Steel Crucibles for Aluminum

[caintuckrifle]

I am getting tired of aluminum making pinholes through my steel crucibles! I have read of some using a ceramic wash to slow the process down but I'm unsure what to do. Can anyone help educate me on this and what I should do? I am open to any other suggestions as well Thanks!

[Nobody Special]

Simply put, molten aluminum eats steel. The first, easiest, and safest method is don't use a steel crucible. The real deal is cheap enough, although you may have to shop a bit online. (nooooo.....please don't make me look at buying metal working tools online!)  They go about 10 or 12  bucks on fleabay.

Second is use something with thick walls, watch your melting temps, and replace often. You'll still get scale inclusions in your stuff.

And I'm also guessing you didn't read the Dave Gingery books yet. Because he suggested a third method, sounds like what you're looking for, which was mixing a little fireclay and water, sloshing it around the inside, pour it out, let dry, repeat, heat slowly to bake it on. Something like that. Well worth picking up. Good read.

Do you have somebody experienced teaching you? It's worlds safer and a lot faster.

[ThomasPowers]

Yes there are compounds you can "wash" the interior of your crucible with to resist the AL eating it.  Have you researched over at backyardmetalcasting.com (now alloy avenue)?