Wednesday, August 26, 2009

Whew!

I invested two flasks this morning; the three Ridgelines Rings and the two custom wedding band carvings. Depending on their size flasks have to dry/cure for at least an hour before the rubber base is removed and they can go into the pre-heated kiln for the burnout cycle.

I've been casting for somewhere around twenty years now, and I'm not really sure why, but I always seem to have a hard time getting myself started on a casting run. I still don't understand it. I guess it doesn't have to make sense, because once I begin investing I'm back into the groove and ready to go!

I'm suspect that some of it is the intense concentration that every step takes. Casting really is as much of an art as it is a science. There are so many different meticulous steps, from sprueing the waxes to the final quench, and so many different things can go wrong at each step . . . And yet that's also part of why I love casting! Well, that and there's just something about pouring molten metal that really appeals to me!

Since these two flasks will be cast in different metals, one in gold the other in sterling, I'll be burning them out and pouring them on different days.

The custom bands went into the kiln at 12:50 AM. I gave them an extra hour at the 300 degree Farenheit range to make sure the carving wax would have enough time to melt and drain out before the temperature was raised.

Then I gave them an extra hour at the end of the heat soak stage when I'd brought the temperature back down to 600 F. Normally for gold I'd cast with the flask at a higher temperature, but because these two rings were being cast together on the same sprue and were such different sizes my experience and double-checking some records said that 600 F would work out just right.

So rather than my standard 5 hour burnout cycle I used a customized 7 hour cycle for this flask.

I pre-heated my Electro-Melt and charged it with the gold right as the temperature was rising to 1850 F. Poured at 7:50 PM. And it was a good pour! It felt good, despite my concerns over the last couple of days about the button and having enough metal, it looked like a good button.

Then the hard part: Waiting for the flask to cool enough to quench. A good rule of thumb for karat gold is 10 to 15 minutes after the red heat has left the button. So you wait . . .

The quench went well. I can often tell if a casting worked by how a flask feels in my tongs as I quench it. This was a good one! A little lively feeling, but not too lively an action (which would mean it was still too hot). This felt just right. Roughly two ounces of gold holds it's heat in a flask filled with almost a pound of investment so I had a good quench.

They went into a glass jar and into the ultrasonic for de-vesting and I got to eat Pat's wonderful and amazing enchiladas for dinner.

And these castings are beautiful!

I don't know a single caster that hasn't admitted to me that, in their own way whatever it is, they pray when they cast. I have a good friend that burns incense on her kiln. I know folks that have their own rituals. I pray. I pray for help and guidance and a steady hand. There are just too many things that could have gone slightly wrong and ruined all of that work for me to ever, ever, be able to take a casting lightly.

Casting is a very exacting science. It's also an art where much is literally out of your hands.

So tonight I'm saying Thank You God for helping these casting turn out so beautifully!

They've been de-vested and are in the pickle in the ultrasonic cleaner right now. I'll photograph them in the morning. Then the fun part comes next . . .

Because of the technical challenge of sprueing these two rings to cast together we're going to have to use a miniature cut off disc to cut them off of the sprue. And then we'll have to re-texture where the sprues were attached before we can mount the heads and set the stones. But it'll be worth it because they turned out so well.

These rings were cast together at the same time from the same gold. And this couple will be wearing them as their wedding bands for the rest of their lives.

And that is part of what makes what we get to do so incredibly special!

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