I have broken a rod as well by casting with weighted flies. A couple of years ago, I tied a few flies just for practice casting so I would not break a rod again (hopefully!).
I cut the bend off the hooks, wrapped enough wire to give the hook the proper weight, then wrapped that with closed cell foam.
Wrap enough thread around the foam to prevent it slipping off, but not so much as to remove all the "spongyness". My practice flies are now these white blobs, and I have not broken a rod since.
Hope this helps for the future.