There could be several things to look at but 30 min. in a day is quite a bit, I would look at a longer suspension spring or if you have room lengthen the rod, you could possibly go with a thinner suspension spring. Another thing to look at is the oscillation or arch of the pendulum, is it short? could be there is not enough lock on the pallet faces and the escape wheel teeth are missing the locking surface and hitting the impulse area of the anchor (I would look at the escapement first)….really hard to say without it in hand.
