I've done a couple CuMai blades and as long as the Copper is not on the cutting edge it shouldn't be a problem. I also did my Homework on the Copper to steel bond the shear on that bond (I looked for the article and couldn't find it) is around 70,000 PSI!! These are hand knives 1 is a hunting knife that has some defects on the blade (not selling its mine for life) and the other is a friction folder. For me to hit 70,000 psi sheer on the blade of either knife would be a feat! I really like the affect, it was something different and a challenge to me! That's what I consider a lot of this knife building to be, a "PERSONAL CHALLENGE". That's how we evolve and become better makers! In a nutshell just make what you like and challenge yourself to 1 up every knife you do! At the very least try and learn something from each build, whether your using repurposed material or known!