hammer out

hammer out  {v.}

1. To write or produce by hard work.

The President sat at his desk till midnight hammering out his speech for the next day.

2. To remove, change, or work out by discussion and debate; debate and agree on (something).

Mrs. Brown and Mrs. Green have hammered out their difference of opinion.

The club members have hammered out an agreement between the two groups.

Compare: IRON OUT.