Re: Leader building
I mistyped...what I meant was the only method of using friction heat to straighten yet doesn't create too much heat to damage the material is by simply pinching the leader between your fingers and pulling it through. The reason you cannot create too much heat and friction this way is because you will feel the heat and if you pull to fast and/or pinch too hard ... you'll know it because it burns! Hence the "yelp."
When you pinch the leader in a piece of leather or rubber it's easy to squeeze too hard and pull too fast, enough to possible weaken the tippet.