massive machete, I did make up an elm handle, and indeed, it did not break. I heated the bejeesus out of it with a heat gun, and sealed/filled cracks with hot glue, so it should be pretty stable. The handle worked well when I used it, but the steel needs significant stiffening... so I continue to cold work it whenever I have the chance.

    I am forging a knife as a gift atm, but my fire is clearly not hot enough for drawing out steel, so this has been insanely laborious, as I started with a scrap piece of Grade 8 steel that was pretty short and thick, and am drawing it out to about 5 times it's length. Almost done drawing it out though, which is pretty amazing. I use a 4lb hammer, and am pounding about as hard as I can, often with the cross-pein, rather than the flat hammer face, and I still make small dents only. I'm barely getting the darn thing red hot! I am glad it didn't fail/ crack yet, but I think I'll heat it with a torch and work it very hot for a bit near the end, but the extra stress, if it doesn't actually break it, will make the final knife better. It might end up a tad brittle, but its not going to be long, more of a short tactical blade. Shouldn't be an issue, it being too brittle, as you won't be swinging it like a sword/machete.
    JuliusBorisovmeaglothlolien
  • meaglothmeagloth Member Posts: 3,806
    edited April 2015
    Thanks, thats a lot of info. Working mostly with steel(very limitedly, but still) aluminum has always kinda freaked me out. It's so light. Its like how certain people just can't believe that airplanes can fly, even though they see it every day, on a smaller scale. It just seems slightly unbelievable.
    Anyway it seems I was able to push through that mental barrier and deal with it anyway. Like I said I'm hoping to collect some soda cans and try again soon. I'm always on the lookout for a permanent crucible as well. Im up for trying to cast a rapier crossguard, but I think aluminum will be pretty hit and miss. Everything is a learning experience, I guess.

    If aluminum doesn't turn out id like to try something like this:


    It's probably a littel ambitious, but some of the other things he's done with this microwave parts are just spectacular. I don't know if I'll be able to live without trying the arc welder. (image
    image
    [/spoiler]
    This is ok. It's a lot prettier and lighter(16ga) but the stainless steel wire, which I expected to be rather hard, I'd dead soft. I think. I might have to switch to aluminum, though it's much more expensive. But these rings are barely losing together. Also these rings are two small. This new one took almost three times as much time as it did to make the. 14ga bracelet.
    Here's the 14 gauge:
    imageimage
    Post edited by meagloth on
    JuliusBorisov
  • DreadKhanDreadKhan Member Posts: 3,857
    You SHOULD be able to find an old transformer-type buzzbox welder for cheaper than $100, as very little is done with stick/SMAW these days, at least professionally. New stuff is welded with Flux Core, or MIG, as both are much cheaper and faster. That said, if you want a decent Duty Cycle (thats the rating that dictates how long a machine can operate at a given load... its given as a % of a 10 minute window, at a given amperage or maybe wattage)... 20% at 120 amps DC is probably something you could find on a fairly cheap SMAW welder, meaning 2 minutes out of 10 you can operate at 120 amps without risking overheating/wearing stuff out. If you run for 2 straight minutes, that means 8 minutes not arcing is your required downtime. More expensive machines will tend to have better Duty Cycles, with industrial use and machines designed for use with a robot or traveler having VERY high Duty Cycles (usually 100% at a pretty high amperage).

    Big annoyance for the average person looking at getting a welder though is that pretty much any useful welder that isn't expensive will require a 230v plug, IE not a standard wall plug. If you use an Inverter type welder, you can definately find machines that can do what you are talking about while only using a 120v plug, but these are more expensive, as the tech isn't as old. Transformers have been used since arc welding started out, but transformers for SMAW haven't gotten much better for 50 or 60 years really. Hence them being really cheap if you're lucky!

    I suppose you'd want to use AC for something like this, and you might want to consider preheating stuff with an old fashioned fire before hand, but even a pretty weak arc (40 amps on a carbon arc should arc) will definitely melt steel. If you can run +100 amps, it will melt pretty quickly if it isn't pretty massive. I have tossed around in my head making a carbon arc furnace, though I haven't done it yet. Perhaps this spring/summer. Carbon arc furnaces are used in modern smelting industry, but they'd be much bigger. On the much, much crazier side, you might look up Atomic Hydrogen Welding... Its very old, and sounds kinda dangerous, but its an interesting process, and pretty hot temperature-wise I hear. Never seen it in action though. In my semi-professional opinion, I'd be worried about getting hydrogen in your metal, which causes sudden failures, especially in alloys with higher carbon equivalence... IE stronger alloys of iron.

    Stainless steel is as a rule both harder and stronger than almost any carbon steel... I wonder what alloy you're dealing with. Quick question, is it magnetic? If it isn't magnetic, that'd be Austenitic stainless, which is not typically as hard alloys lower in nickel... but it should still be much harder than regular steel. You need considerably more force to bend stainless sheeting for example. Well, I know stainless usually has more of a mixed nature for hardness, IE has very hard parts of its microstructure with soft parts, which is why stainless is not popular for stuff like woodworking blades; its harder to sharpen, yet doesn't hold an edge. Works well for machetes and the like though, where holding a true razor edge isn't important, or for disposable razors, where you won't resharpen.
    meaglothlolien
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