ParametricPlot3D[{t(t^2-0.42)(t^2-1.85),(t^2-0.15)(t^2-1)(t^2-1.95), 10.6913t^7-.000000000000000468718t^6-30.2873t^5-.000000000000000686125t^4+22.5565t^3-.000000000000000222686t^2-7.93498t},{t,-1.5,1.5
}]

Plot3D[{x^2-y^2},{x,-40,40},{y,-40,40}]