If you look carefuly at pictures of paddlers in UK you will notice very few rivets showing as they were mostly flush riveted. On ships that come alongside piers etc frequently, any domed rivets could possibly catch on protrusions and diplace domed rivet heads. I think this was discovered on TITANIC on its slide along the iceberg! I have seen a lot of rivets on models and they are almost all oversize - scaling out about the size of a melon. (tug builders and some hull manufacturers seem prone to rhis). Rerds, Walter.