Not having seen the break though I do seem to think that 1/8" Brass rod is a little on the thin side because in those diameters Brass rigidity is rather feeble. If it has to be that thin Stainless steel has far more rigidity and strength. What ever metal you choose it would be advantageous to draw file the rod to provide a key to improve the Adhesive to metal grip.

The only lessons in my life I truly did learn from where the ones I paid for!