You don't want to cut posters on the Graphtec for a couple reasons. The least important problem is simply the blade and cut strip are going to deteriorate super fast. The most important problem is, when the posters get cut out and fall off, the paper will lose stability, crumple up and jam the machine. You can fix the problem by using the perf cut feature but the edges will be rough and have little chads hanging off. You can also laminate some transfer tape to the back of the paper to stabilize it but that is way too much work and extra cost to justify. At the end of the day it's just not something the machine was intended to do. Is it possible? Yes. Is it worth the trouble? That's up to you. You should look into a javelin cutter. It has to be manually operated but it does cut time off from using the xacto and ruler.