Using a hammerstone for secondary thinning

For you knappers out there, I decided to post about thinning with hammerstones. I am no expert at this, but I  have gained, through experience, a basic idea of how to use a hammerstone for thinning. First, use a small hammerstone, it should be no larger than the end of a billet used for similar purposes. Secondly, abrade a lot  , make sure the platform is well rounded and dull. A relatively slow strike should be all the force required to detach a flake that will go past the center.