Monthly Archives: August 2013

Pour

The big day, again. The scene at H’s foundry studio

Bronze melting in the furnace, tools waiting on the line, mold preheating in the kiln. No action pictures, sorry, too busy. (video of another pour here)

The ceramic shell molds just filled:

c_pour

As the metal cools, it shrinks, and begins to fracture the mold apart.

d_pour

After lunch, we return, anxious to roughly smash up the shell and see what we have.

Front

e_pour

Back

f_pour

What I’m looking for is; the casting is complete, no voids or freeze-out of metal in any part, a generally smooth consistency of metal and good surface details faithful to the original. There is the customary small amount of pitting or scaring caused impurities in the bronze, which gives character to the material, and nothing much in terms of flaws from/in the shell molds which would require much repair or patching, there is a nice fire scale  and color to the casting.

g_pour

h_pour

I have a tremendous feeling of satisfaction well-earned. I grateful to be working on a team with guys who can produce such things as this. I feel it is a rare thing to be working at this level of excellence in anything, and I’m glad it is happening to me.

Next day, back at my shop, I take apart the second piece more thoroughly.

i_pour

j_pour

k_pour

The shell mostly flakes away easily, and the deeper crevices are cleaned out using a chisel and hammer.

 l_pour

m_pour

n_pour

o_pour

I have two fine castings.

p_pour

Next, I cut off the sprue system.

s_pour

Now I can see the completed piece, the complete general idea. It is excellent, what I hoped for.

t_pour

Inevitably there is still much to do to detail or “chase” the casting; more cleaning, maybe sandblasting in places and patching\repairing some areas, and choosing whether or not to patina the piece and how. I’m leaning towards keeping the natural fire-scale finish, rather raw now, but it improves after a year or so naturally. Otherwise I’d considered that classic black with green haze patina we all know from museum pieces. Think about it. Another weekend and this will be ready for my show in October.

October 4 – November 1, 2013

Main Gallery: Joyce Brienza & Matt De Genaro
Opening Reception: Friday, October 4 – 7pm – 9pm

Paint Creek Center for the Arts
407 Pine Street
Rochester, MI 48307

Gallery Hours: Monday – Thursday 9am – 9pm, Friday 9am – 5pm, Saturday 10am – 4pm

v_pour

Burnout

The accretion of shell continues for 15 layers.

b_shellaccretion

d_shellaccretion

i_shellaccretionp_shellaccretion

The finished shells have their cups cut open to release the wax when it goes into the kiln.

a_burnout

b_burnout

They’re placed in the kiln, and fired up to 1500 degrees for 30 minutes to completely burn-out the wax and and any small wood pins used to support the structure sometimes. Now this is the true test to know that the shells are strong enough.

c_burnout

The wax doesn’t just melt out, it actually burns, which assures the mold is completely empty and dry, when the hot bronze is poured in later.  Any combustible material remaining in the mold during the metal pour could cause a dangerous explosion.

d_burnout

After the kiln has cooled, it is opened and the molds removed.

f_burnout

Everything looks great. No hairline cracks or flaws in the molds’ integrity. I had been worried up to this point, that the molds would be strong and sound.

g_burnout

H. and I are ready to setup for the pour next. The kiln stays nearby; we’ll preheat the shells again later when we pour metal, which is required to prevent a shock from hot metal hitting the relatively colder shell.  We move some fixtures around, and then, while digging a hole in the sand pit to place the molds into, I strain my back, which happens to me from time to time when I am not careful, unfortunately. So we must wait another week before we do the actual pour event.

What’s another week? My show’s still  six weeks off, so, why, uh, worry?