corrosion on tin-plate

After dissembling the 259E engine completely, I stripped the paint by immersing the parts in boiling soap water for 30 minutes. The black paint just fell off by stirring the hot liquid along the items. Although there was little corrosion visible from the train in the original state, it is very obvious after stripping. Here on the photo you see the roof part of the cab and many fine brown lines are visible. These crooked rust lines that start at defects in the tin plating and form pin-hole defects. The ironoxide (rust) formed under the tin coating pushes the coating upwards, forms more defects and the rusting starts to walk over the surface forming webs of crooked lines. Much like moles digging tunnels just beneath the surface of a meadow. Nice to see and beautiful for metal-chemists, but a danger for my toy train. So, I will bring out the brass brush and sanding paper to get rid off these corrosion lines and then prime the lot with corrosion retarding paint.