Hot plates in the doublebacker (DB) section must be maintained so that the leading edge of any plate is level with or slightly lower than the trailing edge of the preceding plate. The consequences of a leading edge plate that is higher than the previous plates trailing edge can be: Flutes crushed as the hot board runs into and rides over a high lead edge. This can negatively affect caliper and box compression. Disturbance of the DB glue line can occur, especially if the high leading edge is early in the hot plate section when the glue line is still in the early stages of bonding. This can cause weakened bond and delamination.