wires to the die body as illustrated in fig3 assembly 42 is mounted in hole 19a of panel 19 and assembly 43 in hole 18a of panel 18 with electrode wire 44 stretched therebetween spanning substantially the length of air passage 36 and generally perpendicular to the air flow therethrough assembly 43 comprises bushing 46 mounted in panel hole 18a jack member 47 abutting bushing 46 and jack cap 48 threaded to member 47 bushing 46 is made of an insulating or dielectric material such as ceramic and has a hole 49 sized to sealingly receive wire 44 one end of the electrode wire 44 is attached to the exposed end of jack cap 48 by brazing or a connector as at 51 connection 51 supports one end of a tensile load in wire 44 induced by assemblies 42 and 43 as described below the tension is transmitted through the threaded connection between jack cap 48 and retainer 47 and compresses the retainer against bushing 46 wire 44 extends through the mounting assembly 43 through panel hole 18a and into air passage 36 assembly 42 retains the opposite end of wire 44 and compresses a bushing 52 comprised of a ceramic or dielectric material spring 53 and retainer 54 bushing.