godan verb (-su)
Rare term meaning to make something again, often from scratch or with significant changes. More common alternatives are 作り直す or 作り変える.
失敗したので、模型を作り返すことにした。
Since I failed, I decided to remake the model.
Compound of 作る (make) and 返す (return, repeat), literally 'make again'. The exact historical derivation is uncertain, but the meaning is transparent from its components.