If your doing lead came work, then sooner or later you’ll need a lead vice. Sprung loaded, for ease of use. With reverse teeth to grip the lead prior to stretching. Feed one end into the vice and then pull the other end with some wide nosed pliers and gently strecth the lead.
Lead came must be stretched prior to use. Not only will this remove all kinks but also offers more strength.
Fixes easily to a workbench or other sturdy point.