Casting bronze in Mexico.. unsuccessfully this time

Attempting again to cast “Haven” in Puerto Vallarta.  Last time there was a serious problem with pitting and problems around the head.  Suspect related to gases, heat and contaminants, but Hector ordered a magic powder from Guadalajara that was to alleviate or mitigate the problem (skeptical) and they were to use a different gating system, allowing for venting from the bottom up.  When I saw this sprued wax I didn’t even know what was happening…  tiny pour cup (“no problem”) and too small gates coming from it (“no problem”) and not sure what was going on around the head and shoulder — although they did attach some vents from this area at the end….

here is the “burn out oven” — I am seeing some problems already…

uh oh.  plaster obviously did not set up long enough and cracking and… look at that tiny pour cup …. and you can’t see it but the core looked not right hrough the hole.  And upon questioning, turns out that the burn out did not take place with the pour cup at the bottom!!  “No problem” — that big gate off the head?  that was where wax exited!?  and it burned out the top too, I was told ?!  really?  and how is the bronze not going to exit out the same hole at the bottom?  A plaster cork had been inserted.  Oh.  Too late.. let’s go…

Wrapped and sand secured.  The pink things are the plates that cover the bottom of the sculpture.  Nice finishing touch.  Better than our Bondo….

Meanwhile, time to melt some bronze… well, a lot of copper and some other stuff….

Copper and other stuff melting ….

That is some hot bronze… very clear with floaty stuff… I was the scraper during the pour….

ayiyiyi…  I was re-thinking my decision to wear my lime green Crocs…

It’s show time!  All seemed to go well but….

… the top of the head didn’t fill, the globe she is holding didn’t fill — the core had slipped substantially, leaving no space for bronze at the bottom (the head) and same problem at the globe.  The top of the pour (the bottom of the sculpture) was very thick and heavy due to the large void left for the bronze when the core slipped.  Too heavy — with this technique needs serious core rods to keep core in place….

Luis worked for hours welding, etc. to try to fix it, but, of course, it could not be salvaged.  This is a start up foundry and I may be willing to continue to cast small pieces there as they basically turn out fine but not going through this exercise again with big, smooth pieces  — took the mold north and casting in Oregon, with ceramic shell and controlled conditions.

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