Monday, November 16, 2009
Not exactly what I was hoping for. I did something wrong, obviously. Or many things wrong, perhaps. I was aiming for something more like this:
This is what I think happened:
1) Casting flask temperature was too cool. 900ºf was not hot enough for this particular alloy. After a long chat with Jeff Hoover at Hoover and Strong today, I now realize that I need to increase the flask temperature to 1150º.
2) Sprue was too large and long. Slightly shorter sprue, smaller diameter.
3) Sprue location was wrong. I'm not quite sure how to sprue towards the setting though. I'll have to experiment. Perhaps not in gold, though. :-|
4) I did try to do two casting last night, with my lovely assistant, who was instrumental in drying my tears after the second try didn't turn out:
The first one was even less successful than the second, if you can believe it. This was due to my premature, over-eager metal pour. Seriously felt stupid on this one, when the metal just plugged up the hole because it wasn't even properly liquid. Silly. Mental note, count to 2 mississippi after the metal has reached liquidus. Also heat the beejesus out of the crucible before adding metal. Think red hot. HOT!
4) Take more care with wax carving. I'm fairly new to the wax carving scene and I totally used the wrong kind of wax on my first carving (see above). It was too sticky and hard to work with. The second carving was much, much better, but was lost in the first disastrous casting attempt.
I was so disappointed last night that not even a Hagen Daaz bar and two episodes of Battle Star Galactica could ease my anguish. But at least nothing exploded. (Besides my head, that is.)