Victor joins the Flaming Lotus Girls: Green Sand Casting

Things have been pretty much the same for the last couple of days - cut bark shapes, roll bark shapes, hammer bark shapes, weld bark shapes...
But yesterday I saw some items on a bench that I recognised - a cope and drag for green sand casting.

Cope and Drag

Green Sand Casting is something I've read about but have not yet experimented with so I was pretty excited to find out that FLG have a casting division as well. I went over and had a chat with the guy messing with the boxes on the tables. He was a chap by the name of Mark. He invited me to help him out with his casting experiment. Mark had just got these boxes made up. They are larger than any he'd previously used so he was going to do a test run.

He had settled on a toilet lid from which to cast. Apparently his teenage daughters keep breaking his!
Mark started by placing the toilet lid (or pattern) in the base of the drag and covering it with sand.

Pattern in base of drag

The sand used to fill the drag is called green sand it's a mix of silica sand, clay and vegetable oil which makes the sand stick together and take the shape of any pattern that is pushed into it.
We filled the drag and tamped the sand down into the drag.

Tamping in the sand

When it was filled to the top we placed a board on the top and turned it over. Another board acts as a base plate and both sides are removable. Since this was Mark's first try with these tools, we ran out of enough sand to fill the cope. So Mark decided to go for an open cast instead. We moved the drag to a suitable casting location and levelled it as best we could. Then Mark drilled some screws into the pattern and jiggled it out to leave the void of a toilet seat lid.

Rapping the pattern

Simple open faced mould

With the mould prepared Mark lit the furnace.

Mark lights the furnace

The furnace seems to be made out of an old gas bottle lined with fire bricks. It has a blower fan that has a propane gas feed just downstream. When the fan is on the propane/oxygen mix hits the inside of the furnace where it ignites and heats the crucible.