Getting Ready

So, I'm starting to get nervous. This weekend is IT! No alternative. Today I had a few more things to collect. I am very nervous about the crucible Miss. D and I worked on last weekend.I am not convinced we are on the right path with this item. I looked online to see if I could find a crucible like she has. I think she has a fused silica one. I'm not sure what that means in terms of this project, but I'm thinking about buying a crucible similar to the one at school, which I believe is a mixture of silica and clay? Anyway, I am going by Otto Frei, depsite the fact I don't know EXACTLY what I need. I know the golden rule is go prepared and know what you want, but I need some ideas! I went to Otto Frei and Larry was nice enough to help me out. I ran my project by him. Of course, I got the "Are You Crazy" look, but he gave me some good ideas. I left with a carbon stick, and a block of charcoal to use as a back-up crucible. Then it was off to the Dollar store to get some tongs. Hopefully the tongs aren't made of lead and they can handle the heat of the flask after burnout. Then over to HomeDepot for a propane torch.

I don't know if this looks like it took a lot of time to collect all this stuff or not, but it did. There are several trips to different places, and a fair amount of moola on this table. Realizing how much money and time it's taken to collect all this stuff makes me wonder how practical this process really is. However, I guess like all discovery and invention, the beginning is always the most labor and cost intensive until you get your methods and tools figured out.
When I returned home it was time to get started. I previously made a sprue button in class but for some reason I wanted to double check it. I ended up making it a little less deep and a little more flat where I would ultimately attach the sprues. This is a picture of it at the bottom of the "flask". I kept a 1/4 inch space around the edge so the investment would fill in, this way the steam has nowhere to push except down into the casting.

I decided against casting the cowboy. I made design changes to the cowboy and I decided this just wasn't the time, or the process, to cast him. I made a cheesy little heart. I discussed how I was going to sprue this with my teacher and in the end I have gone down a VERY different path than what we discussed. It seems SURFACE TENSION is a big part of this technique. Instead of using one large sprue, I am using a smaller sprue cut in half to help create some surface tension. This makes sense to me, but makes me nervous. I'm not sure if I have created enough tension and the sprue seems so small comapred to what I was going to use initally. C'mon STEAM! Show me the big bucks!

So things are looking good as far as I can tell. Seems like it's time to invest this sucker. I wrapped up the tin foil with rubberbands. Time to invest!

I followed the 2 to 1 ratio. I didn't feel too nervous about doing this. However, after I got in the thick of it, no pun intended, I wasn't sure if I got the right consistancy. There were a couple of lumps towards the end, but I didn't feel I put any in the flask. I tapped the sides to get bubbles out. Oh, did I mention I forgot to use debubbler? Oh Well! Too late now. But I did wear a mask while I mixed this stuff! Safety first!


The only problem I had was a small leak, but it didn't last long. When it was all said and done, the investment seemed to be curing and I finally had a chance to take break. I was feeling like things had gone well. Tomorrow I would cast!