The overall question is how to calculate the current carrying capacity of a thermal relief. IPC - D-275 indicates that the total area of the thermal ties should be used to calculate the current. However, the chart on page 10, to calculate current capacity of a line makes a assumption that this is a long free line. Since the thermal ties are very short (.010) and tied to a plane. This adds a lot of heat-sink and it looks to me like this needs to be taken into account when calculating current capacity. Any experience out there with this problem? ----------