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Copper tuyere casting (a bit more high tech than my usual)

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A couple of years ago Adam Humphrys, a member of this forum, approached me about doing some bladesmithing/metallurgical project. Adam works as a metallurgist for Dominion Metallurgical and graduated from Virginia Tech. The company maintains a working relationship with the university as they sponsor student's projects. With the help of graduate student Peter Kim and professor Dr. Alan Druschitz director of VT FIRE which is the reasearch foundry at the campus we thought of making a copper tuyere by casting. I had never previosuly considered doing this large size project at the shop because of need to make new tools and equipment. The fact that the foundry was more than well equipped for the task solved the problem.


I talked with Denis McAdams about this. Over the next few months Denis turned the wooden shapes in the lathe and made the forms from those. We were on our way.


This is the SolidsWorks drawing that I made to get us started.




And these are the wooden forms and wax that Denis turned.








This is the sintered silica mold that would be used for the pour. It cracked on one side during the burn out of the wax due to expansion of the wax but it was repaired without a problem. It is sitting inside a 3-4 cubic meter natural gas blown furnace. The blower for this furnace is 4 times the size of my welding forge.




And these are a couple pictures of one the induction furnaces at the foundry. I forge the exact voltage 125,000 Kwats. I am probably wrong. Adam can correct me. The fact is that it took just a few minutes to melt the entire charge of the crucible which weighed over 70#.










Yes. The astronaut suits were mandatory. The copper was of high purity (over 95.5% copper) in order to improve the conductivity. The screen reads the temperature of the molten copper.

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This is a video of the pour.





Apparently I can't link to the video file, so copy and paste the above.


Maybe one of the administrators or someone more savvy can fix the video link or embed it.



Edited by Jesus Hernandez
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Dunno what's up with the linking, I can't get the buttons to show in the editing box.


But, COOL! Or very hot, but neat-o. Can't say I like the whine of the induction unit, but I can't argue with the speed and cleanliness.

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Way cool! That's an exciting opportunity that you have and the resources available over there. I'll be looking forward to see them in action!

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Jan, The inside dimensions are a compromise between what I wanted to do (start at 1/8" wall thickness at the back end and end up at 1/4" at the mouth while making something that the experts at the foundry felt will make it through the pour. I seem to recall some limitations imposed by the making of the wax model as well. Denis can talk about that. I also wanted the back end to connect to standard dimensions pipe for plumbing to the air supply.

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Alan, the whining was loud but at a pitch easier to stand than my forging press hydraulics. In the end the result was worth it.


Here is another project of Adam and Peter at the foundry. I am not sure Adam knew I was going to show these but here it goes.






It is a cast iron leaf sword. The wood work is Adam's handiwork. The original blade was cast in bronze for a school project.

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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.





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