Casting aluminum ladles - GIF

[nova_robotics]

As for melting chips. Unless you have seriously compacted them into some solid form have fun with that. So much surface area for oxide to make your life hard. If you have a press and a way to make hockey pucks you might be able to make it work.

Inert the atmosphere with some argon? I have a bottle of pure argon for tig and another bottle of 75% argon + 25% CO2 for mig. I have an electric kiln that seals up fairly well so I'm not too worried about air leakage.

[Frank S]

In melting any aluminum if you had a way to slowly stir the liquid near the bottom and inject pure Argon not only will this help to reduce the oxides but will cause the hydrogen molecules to be absorbed in the Argon bubbles and rise to the surface where it can be removed with the draff. This will aid in degassing by removing the hydrogen and other impurities, also will help to reduce porosity and shrinkage of castings.

[nova_robotics]

This will aid in degassing by removing the hydrogen and other impurities, also will help to reduce porosity and shrinkage of castings.

That's a good point. If I ever get some motivation I might try putting a hose and a quick connect on my kiln. It would be interesting to try, at least. But I also don't know what I'm doing. I've never cast metal before. Watched plenty of Youtube videos on the subject. Kinda like reading a book on how to swim.

[Frank S]

That's a good point. If I ever get some motivation I might try putting a hose and a quick connect on my kiln. It would be interesting to try, at least. But I also don't know what I'm doing. I've never cast metal before. Watched plenty of Youtube videos on the subject. Kinda like reading a book on how to swim.

Here is the rub. the Argon needs to bubble up from the bottom of the crucible or cauldron at a slow pace. One thing you can do is to use a tube made from just about any metal which will not sluff off anything at the melting temperatures of Aluminum. If you have a way to slowly stir the molten aluminum so much the better as the bubbles from the argon will be distributed more evenly and will absorb more of the hydrogen molecules as they rise to the surface.
So there is your challenge stir the pot inject Argon and not bubble molten metal all over the place. If you have a cauldron capable of say a 40 lb melt a rotating stir tube with vanes on the bottom with a high temp rotary swivel at the top to blow the argon through you should be golden The RPMs might need to be varied between 150 and 250 or so this all depends on the depth and the amount of metal being melted. The Argon flow and the amount of time required to achieve bets results Just think of it as stirring very hot paint you can dip out the amount of metal for your pour with ladles or if a crucible use tongs to lift it out and pour.
The biggest factor here is I can't stress this enough since for most things I don't wear much of it that is PPE and be safe never put your face or any other part of your body directly over the molten metal use every safety precaution you know and even those you don't know. Also water is explosive in any molten metal

[mwmkravchenko]

YouTube OlFoundryman. Best teacher I have seen for aluminum casting.

What I am referring to is each chip is coated in aluminum oxide. This is tough stuff. And doesn't melt. I forms a bag holding the molten aluminum. Try something else. And save yourself the grief. Cast with aluminum that has been formulated to casting. No cans, no extrusions. Think rims, engine heads. Then you will have some success. It is true that for ideal casting you have to bubble argon through your molten metal, and molten aluminum and stell of any kind is a big nono. Molten aluminum dissolves steel and iron. So you need a crucible. Melt it and pretty much as soon as it is melted you pour it. The hows and whys of pouring are covered well by Martin in his last video.

[hemmjo]

It's a beauty. And it seals really well too. No flash at the seam between the two dies. I have piles and piles of aluminum chips and would love to try my hand at aluminum casting. And this guy seems to be doing it right.

I have not had much success recovering much usable material from aluminum chips. My furnace is electric.(Electric Crucible Furnace Update) My crucible, a 9" piece of 4" Sch 40 steel pipe with a steel bottom welded on. a It holds about 9 pounds of melted alum with out spilling all over. I tried reclaiming about 20 pounds of chips. I began by packing the pipe with as much of the chips as I could pound in. During the melt there was a lot of "smoke" or fumes, I am guessing from residual cutting fluids etc. I should add, the chips were mostly from machining castings from pops cans. I only get about 6-7 pounds of ingots from 10 pounds or cans.

I was expecting the chips to fall as they melted, but they did not move much at all. Using my stir rod, 3/8" rebar. I poked at the chips, they were just a spongy mass. It did shrink a little and I added more. I got very little liquid aluminum from what I tried to melt. The process, as I tried it, was not successful at all.

I am thinking the thin chips were mostly oxidized aluminum from the heat of machining which I am unable to convert to usable casting allow.

[hemmjo]

YouTube OlFoundryman. Best teacher I have seen for aluminum casting.

What I am referring to is each chip is coated in aluminum oxide. This is tough stuff. And doesn't melt. I forms a bag holding the molten aluminum. Try something else. And save yourself the grief. Cast with aluminum that has been formulated to casting. No cans, no extrusions. Think rims, engine heads. Then you will have some success. It is true that for ideal casting you have to bubble argon through your molten metal, and molten aluminum and stell of any kind is a big nono. Molten aluminum dissolves steel and iron. So you need a crucible. Melt it and pretty much as soon as it is melted you pour it. The hows and whys of pouring are covered well by Martin in his last video.

Soooo, my steel crucible it not good. This means I am getting iron alloyed into my aluminum?

[mwmkravchenko]

Aluminum while molten dissolves iron. Makes for a terrible alloy. All is not lost. There are refractory paints, refractory washes that you can coat your crucible in and it protects the aluminum melt. Cans are almost pure aluminum. Absolutely nasty to machine. A little copper and silicon makes a huge difference. Look up the alloying of different aluminum. I applaud your getting it done. I haven't done any regular casting in almost 30 years. I do want to get back into it. And electric is one of the best ways to do it. Not a lot of hydrogen absorption into the molten aluminum when you melt via electric heaters. Saves the degassing with argon. Expensive and a little bit complicated.

Mark

Another great teacher is: https://www.youtube.com/@kellycoffield533

[neilbourjaily]

I doubt cast iron has much to do with this method. Molten Al is a solvent to iron.
I suspect the black is a graphite wash of a sort. Graphite is useful as a parting agent and lubricant in Al casting.

Sorry,Mwmkravchenko, I didn't see your immediately previous post.