scraping off completely defective area.
That there is no defect as required shape in welding work.
except to clean oil, water, and dust.
Part that there should not be a Zaku nest in the thick portion to remove 5mm deeper than the surface finish.
(Such as packing seal surface of the valve body example)
there should not be a Zaku nest in the thick portion is removed deeply than 5mm surface finish.