Crucible Problems

[rrnut-2]

And to think, my wife works as a metallurgy tech at a foundry with access to the spectrometers and carbon and nitrogen analyzers. Yes, I have used those perks.

Inoculation of the iron I always thought was spectacular. The foundry would turn bright white while it was being done. Once in a while we would get the fire dept called on us if it was done at night.

When you do this, make darn sure your safety gear is in good shape and that you are wearing all of it. I saw a guy on fire one day because of holes in his foundry gear when he was inoculating ductile iron!

Jim B

[DavidF]

Big Dave,
I used to take pictures of everything I did whith the casting, but now I just find myself doing the work and skipping the photos and video.
Alot of what I have been doing for people they like to keep propriatary so I dont even bother with photos as its too tempting to show them off. Most of what I have been doing lately is investment casting 3D pla printed pats, nothing fancy, just a bunch of robots and yoda heads and skulls. I do have a couple more interesting pieces im working on (that are 3d prints) but because of the expansion of the plastic and the design of the parts it is unlikely they will cast well, but I love to experiment to see what happens even though I know from previous pours they just wont come out. If they do come out, and if the design owner says its ok Ill post some pictures.
You said you didnt have any luck with casting iron? Was it a tempature problem?? Tell me a little about your furnace and maybe I can help you get er done. For now Ill leave you with a couple pics (if they will post)

[steamin10]

I'd be like a proud rooster crowing from the barn top, not hiding in some dark place. But thats me.

The furnaces I have are a twin jet McEngelvan, and a slightly smaller speedy melt, single burner. Also a 55 gallon drum furnace on LP for 'rendering' large scrap. It is frozen in an incomplete state, tho used, because of the other two furni.

It works out that the supply gas to the house is too low a pressure/volume to meet the needs of the furnace, so the supply keeps the temperature limit too low. The only way I get a high heat, is on LP from a 100lb bottle. I then have pressure problems on long run times as the bottle cannot shed enough heat at a 3rd or less reserve and ices up outside. So I had taken to warming the furnace on house natural, and then giving the hard blow to the LP fuel, for the higher temps of bronzes.
Nearly all my casting is in scrap Aluminum, as it is fast and easy. Bronze less so, because of the heat demand. If I have trouble with bronze, it is a no brainer to know why I failed with iron. Not enough BTU's generated. Someday I will get around to solving this problem, but for today I am in the middle of a massive Deck rebuild. Thanks for reading.

[Harold_V]

It works out that the supply gas to the house is too low a pressure/volume to meet the needs of the furnace, so the supply keeps the temperature limit too low.

While building the castle, a representative of the natural gas company stopped by one day, asking if I intended to have gas service. My reply to him was yes, that I would need gas for a portion of the structure (two heat pumps for the main portion), but that I would require higher pressure, as I knew that I'd build a furnace in due time. They provided me with one pound service (about four times normal pressure) without issue. That, of course, required pressure reducers for the two gas furnaces that heated the garage, lab and shop. The one pound delivery proved to be adequate to fire this tilting reverberatory furnace.

I expect that with proper design, I'd have been able to melt iron, too, but I chose to stay away from doing so in a crucible furnace.

Harold

[DavidF]

Harold, I see exactly whats wrong with your furnace...
Its just too damn pretty

[Harold_V]

Thanks, Dave. I put considerable effort in the building, as I knew that it would be VERY rewarding, and that proved to be the case. This furnace was not used for foundry work, it was used in the processing of high grade precious metal waste material, with a recovery of silver, gold, platinum and palladium.

Because there was a huge amount of flux involved, in spite of the fact that it was lined with 94% alumina, it had to be relined once. It was a fun experience, both in the building and the running.

Interestingly, the large hand wheel came from the road project in front of the castle. It appeared to have come from an old coffee grinder. It was dug up by the road crew, along with a model T jack. I had to machine away a small portion of the rim, which had been chipped. Turned out to be a perfect fit for the purpose.

Harold