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Hello all, First post here to show some results of experimenting with the slip casting of aluminiumoxide (alumina). https://en.wikipedia.org/wiki/Slipcasting Got interested to make shapes with refractory oxides by the posts of MonkeyForge and Mellin although they were using zirconia and veegum/bentone and were forming the mass by hand. Zirconia is a little too expensive to mess around with so i went with alumina. Using a combination of digitalfire.com, wikipedia, google patents, google scholar I found a lot of info which I all read. But a lot of it was above what was achievable at home. And a lot of it is about achieving the "perfect" results. I just want a useable result... So... what did I do. I already had some alumina-bentone clay (97%/3%) because at first my idea was to make shapes by hand but I found that really difficult. So I made a batch of slip from this clay by adding lots of water and mixing it with a blender. Aiming for a consistency of heavy cream as was mentioned on DigitalFire. This I poured into a simple plaster of paris mold made out of a plastic drink cup. It worked but was incredibly slow in forming the walls. The plaster was sucking in the slip very fast at first but after a millimeter or so it slowed almost to a stop. Dried my plaster mold in the oven and tried again, same result. Not great, not terrible. Remembering what I read somewhere that bentonite has a "problem" with releasing water. The bentone in my slip was creating a layer and allowing almost zero water through. Created a new batch with 99% alumina and water. Poured into my plaster mold and behold incredible fast wall forming. Now almost too fast to keep the mold full. It dries really fast in the mold and releases itself from the mold walls within a couple hours. Then let it air dry for a couple days. With this succesfull "recipe" I made a larger batch of alumina slip, specific gravity was around 2.40 and the bucket was really heavy. But the slip was still really fluid. It will settle if you leave it sitting for a while so you have to mix it good before use. Also made a mold for a crucible and a burner head. These can be seen in the pictures I added. The crucible was some random cup I found somewhere and the burner head was 3D printed. Also 3D printed a hole pattern as a guide to drill out the holes in the burner head when it was dry enough to handle. The crucible I have not fired yet. The two burner heads are already fired and 1 of them sintered well because it has a nice ring to it when you hit it with a metal item. The other one is strong but has a somewhat empty sound when you hit it. I didn't really had a procedure to fire them so maybe that's the problem. I fired slowly for 3 hours to about 1000 degrees celsius and then went full power for about 1,5 hours, no idea what temperature, then slowly back to 800 degrees in about 3 hours, then i turned off the burner and closed up with ceremic blanket to cool down during the night. Measured temperatures were at the exhaust of my furnace (my thermocouple wire will melt inside). I hope the inside reached at least 1200 degrees celsius. (Using natural gas and a forced air burner) The same method can be used to cast items with zirconia, magnesia, etc. But you will need a higher temperature to sinter it well. Hope you guys can use some of the info and use it to create more cool stuff.

I'm building my first forge and I sort of want to go for something all-in-one here. The hope is to be able to have a multipurpose system that can use solid fuel or propane injection, have the ability to be both forge and foundry, and also to be utilized for my glass blowing. I think I'm on to something here but I was hoping for some feedback from those more experienced. Not pictured I plan to also build a door for the front of refractory brick or cast o lite (or similar material) to close the forge up for smelting. Things I'm not sure of : 1 the shape of the mobile table in front 2 the necessity of the bottom mounted blower in the forward table 3 is this even feasible... I'm really not sure.... I really appreciate any advice you can give.

I've been asking myself what I would use to up the Ni in crucible steel if I wanted to make my own high contrast crucible steel damascus. I'd like something high in Nickel, and low in everything else, so I was looking at SAE 2515. In what kind of applications would this be found as scrap? Roller bearings? Other suggestions? I doubt I can find any FeNi or pure Ni locally. And I haven't been struck by any meteorites lately. We are the knights who say Ni!

Hi everyone, i have a freind who went to an auction and bought about 30lbs of silver cutlery, mis matched sets and broken peices, most is solid silver but there is some that are plated copper, my question is what kind of set up would i need to melt it down? and what would happen if i melted down the plated? would the two metals seperate or would they act differantly? thanks Josh