So when I wake up bright and shiny at birdsong o'clock and began my day, it was a bit of an effort. Wind there was aplenty, gales of it blowing off the lake, making standing down wind of the hearth a bit tricky. The chill of it made me a bit insensible to the touch of sun that I earned own my shoulders early that morning.
The bellows stone began the day in three pieces, so I shored it up with rocks and pegs to hold it through the rest of the day.
I began first thing by relighting the hearth and starting up one crucibles packing it with of 50g copper and setting the molds upside down in the second hearth and setting just a few pieces of charcoal in that hearth to try to gently warm the wax out of the mold, whether through it heating too rapidly or just the stress of contraction around an object 80% of the molds split. I think this may just be a tendency as this also happened in the very controlled kiln firings earlier in the experimental process. After all signs of the wax was gone, I began piling the charcoal on to fire the molds through,
Myself, earning my sun burn, and fussing with main hearth, while my very kind assistant (Yvette ) helped me tag off on keeping the the air flowing to begin to melt the copper.
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Working some more on my soon to be crucible tongs.
While waiting for the first crucible to get up to temp.
While working slowly up to a good heat. 1 hr at a gentle pace to get the worst of my crucibles up to temperature and then another hour at a moderate pace and then about 20 minutes at what we could best describe as a gorilla running the bellows' pace'. In the end we were able to melt the copper (apx 2000'f ) and then add the alloy and then I poured it off into water as casting grain to get a good look at what we had made, since the molds weren't yet ready. It had good flow and colour and on the few stingy bits a fair bit of ductility.
Fiddling around with it, checking on the crucible, the hairline crack that had begun to open up, the fluxing on the outsides, it's contents and generally learning more about charcoal fires.
The first successful pour was just slightly after this picture and then we took a break for lunch after piling some more charcoal on the mold hearth.
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After lunch I inspected the now glazed and abused crucible and it's top and made the call that the next two would go in but should probably be turned every time we changed bellows operators, every 15 minutes or shovel full of charcoal apx. That way the damage and stress of the blast side of the hearth could be mitigated.
In the crucible, closest to the bellows I put the freshly alloyed copper alloyed with 10% lead free pewter (rio grande) and in the second I packed another 50 g of copper.
At a full 1 bellows per second speed (about) this sort of fire can be achieved, hem and only slight scorching of the cabinet occurred :)
My first, start to finish viking cast ever, immortalized, way too hot glove, hitting the guyline, cursing, and all :)
Petov, another of my excellent bellows volunteers, also of note are the lady AJ and Jobjorn (sp) who each spelled in for a while as their days allowed. many others helped through the days by bringing me food and water, and taking pictures and video and generally keeping company with us and helping talk to the curious when I was too focused to do that good work.
It looks a right mess but this is a day well done, with the ashes scattered, crucibles cooling and my worker bees and myself just chilling on the lawn and wondering about dinner and massages.
My wee little Upsalla birds! Both have significant but clear and obvious problems.
1- both of them had charcoal bits and or ash fall to the lowest part of the mold. Tamping gently upside down just prior to casting and or adding a relief spot for this should solve the problem.
2- neither of the molds and or the metal was hot enough to give sharp detail. I think the molds were too cold, but being quicker on the pour by being able to be on the right side of the forge (baring inconvenient winds again) should in combination, make for a very nice, crisp well filled mold.
This above is the first crucible I alloyed in. It was the only one that had a hairline fracture and I wanted to
know how it would hold up, the answer is, surprisingly well, it's not in great shape, but it did the job.
The other two faired better, in part because we knew at what colour of heat things would be melting and I also think that the turning helped distribute the abuse. I am interested to see if these external cracks continue to develop or if they will stabilize at some point. Others who have done this sort of casting have said that they can get about 10 firings from stoneware molds, time will tell.
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A sad end to a cute bellows stone, much more grog next time, but really I'll try some soap stone if I can get my hands on it reasonably. I'll need about 20-25 cam square and about 3-5 com thick
Some very crude glass/ fluxy material was attached to two stones that were just below the outlet pipe of the bellows.
The end...... of the day, but not of the adventures. Bigger better and more to come.
Orla
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