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Page4 Venturi and Needle Valve Assembly

Venturi is turned out from aluminum bar. I failed twice because the wall was very thin and was distorted in spite of careful turning.
Right two are those who were distorted. It took several hours to reach this stage.
My heart was almost stop at that instance.

the failure like this usually happen at the last stage of long and meticulous work.
I can find many examples like this in the web site.

I made mandrel and in that mandrel I turned out. The left side is successful one and next to it is mandrel.。

At this stage, I must do the soft soldering the venturi and cylinder.
I have never done it, so I practiced with bar stock again and again.
I spent two weeks of training and got some advises from the stuff of metal-carving shop.）

To set up for soldering, I used a 2mm screw and a nut.
If you look carefully, you will find the satin on the cylinder. I failed at first and had to practice.

After soldering. It took almost one month to make this one!