Friday, June 12, 2015

Just enough time to burn one before work....

I woke up around 7AM this morning, waaaay before my alarm was set to go off. But my mind was already racing thinking about the day ahead.  It was still 2 to 3 hours before I had to be at work so I decided to see if I could get some molds made up and a pour done in that time.

There are still two patterns I want to cast before I'll consider this initial adventure in casting a success. One is the Jar key chain patterns that I'm determined to make work.  The other, of course, is the bear. But fuck that bear, I don't feel like dealing with him this early in the morning! So jar it is. (Start time 7:15 AM)

Got the patterns in the drag and the parting line established. I used a liberal amount of parting dust this time. Forgot pictures prior to this since the coffee hadn't kicked in and this is heroically early in the morning for me. (7:37 AM)

I used brand new Petrobond and ran it through the riddle (a.k.a. strainter) for about the first inch of sand in the cope that would contact the pattern. I did this on the side facing the drag as well. This was to ensure good contact with clean Petrobond to the pattern. The remaining space in the flask was filled with previously used Petrobond. (7:41 AM)

The flasks separated fairly evenly though I'm still getting some overlap sticking near the edges. I need to figure out why that's happening but it doesn't seem to be a deal breaker for this mold. (8:03 AM)

The gates and runners have been dug and I successfully drawn the patterns from the mold. Note the judicious use of powder, that and fresh, sifted Petrobond seems to be the key. (8:14 AM, I really need to get faster at this!)

The furnace has been going for a few minutes already and I'm preheating the aluminum from my previous failures... I mean learning experiences... which I'll be using for this pour.(8:24 AM)

The aluminum is melted and appears to be up to a good temp for pouring (1350.7 °F). (8:43 AM)

Poured the aluminum and smoked... smoked... smoked.... For future reference, the aluminum could've been just a bit hotter but it poured decent enough. (8:48 AM)

Then, jump in the shower and get ready for work (don't worry, no pics of this)... while it cools enough to bust open.

And, here you go!! (9:20 AM)

I'm very pleased with the way it came out! I still need to clean them up a bit on the sander and maybe a spit polish, but overall I'll call this a success! I'll post more pics once that's done.

So the total time to do this was a bit over two and a half hours including set up and clean up. It is a little too much work just for one flask worth of aluminum but it was cool to know I could squeeze one off before work.

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