I watched a mainland Cantonese program explaining 「打斧頭」. Since an axe is only sharp on one side. The back part of the axe is often cast with inferior materials to reduce costs. Therefore, the meaning of「打斧頭」 is "to cut corners"(偷工减料)
Does anyone think it is correct? I ask this because the allusions to 「打斧頭」 that I know are quite different.