My bronze Panzer tank story continues. I had much success, but sadly a failure, too. If you want to sympathize with me, read on …
When I posted my last update I mentioned that I had decided to cast directly from the polystyrene plastic model to reduce cost. This means that I will get better detail than I could otherwise achieve with a wax mould, but I wouldn’t be able to reproduce additional copies of the work in wax. So, I completed the model that I was working on. See the following pictures.
Because the tank was too big to cast as a whole, it had to be cast in pieces. I had thought to cast the top half parts together and then the bottom half parts together, but then I realized that this was not efficient. It would be better to assemble the top to the bottom first, and then cast the assembled front of the tank as one unit followed by the assembled back of the tank. The following pictures show this change.
The first casting was a resounding success! The polystyrene plastic burned out completely and I had a excellent cast. The detail was outstanding.
And then I tried to cast the back half of the tank. This is where I had the failure. At casting time I was unable to get a proper vacuum seal on the flask when I was ready to pour metal. Without the vacuum the bronze did not fully fill the pattern and I had a failed cast.
The work is now trash. I can’t complete the tank. With lost wax casting, once the original pattern is burned out it cannot be replaced.
On the positive side, this showed a problem with my casting setup when using my large 5×7 inch flask. I didn’t have a proper gasket large enough to effectively seal the flask to my vacuum unit. The gasket I was using was the gasket for the smaller flask reducing flanges and this provided only a very narrow seal on my large flask. I have since bought a new, larger sealing gasket that will hopefully prevent this problem from occurring in the future.
So, what does one do with half a tank? I recently had the brilliant idea to use what I have as an art piece. I can show the front half of the tank coming out of a stone wall! This will certainly be different and unique. It is true that out of failure comes inspiration. See my sketch setup below.
Stay tuned for my next update where I will show the final work. This will be complete with my Girls und Panzer. By that time, I should have come up with a name for this sculpture of a tank coming out of stone!