Rhys Ward Jones, Dan O’Sullivan, Ollie Olds and two tries from centre Gabe Brown sealed a five-star triumph. Captain Johnny Phillips added three conversions.
They will now meet Caernarfon in Cardiff next month who got past Skewen 25-12 in the other semi at Llanidloes RFC.
Iwan Llewelyn, Dafydd Thirsk and Iolo Evans scored for Caernarfon. Aled Jones kicked conversions and two penalties.
