bi frustum conical shape fig4 and 5 show the bi frustum panel spacer being used between two panels such as in a paneled door joint as seen the preferred shape of the bi frustum panel spacer has two identically sized conical frustums joined together end to end at the larger of the two ends the comparative dimensions of the preferred bi frustum spacer are such that the minor diameters at the terminal ends of the spacer are a shorter length than the axial length of either of the frustums and the major diameter at the large end of the frustums is also shorter in length than the axial length of the bi frustum panel spacer the preferred size of a bi frustum panel spacer is slightly wider than the width of the groove that the spacer will be used in so as to insure a snug fit but yet retain optimal resiliency for example a wooden panel with a one quarter inch 0 250 34 groove would accommodate a bi frustum panel spacer with a major diameter of approximately 0 265 34 and an axial length of approximately one half inch 0 500 34 the bi frustum panel spacer is preferably constructed of a resilient polymeric material such as what is known in the trade as 34 40 shore 34 natural rubber with the following specifications specific gravity 1 01 tensile strength 3 405 psi elongation 707 tear 152 ppi as are commonly used for a better understanding of the invention.