hi ya'all i am not in technical and not a student. just wanna do a small project on my own for my small farm. ' what i want to do : 1. a lifting device to lift about 100 kg up - about 350 mm 2. then it will lower it down and the hold it in position ( need to press at this point,means exert the force of the motor here - about 190 kgf) speed of travel is about 3 to 5 seconds. after checking the net for standard parts and so on,i will be using timing belt with timing pulley. so,may i know what size of motor and gear ratio to use ? thanks all !!