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A. Humphrys

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About A. Humphrys

  • Birthday July 8

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    Roanoke, VA
  1. Awesome photos Jesus, I really hope these tuyeres are just what you and Denis are looking for. I had a lot of fun working on the project. One thing Jesus did not mention is his seemingly unending patience. Denis and Jesus handed the waxes over to me just over a year ago. I smoothed up the waxes, gated the tree up and got it ready for coating. Long story short, an equipment problem set us back and then my wife had a baby and I fell off the face of the earth. Peter Kim took up the torch, and fit the project in between his thesis, getting the coatings on, burning out, touch ups, and finally pouring. Throughout the whole process Jesus has been extremely patient and understanding, and I cannot speak highly enough. I am extremely happy these turned out in the end. The video kind of sums up some of the best parts of my college career, induction whine included. The VT FIRE program is the foundry branch of Materials Engineering department and is probably one of the most hands on programs in the entire college of engineering. I am extremely fortunate to have taken a local job with strong ties to the program. I had no idea that sword was still there. The cast iron sword was made by a student last semester as his final lab project when his first project went south at the last minute. I don't want to hijack the post, but I thought you guys would enjoy a picture or two of the original. The blade was made for the TMS Bladesmithing competition early in 2015. A group of students, including my longtime friend Peter, asked me to lend a hand with the pattern. They gave me a drawing and some rough dimensions and I did the best I could. They proceeded to pour, cold forge, file, polish, mount, and finish all on their own. This year I believe they are setting out to make an alloy in the foundry of the same chemical composition as meteorite steel and forge a blade from it.
  2. Scott, I would launch that bodkin any day, and I wouldn't ever think to question if it was your first or not. What diameter stock did you start with and what size shaft does it mate up with? Keep it up! You're making me want to go build one myself!
  3. http://www.bladesmithsforum.com/index.php?showtopic=17294 When I first started experimenting I used something like this. Though I have to admit the one in the thread is much nicer than what I built. I made do with it for a few months, but as my interest picked up I moved to something a bit larger that runs off a large propane tank, the little guys add up quickly and they freeze up after too long. Adam
  4. Wow...now that's just gorgeous. Don't keep it all to yourself for too long! Can't wait to see the full photos. Is it a Nagamaki?
  5. Oups! Count my words out Caleb. Wrong alloy, wrong quenchant. It's already been posted, but oil is the way to go with leaf springs. Without knowing the chemistry, its hard to peg the exact alloy but most people I've talked with treat it as 5160. 5160 is an oil quencher in the knife world. The Pearlite nose graph is a good one to know. It goes by a couple of names and the best results are found using "triple T graph" "TTT Graph" or "Isothermal Transformation Diagram" this tells you what to expect when you quench at a certain speed. For this case, in order to get past the "nose" you have about 4 seconds to go from 1550F to below ~900F. If you can manage that and continue cooling at an appropriate rate then you should end up with a fully hardened knife. The horizontal line marked Ms is your martensite start temperature, about ~475F. This is the temperature that martensite starts forming. Get down to about 400 degrees and you can maintain this temperature for hours (days... weeks... I'd have to look) and still be hard. That being said, you'll be looking for something a bit more spring like than glass hard. If you don't let your sword reach room temperature for a while then you end up tempering martensite as it forms. It is still a good idea to do a separate tempering run after cooling to room temp.
  6. Did I read right that this is 1080? If so then you're probably not going to like your results from your oil/wax mixture. You're going to want a very fast oil, a brine, or water quench. You have under one second to get your sword from 1500F to under 1000F in your quench for full martensite transformation. I do not think your mixture will get you there. Best, Adam
  7. I used to be Rob! Wish I still was. I shot for about 12 years before I hurt my right wrist. Don't really remember how I got the injury but the three finger release has a tendency to make the damage worse. I haven't shot in about two years. Before I got hurt I was working on learning to shoot English warbows. I had trained myself up to about 75 at 31" before I had to stop. My wood shop is still full of bow building supplies and tools and more arrow components than I know what to do with. I have two boxes of peacock primaries that I'm sure the moths will get to before I do. Mick I had a laminate similar to yours on my bench when I had to stop everything.. shaved a number of pounds off her and gave it to a member of the college archery club. I never did get the hang of making horn tips, the one you have sure is beautiful. That being said, I've been slowly rehabilitating my wrist in the hopes of starting again. Might just get around to building a little 30lber if I find the time. Adam
  8. Oh man.. Gotta wake up the zombie thread! Well I have a mixed update. Good news is that the iron anvil is alive and well and currently being used by some summer research students. The steel anvil... well lets say attempt two is in the future. The short pour dictated taking a bit more off the top than we had anticipated, meaning that some unlucky lab help will be getting friendly with a grinder and the horn at some point in the future. As for the steel anvil, half of it worked. The other half ran out into the pit. To make a short story shorter, the mold got abused a bit between molding and pouring. there were some minor fitment issues with the halves that resulted in a run-out from the core print for the hardy core. But, we did get a good pour shot. We'll melt it back down later and try again. You can see I lowered the base of the anvil on the steel attempt. Jerrod, I went with the risers on the face for a number of reasons. The first being the lack of a way of removing a riser from the side of an anvil. With the risers on the face I can get bandsaw in and take them off close to the face. Then its a few passes on the surface grinder to true up the face and base. The segregation is a concern, If i were to approach that I would most likely mold the anvil upside down and gate through the feet, and create a flat base at the same time. I would have to alter the flasks a bit to account for the higher pressures since run-out is obviously a concern on this one. If I were to make another pattern I would probably gate in through an upsetting block and horizontally part the mold. That way the feet wouldn't get in the way of cutting the riser off. Might make coring in the hardy a bit more straight forward.
  9. John, I'd just about kill for a shop like this of my own. That said I couldn't afford to run it for more than a month. I'm grateful for every chance to work with VT's facilities now that I'm an alum. Bruce, 8620 makes some great base material for other steel alloys. But in the end you might be correct. I don't have my technical books in front of me at the moment, but i doubt that 8620 quenches too hard. I seem to remember it has some cold work potential though.. But don't hold me to any of that. As for induction hardening... I'm going to leave that to the experts.. and the guys with the cool induction forges. And here's the reason why.. a high power induction forge runs at 25 kVA which is equal to 20kW. The induction controller pictured above runs at 125kW. The leads that run to the coils are braided copper about 1 inch in diameter and you must be a certified electrician to even open the case. In short, it's far too much power for me to mess with. That said, there is plenty of power to get the job done. The alloying supplies are in route. We should be back at it some time next week. I will try to get more detailed photos of the molding process and the pouring process.
  10. Thanks for the kind words gentlemen. As I said before, Anvil morphology was not my strong suit.. it didn't even occur to me that I had cut the base in too deep until I went back and looked at my drawings after casting the sample. The bright side on that is it helps with the directional solidification... which lets me get away with our riser configuration. I think I can make it work though. If I do this again, it will be much smaller of an arc if at all and yeah, I think I would go well beyond the typical anvil. The picture below is the hot side of the foundry lab. The cold side contains all the sand equipment, investment equipment, finishing, small heat treating ovens, and the metallurgy lab. The hot side is where the really hot stuff takes place. You can see some of it in the picture. We're gathered around the 300lb tilt furnace for a ductile pour, you can see the treating crucible under the torch off to the left. Behind me (the guy on the left) is the lift swing furnace, this takes conventional crucibles and is what we do all our copper base and some aluminum out of. Both of these furnaces are induction and the power unit is the big blue box on the right. Between me and the next guy you can see our normal aluminum furnace. Where the crucible is heating up is our pouring area, the cream colored structure above it is a dust collection system. That system is also attached to every piece of equipment in the building and keeps the air extremely clean. And the little yellow control pendulum is for the overhead crane. Out of picture, behind the photographer is the de-waxing oven for investment casting. Its a monstrous natural gas furnace with a 4ft cube chamber. We chose A2 for a number of reasons, and while it may not be the best, it has some things going for it. On our side of things A2 isn't all that expensive, that being said we're looking at an modified A2 with higher tungsten and lower vanadium to make better use of what we have. For us, about 900lbs of A2 runs about $150 plus scrap prices. Ferromolly is what costs, and other alloys take considerably more than A2. Second, A2 is air hardening. While we have everything you could think of to make something hot, what we don't have is quench tanks or a good method of handling super hot castings. We have plenty of fans though, and I think I will end up casting a very large aluminum heat sink to quench the face. I think that it is far safer and more feasible for us to make A2 work than it is for us to venture into untested territory on the quenching side of things... our de-waxing furnace is more than capable of reaching austintizing temperatures and should suffice for both annealing and hardening A2 albeit is a bit wasteful. Alan, the horn is a bit more of a block than it should have been. You can see in the picture of the mating mold halves that the very top of the mold broke out. This happened when we stripped the pattern from the mold, and while its a bummer to have to grind it all back, it looks worse than it is. The rest of the horn came out very well with the exception of one spot on the opposite side where an extra screw had to be added and left a nub. The hardie will be cast in place, and possibly the pitchel as well. I'll use a sand core dipped in core wash which should cut down on metal penetration into the cores. That will save us the headache of trying to bore and broach. My goal is that the run in A2 will only need the face and horn ground before it is ready for heat treatment and use. I hope to have more for you all before too long.. though I have the feeling it will be at least 2 weeks before our supplies arrive. We're completely at the mercy of our alloying elements being delivered.. That said I do have a line on a couple hundred lbs of 8620 that apparently is good for anvils. I would have to outsource the heat treatment though. Dave, At this time, no... but I am trying... I want anvils too....
  11. I've been a lurker here for a while, but I figured my latest project might just be worth sharing. I hope you all agree. Just a bit of an introduction. My name is Adam Humphrys, I'm not much of a bladesmith, but I'm hoping to get better. My saving grace is that I'm pretty decent at casting things. I graduated from Virginia Tech this year as a Materials Scientist and Engineer, going on to get a job as a metallurgist for an engineering firm. That said, one of the best parts of my education, about two years of it, was participating in the VT FIRE program. (Foundry Institute for Research and Education) The firm that I work for is very closely tied to the program, and as such I keep in contact with my professor and a number of student whom are still there. Every now and again I get asked to do something cool, or assist with something cool. This project is one of those times. In one of my recent discussions with my old professor he brought up a research project on forged materials. Specifically a forge weldingproject proposed by another engineering discipline. That's all well and good, only trouble was he didn't have an anvil. Now us being foundry guys, well we think that's something we can take care of. And so the quest to cast an anvil began. Now, I mentioned I'm not much of a smith. Furthermore, I've always been a bit of a broke smith, so my anvils have always been scrap blocks of steel. As such I know I made a few mistakes in general anvil morphology, but I hope they are forgivable. That out of the way, this is where we started. This little sketch and CAD gave us a general idea of where we were heading, about a 130lb anvil. So far it’s a more proper anvil than I have ever had. And with a drawing in hand, I moved on to building some patterns. Now there are a number of ways to go about this part, you can basically make patterns out of anything. For me, I choose some nice sheets of MDF. Specifically one sheet of 4'X8'X0.75” and one sheet of 2'X4'X0.5”. I prefer MDF over wood and plastic for only a handful of reasons. The first reason being that I can use it for the pattern, the match plates, and the flasks. The second being the uniformity of the material and its relative ease of shaping with simple tools. First thing I do is make a pattern of the silhouette of the anvil out of the 0.5” mdf. I make this slightly over sized and use this to draw out duplicates on the other sheets. You can see it laid out below. The anvil body is made of 4 layers of .75” and 2 layers of 0.5”. When you put the thinner sheets at the center of the stack you end up with a 4” thick body that splits evenly into two 2” thick anvils. This helps me later on when we get to molding this up in sand. Two pairs of front and back feet from 0.75”; sheet finishes up the raw materials. I screwed the body together in two halves with two screws holding both halves together. I didn't attach the feet right away so I could true up the sides on a disk sander smooth out any inconsistencies left by my bandsaw. The pile of anvil pattern parts is below. Once the sides are trued up I glue the feet together. Now before I put them on the anvil I took them to the disk sander to make a nice smooth transition from the foot back to the main body of the anvil. Once the feet have been contoured they get glued and screwed to the anvil and a few pins to keep everything from wiggling loose later on. (You might be surprised how much abuse a pattern can get in a small research foundry...) A little work with a rasp on the horn and you end up with something that looks like this. Close enough to be considered an ASO right? Well aside from the woody consistency.. it’s all about potential... Now never being someone to leave something well enough alone.. I took a bit of creative license and added some artwork while I smoothed and patched some holes. For that I picked up a Fix-it Stick at the local hardware store. It's a two part epoxy clay stick that is filled with steel powder. I'm pretty sure they make a similar product with sawdust instead of steel, but this is what I could find. I mixed the stuff up in really small pinches and worked it into little cuts in the anvil, then I would carve it back to make my designs or to even out patched up holes. When the stuff cures, it cures very hard. It can be scraped and filed, but after it cures it can't be carved so you have about a 10 minute window to get the work done. Below you can see my stencils and what I ended up with. One side is a phoenix of mine, and the other is the program logo. I guess you could call the bird my maker’s mark of sorts... Now nothing is perfect... but man I sure spent way too much time trying.... And now the gritty part, sand molding. (I have a problem... I know...) This particular project uses a three or four part mold. It consists of two molds that house the anvil, a third that makes the face and holds the risers called a cheek core, and the fourth is the core for the hardie hole. We left the hardie hole out on our first pour as this first attempt is to make sure we don't have any glaring casting issues. All of these parts are made with a no-bake sand system. No-bake is basically sand mixed with epoxy. You dump it in, pack it in, let it set, pull the pattern, let it cure, then pour. It’s a pretty easy process to get used to, and much easier to move around than greensand molds. Below is a picture of the flask for the cheek core. The two tubes in the center are insulated riser tubes not that different than a compressed fiberwool. Below that is the first half of the anvil mold. Same type of flask as the cheek core, except instead of the riser sleeves we put half of the anvil pattern at the bottom with the face pressed up against one wall of the flask. In the second picture you can see our sand mixer. The bright yellow nozzle is where the mixed sand comes out and the table that the mold is sitting on is a vibratory table. This along with a bit of elbow grease gets the sand packed and settled in quite nicely, and provides a very nice surface finish and high detail. When the above mold has set, its striped from the flask, and the pattern is removed. The second half of the anvil pattern is screwed back on to the first and the pattern is replaced into the mold. The mold is placed back into the flask with the pattern facing up. New walls are put back on the flask that are double the height of the ones above (12” vs 6”) Some notches are cut into the first mold (for realigning later on) and talc is dusted onto the mold. Then the second half of the mold is made directly on top of the first. This is the easiest way for us to get the best fit and alignment on our molds. You can see them with the patterns removed after molding. If you look there are some fins that stick out of one mold that line up with the notches in the other half. Also notice the cuts on the outside of the mold.. These things are heavy and every bit helps when trying to get fingers underneath. The second photo is of the two together. Now I have to confess... I was not present when the students poured this mold.. So I'm missing all the great action shots. That being said, we will pour again and I'll try to do better next time. Below is how the complete mold looks when it's fully assembled. If you notice the dark areas, that is burning/burnt epoxy binder. Stuff stinks like crazy, but when our dust collection is on you can barely smell a wif of the stuff. I digress. You can see the two larger molds at the bottom, these are clamped together with angle iron and all thread. On top is the cheek core weighed down by ingots, and on top of that is a pour basin with a filter held on by core paste (glue.) This picture was taken about 24 hours after the pour. What photos don't show is that this puppy is still smoking. For the test pour the anvil was cast in ductile iron. Our ductile iron pours are limited to 125lbs due to the nature of magnesium reactions and the size of our crucibles. That said we weighed our pattern and estimated a finished casting weight in iron of 116lbs. Close but we gave it ago. Now for the Christmas morning sequence... Aaaaaannnndddd....... Now as I said before... nothing is perfect, but I tried. And for a test, we did alright. Sadly, the casting ran short. There is exactly 116lbs of iron in that casting, apparently the remaining 9lbs that were melted got lost in slag. As such there was not enough to fill the risers and create enough pressure to fill the corners of the face. You can see some minor shrink where the risers would have been. Live and learn... and then pour them in A2. Our plan now is to make another mold, and pour it in A2. Our furnace can melt up to 300lbs of iron or steel, and when we don't have to magnesium treat it for ductile iron, we can pour it all straight from the furnace. That is just what we will do. At the moment we are at a bit of a pause in the project. We're waiting on ferrochrome and ferromoly to make our batch of A2. We might have to substitute tungsten for vanadium, but that shouldn't affect the behavior of A2 too much. A couple of other mistakes reared their heads so far, and will be addressed before the next pour. As I mentioned before... I will do my best to get you guys some action shots when we move to steel... casting steel gets downright exciting... I hope you all enjoyed this.. and more to come down the road (maybe days.. or weeks) Adam
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