We investigate the scattering phenomena at the inhomogeneous boundary of an atomic nanocontact in quasi-one dimensional magnetic structure. In particular, we study an atomic nanocontact separating two wave guide groups of semi-infinite spin ordered ferro magnetic monatomic chains. The model system is supported on a non-magnetic substrate and considered otherwise free from magnetic interactions. The spin dynamics of the quasione dimensional system is studied by the matching method, the coherent magnon transmission, magnonic conductance and the magnetic localized states are calculated and analyzed. The inter-atomic magnetic exchange is varied on the nanocontact domain to investigate the consequences of magnetic softening and hardening for the calculated properties. The numerical results show the interference effects between the incident magnons and the localized spin states on the nanocontact domain, with characteristic Fano resonances. The results yield an understanding for the relation between the coherent magnon conductance and the spin nanocontact in the perfect quasi-one dimensional ferromagnetic structure.