ThomasPowers Posted March 18, 2012 Share Posted March 18, 2012 Actually steel prods were used for crossbows that were spanned by a goats-foot lever or a belt and claw too. Very large crossbows were used for wall mounted siege weapons. One at the MET in NYC was 1100 pound draw; but only 15 pounds had to be exerted on the crannequin to span it! As Payne-Gallway mentions the biggest difference between a crossbow designed for hunting and one designed for war use was the poundage. Quote Link to comment Share on other sites More sharing options...
Ken Nelson Posted March 19, 2012 Share Posted March 19, 2012 There are a few key points to remember when dealing with springs, prods and blades. First, flex vs bend. When a piece of steel flexes, it moves from it's original shape a distance and then returns to true. In the flex range there is no damage to the steel, at least not until you start reaching 100's of thousands of cycles. Car springs and axels flex constantly and hold up quite well, but may eventually fatigue. Bending is what happens when you exceed this motion. the steel deforms permanently(takes a set) and is damaged. That piece will never be as strong again. you can thermal cycle it to relieve the stress and re-heat treat the steel, but it has also changed by thinning or stretching a bit. Second, the range of flex of a given piece of steel is determined more by geometry than heat treat. if you were to look at two pieces of steel, both the same alloy, length, and hardness, the thinner one wil flex further than the thicker one, while the thicker one will be more difficult to flex. Think of a 10" bowie vs a 10" fillet knife, or if you would like a more extreme example, 10" by 1" by 1/4" thick 1095 hardened and tempered to a RC 60 may flex only 40 deg or so before bending slightly and then breaking, while a 1095 shim at 10"x1"x.002" and same hardness may be rolled up on itself 3 or 4 times and still return to true. Heat treat makes more of a difference once the flex limit has been reached. A fully hardened piece say RC 65+ will snap and shatter if the flex is exceeded, while an anealed piece of the same alloy will bend quite a way before finally tearing. Cracks, micro cracks, and even deep scratches can play XXXX with flexing and bending steels though. the bottom of a scratch, or crack will act as a focal point for stresses, and can cause steel to weaken dramatically, or fail at ranges and pressures much lower than expected, often with dramatic results. Quote Link to comment Share on other sites More sharing options...
GeorgeLots Posted March 27, 2012 Share Posted March 27, 2012 Hello to everyone. As a newbie in blacksmith/bladesmith and for amateur purposes (for my own enjoyment) i started searching info on how to make swords etc and seen on the web that leaf springs could make excellent swords because of the elasticity they have. Reading this article now you guys made me anxious that i am tinkering in the wrong metal. I have some leaf springs that i got from a small truck (car size not the big ones) and i started working one a piece of them. They are a bit dirty and some rust on them but i grinded the surface of the piece to remove the dirt and it was smooth as i far as i could see. I am trying to forge it all the way, heating it to around 1800 F (orange colour) and forging and i would heat treat it when finished and anneal it also. Will there be still a problem with it? if it is a bad idea to procceed i might as well dump them now that i am on the early stages. Thanks a lot. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted March 27, 2012 Share Posted March 27, 2012 Will there be a problem? I'm holding a piece of metal---tell me about it's microstructure! How can we tell you about the state of the piece you have? So the answer is Yes, No or Maybe. The alloys used for leaf springs are generally good ones for swords. However we have no way of telling if the piece you have has been over fatigued. I've been driving for nearly 40 years now and have never broken a spring; yet I have friends who have broken several. You can't tell. If you worry about this sort of thing, get clean new metal of the same alloy! MUCH cheaper than to spend 80 hours on a piece and then have it fail due to a hidden fatigue issue. There are a number of commercial methods to find hidden flaws in metal; almost all of them more expensive than buying a good piece of metal. Note: "i would heat treat it when finished and anneal it also" translates as "i would heat treat it when finished and heat treat it also" Annealing is one step of heat treating that is usually done before grinding; normalizing, hardening and drawing temper are other steps in heat treating. If you are in the USA you can go to your local public library and ILL a copy of "The Complete Bladesmith" by Hrisoulas that should help you immensely in getting started bladesmithing. If you are not in the USA It would be well worth your while to track down a copy anyway! It's funny how over a hundred pages written by a master of the subject can turn out to be a lot better than a dozen pages on the web written by who knows who. Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted March 27, 2012 Share Posted March 27, 2012 1800F is too hot, try a cooler temp red to orange is fine. You do have the correct steel. but use new steel it only costs about $2.50 to $3 a pound. Getting steel is a lot like beef: a dead cow laying in the sun for a day is still beef, but not quite eating quality, that is the same problem with used (maybe abused) steels. Quote Link to comment Share on other sites More sharing options...
Rich Hale Posted March 27, 2012 Share Posted March 27, 2012 The key to yoiur question here is that you are just starting: In my opinion, (for wot its worth) Sords are not a starting point. If you wanted to be a mechanic and work on engines would your first try be to pull the engine out ot a new corvette and disassemble it? It is kind of like that, other folks on here may say just go ahead and begin anywhere you wish and don't look back. You may have inborn talents that will allow you to just make a wonderful sord without learning any of the basics. I have never heard of anyone able to do that yet,,,lol If youi wish to make sords start with knives. Learn all of the heat treat and forging skills, If you have a blade that does not work out you are ouit a days work,,a sord on the other hand, you may well have spent every waking hour for a few months before heat treat. And likely the failure will be linked to lack of basics. You and others may have differing opinions..just have fun! Quote Link to comment Share on other sites More sharing options...
MattBower Posted March 27, 2012 Share Posted March 27, 2012 Although I'm generally in the camp that says it's not a good idea to start with swords, it's probably possible to make a safe, reasonably functional sword with almost no experience -- with close instruction and supervision from an experienced swordsmith. If you have one of those around, and he's willing to take you under his wing, that's a special case. Otherwise, it's probably wise to start with smaller blades and work up over time. Quote Link to comment Share on other sites More sharing options...
jmccustomknives Posted March 28, 2012 Share Posted March 28, 2012 It may be just me, but every modern leaf spring I've ever delt with was 5160. They included everything from a '77 farmont to a late model f250 4wd and several trailer springs, even ones from a coal hauling trailer. I do understand that from the mid '70's back they were 9260 and some extra heavy duty truck springs (peterbuilt, freightliner...) could be 6150. Finally, I spoke to a gentleman who works in the steel industry. He said during the late '80's and early '90's they supplied GM with 50100 for thier truck springs. I haven't gotten my hands on a set yet, but have a few scrappers looking for me. Offer a free knife and you can get a lot of springs thrown your way. Quote Link to comment Share on other sites More sharing options...
GeorgeLots Posted March 28, 2012 Share Posted March 28, 2012 Well yes i get the point that we cannot determine the structure and the materials in the piece of metal of the leaf spring that i have. I have read the book of Jim Hrisoulas you mentioned and found usefull advices. The thing is that am not a professional blacksmith that just started his shop. i am doing this only because i have a great love for swords. If a sword construction fails on me i dont really care to do something else. So all the info is on the sword making that i wish to know. Yes i thought to try and make a knife 1st to see how it goes and how the steel will come out, but i am so anxious to make my own sword. Anyway i suppose the best thing is to buy a new piece of 5160 or 1060 steel to work with or get the piece i have to the phamatografer to analyze it and see the materials it has. The other question now is how can i see if the fatigue limit is passed?? Quote Link to comment Share on other sites More sharing options...
jmccustomknives Posted March 28, 2012 Share Posted March 28, 2012 Early on I bought a peice of 5160 to test with and compair to the springs I have, they were identical. From everything I've been told and from experience most automotive and truck springs today are 5160 or some version of. The problem with sword making is the heat treating, it is most difficult to get the heat even through the entire blade. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted March 28, 2012 Share Posted March 28, 2012 Well in 32 years of smithing I have run into *one* low carbon strain hardened leaf spring---would not harden even in a water quench. So it's possible to find others out there. How to tell if it's fatigued--as I previously mentioned 1: if the piece is already broken or 2L using one of the expensive commercial methods looking for flaws---that should only cost several times more than just buying a new known good piece! And George the *fastest* way to learn swordmaking is to learn to smith FIRST so that you only have to deal with the blademaking aspects rather than dealing with basic smithing issues as well as blade specific issues. If you lived in the USA perhaps you could take some of the American Bladesmith Society classes. I spent a year apprenticed to a swordmaker, 6 days a week in the shop, no pay but 2 meals a day with the maker's family, etc. So when I say that learning to walk before you enter marathons is a good idea I do have some background to base this on. Even learning to grind is a valuable skill before going on into blades. One of my students just had me go over some blades he was working on and was quite sad when I told him that one of them was past saving and should be cut up and added to a billet as it was made from a pattern welded billet but had gotten too thin as he was still learning grinding. So here he was forge welding up nice pattern welded billets but still behind on finishing skills and so wasting a lot of time and effort expended making the billet. Quote Link to comment Share on other sites More sharing options...
Rich Hale Posted March 28, 2012 Share Posted March 28, 2012 George, I think the thing for you to do is make sords. Used steel, new steel, wotever you prefer. Cut, pound, grind away and learn all you can. If you spend a ton of time and produce steel dust and scrap metal then just think of that as tuition in you search for knowledge.I would bet there are a lot of folks learning sord and knife making that did just that. In fact if you look back to the dark ages, (before computers) That happened a lot. Folks couild not just sit and type in a question and get great answers to guide the learning and maybe shorten the toime frame a lot. Local clubs did not exist and we could not attend meetings and see how to improve our skills and knowledge from those doing the demonstrations. Books like those mentioned above were not here. Some of the old books were there but then no one told us about them. In my area there was no one to go visit that would share any information with us. They had it they kept it. I do not know how to research the information but a wild guess is that most sord makers trying to learn in that environment just gave up and quit. Keep us posted on your progress and post pics of your work..and have fun! Quote Link to comment Share on other sites More sharing options...
GeorgeLots Posted March 28, 2012 Share Posted March 28, 2012 well thanks everyone for their advices and comments. you were all very helpfull .i am not in the US so no bladesmith around to teach me anything.I am doing this for my own pleasure and i love the feeling of the forge and the hammer trying to shape the metal. I hope i will finally reach my goal and satisfy myself :) Thanks everyone. i' ll keep you posted on any progress i will have. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted March 28, 2012 Share Posted March 28, 2012 Where are you? I know bladesmiths in Canada, Mexico, Brazil, France, England, South Africa, Australia, Germany, Austria, the Netherlands, Ireland,.... Quote Link to comment Share on other sites More sharing options...
GeorgeLots Posted March 28, 2012 Share Posted March 28, 2012 i am in Greece :) no bladesmiths in my town for sure. only shops that sell kitchen and butcher knives and some hunting stores.. If i will do anything i will do it by myself that is for sure :) Quote Link to comment Share on other sites More sharing options...
JPH Posted March 28, 2012 Share Posted March 28, 2012 I see ya made it...these guys are a bit passionate so... Anyway I'll help ya all I can... JPH Quote Link to comment Share on other sites More sharing options...
GeorgeLots Posted March 28, 2012 Share Posted March 28, 2012 thanx a lot Jim :) Passionate or not all of you guys are a treasure vault to someone like me that is looking anything he can grab on to :) Cheers to all !! :) Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted March 28, 2012 Share Posted March 28, 2012 Knifemaker's in Greece: http://www.fokidanet.com/akknives/ http://experiencegreece.tumblr.com/post/16968113615/knives-from-the-homeland Hmm Crete still seems to have a few too... Quote Link to comment Share on other sites More sharing options...
GeorgeLots Posted March 29, 2012 Share Posted March 29, 2012 Thomas thanks for pointing those two out :) didnt know that we had knifemakers in Greece besides Crete. BUT i say again in MY TOWN there is none. I cant leave my job and my family and move south 500kms or more to become an apprentice of these knifemakers. all i can learn is some basics on blacksmithing from blacksmiths in my area (if they are willing to learn me) and the rest on bladesmithing to learn from books, web and myself. I appreciate that you are trying to protect the new starters from making terrible mistakes and waste their time and work but this is something i wanna do. It's like someone that wish to do a skydiving and his friends say " it's dangerous and what if you wont open the parachute etc etc " but he still jumps from the plane. I wanna tinker along and find out what i am capable of doing with the forging. Who knows i might be the next one to pick up the lost art in Greece. North Greece Kozani. if you check the map of Greece and see Kozani and Fokida and Athens and Crete you will understand it's not easy to just pop up on the store of one these guys and learn his work. I am alone in this place and my teacher is the web and my own skills. Thanks for your concern though. Cheers. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted March 29, 2012 Share Posted March 29, 2012 However I have found that even spending a weekend with a trained maker can cut 6 months off your learning curve. Who knows perhaps you could correspond with them or ask them if they know of a bladesmith closer to you that perhaps is not on the internet! Of course here in the states we are a bit more blase about distances. I'm traveling 166 km (each way) just to visit my Doctor today and when I go to the large smithing convention Quad-State it's 2500 km---each way! Quote Link to comment Share on other sites More sharing options...
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