Duplo DB-250 - Appendix: Troubleshooting Guide; Spine Adjustment Troubleshooting

54
(F) Right-end nail head
LL = RL, RR = LR
You have to do the adjustment for the clamps. Slightly loosen the right-side
upper lock nuts, then gradually tighten the right upper screws of the clamps until
there is no gap between the spine and the nipping plate surface when you close
the clamps. Make some books to see if the spine has been improved on right
side.