< Cylinder Block Casting >
As usual, wood pattern for the cylinder block is cut by Modela. The cylinder block is so huge that the pattern is divided into 15 parts within Modela's capacity. Then they are glued together. I utilized chemical wood "Obomodulan" made in Germany.
It took 250 hours around the clock to cut these parts by Modela.
The photos show glued patterns. The width of the pattern is around 300mm. The core-prints are painted in various colors so as to collate with core boxes.
It is back half of the patterns. Note the locating dowels and the finger gripping holes.
Core boxes are cut by Modela, too. Only the bottom one is divided into four parts, so as to draw out the core easily.
I requested a local non-iron foundry to cast it. They did not guarantee its result because the patterns are much complicated. Finally they succeeded but I heard it was troublesome and spent many times to reach success, and also some coreboxes had to be modified. As a result, it costs double as I expected.
The photo shows view from the underneath. Unnecessary metal is perfectly removed by the cores.
I took 0.5mm plays for putting core parts together. But it was surplus. As a result, unwanted walls were left between the cores. I have to remove them before borings.
The photo shows a pair of core boxes modified by foundry staff. It shows that I should have divided them into three pieces in each. The foundry wrote "Please design corebox with cares" on the bill.
Anyway, I got the most important casting of the project!