Large unmanned hexacopters fitted with 20-litre tanks for carrying fertiliser or pesticides follow pre-mapped routes and spray crops accordingly. This isn't a case of new tech replacing old farm ...

sprayer tank. I built the frame of the stand for a 250-gal. water crate from 1"x2" tubing and 3" angle iron. Pallet forks slide into 3"x5" tubing. I used steel sheeting for the chemical jug ...