Hi, I'm learning double bass since an year ago and I'm pulishing my bowing (french) technique these days. I think I quite grasp the concept of using the arm weight in the frog area until the middle of the bow. I get a big round sound in that area. The problem is the upper portion of the bow. I can't discover how to use the weight of the arm in that area. I tried to use more pressure from my index finger or rotating the wrist but I think I'm hurting my forearm by doing that. That pressure turns into tension and pain in the arm muscles.
How do you do it?