I've not tried using a juicer for fresh root juice making...one thing to keep in mind is that if you run fresh root / stump through a juicer* you will end up with--
1. --pure juice (like carrot only kava) and 2. -- pulp...you'll totally need to take that pulp and lomi, strain through nut butter bag or something similar to full utilze the fresh root/stump.
* assuming it will not just clog up, and over heat the juicer.