and 39 the cable pair 34 is engaged in cable guides 34a and 34b best seen in fig2 and 5 of the drawings having a curved upstanding end cable engagement portion 34a 39 and 34b 39 and a apertured base portion 34a 34 and 34b 34 that holds and separates the cable pair into cable lugs 36 as hereinbefore described each welding tip assembly has a welding tip 40 a guide sleeve 41 and an assembly nut 42 with plastic insulators 43 and a threaded tip holder 44 that receives the respective tip bolts 38 and 39 best seen in fig4 of the drawings the tip bolts 38 and 39 have plated spacers 45 and washer 46 engaged on the respective cable lugs 35 and 36 best seen in fig2 of the drawings referring back now to fig3 and 4 of the drawings springs 47 and 48 are positioned over the respective tip bolts 38 and 39 extending through apertures 49 in the top 31 of the tip arm 17 a cylinder mounting plate 50 having spring receiving pockets 51 and 52 therein is secured to the top 31 of the arm 17 by multiple fasteners f a pneumatic piston and cylinder assembly 53 extends from the cylinder mounting plate 50 having typical fluid inlet and outlet lines 54 and 55 which are connected to a source of fluid under pressure not shown as will be well understood by those skilled in the art a piston rod 56 of the piston and cylinder assembly 53 extends outwardly therefrom and has a surface engagement assembly 57 secured thereto the surface engagement assembly 57 has a pair of longitudinally spaced upstanding.