make one with a lead fishing weight. set you container on the scale that you weigh in and put the weight where it balances on zero, wal la, tare feature.lol,i use an old ohaus triple beam that was swiped from a high school about 40 years ago,it has a long long history of weighing out bags of mexi....never runs out of batteries,always calibrates correctly,i only wish it had a tare feature...