Polish the cut off area of the sand, insert it into the water, there should be no air bubbles, then wipe and apply the flux.
砂皮打光截斷處，插入水中，應沒有氣泡，然后揩干并涂上助焊劑。

Solder (or gas)
用焊錫(或氣焊）

Seal the process port of the compressor, which can be welded into a tin ball to avoid leakage.
封住壓縮機的工藝口，可焊成錫球狀，以免滲漏。

③ The process mouth of the compressor should be sealed and then immersed in water, there should be no bubbles.
③將封住壓縮機的工藝口處再浸人水中，應沒有氣泡。

And then you take this part of the liquid copper tube that's sealed,
然后將封好口的這段加液銅管，

Use the cone handle to make the core wound into a spring shape.
用錐柄做芯繞成彈簧狀即可。