This paper presents a new method to calculate stray capacitance between conductor wire filaments. The new proposed method is called vespiary regular hexagonal (VRH) model. In this paper conductor of magneto cumulative generator (MCG) coil has a multilayer wire. So the proposed model is used to calculate stray capacitance between two adjacent wire filaments (WFs) and capacitance between the wire filaments and central cylindrical liner in one turn of coil (OTC). The presented method in this paper is based on an analytical method and geometrical structure. In one turn of coil, the wire filaments in VRH method are separated into many very small similar elementary cells. In this structure, an equilateral lozenge-shape basic cell (ELBC) with two trapezium-shape regions has been considered between two adjacent wire filaments. This method is applied to calculate the total stray capacitance of N-turns of coil (NTC) with multi WFs in round cross-section. Simulation results show that the proposed method is very useful for designing a geometrical structure of the MCG coil.