Topic: Trimmer line core
As promised here is a pic of my latest core material. After hundreds of twisted cores my hands have said "enough". This is commercial nylon trimmer line. It's diameter is 3.99mm, so extremely tough. One problem is that coming off of a spool it develops a memory to curl. So, it takes a little flexing to erase most of the memory. My first prototype whip made with this core has been abused for over a year, and it still feels new. I'm confident of the integrity of this line.
First, I taper the end of the trimmer line where I will make strand drops
Then, I feed the line into a strand of paracord. It is an extremely tight fit, but with a little work it goes in. The binding isn't extravagant for this simple cow whip. I do bind several inches past the end of the line to prevent a bad hinge. The binding also helps to eliminate some of the memory curl