you should measure the wire after removing the varnish and work out cross section, then attache new wire/cable of same or preferably slightly larger cross section , insulate appropriatly . (in a previous life I was a armature winder by trade)
When I initially joined it was to learn due to the absolute mess some one who was a lifetime "welder" had made on a lorry chassis I owned , so bad that although it passed plating test I sold it , total pidgeon poop.
let me know how you get on with them please , last type I used , red/black elasticated were very comfortable , easy to grip the smallest pieces but let any oil etc straight through ! so great forsay gardening but useless for spannering.