And also why it's sometimes difficult to find transverse cracks.My former job was in NDT and I used to do Mag Testing every day... Those look just fine. If you watched him do the test, he should have applied the spray twice using the electro magnet in two different angles like an X pattern. What happens is... There is a fine metal powder that rushes back and fourth from prod to prod, and will get caught up in, or gather up at a crack (short and simple explanation) and the crack (indication as we had to call it) has to be perpendicular to the prods so that the powder goes accross it (the reason for 2 applications in an X pattern) or it won't show up very well sometimes. That same powder will gather up at any rough edge (paint to bare metal, gobbed up weld, grind mark, chip in the surface, etc) and get false indications if you're not careful.