I made cylinder blocks. A 30X30 brass square rod was cut to the length.

シリンダーブロックを作る。まずは30X30の真鍮角棒を必要な長さに切断。

Also 20X20 was cut as valve chest material. Their ends were cleaned by lathe.

同様に20X20の真鍮角材から弁室材料を切り出し、端面の旋盤で綺麗にしておく。

Above materials were roughly cut to required thickness.

上記材料を更におおかかに切断。

Cut out materials. Arrow parts were waste.

切り出し完了した材料。矢印は切り取った不要部分。

Centre of cylinder hole was marked by centre drill after positioned by edge finder and DRO.

シリンダー穴の中心をセンター・ファインダーとDROで出し、センター・ドリル。

It moved to the lathe and drilled with 10mm drill.

旋盤に移し、10mmドリルでシリンダー穴を開ける。

The hole was enlarged to 11.8mm by boring. Accuracy of drilling is not expected and it should be bored.

中ぐりであな径を11.8mmくらいまで拡大。ドリル穴の精度は期待できないのでいきなり11.9mmとかのドリルで開けず中ぐりすべきである。

It was finished with 12mm reamer.

12mmのリーマーで穴を仕上げる。

The end of the cylinder block was finished to keep right angle against the hole.

シリンダー・ブロックの端面を仕上げ切削。これで穴と端面の直角は確保される。