Not to sure about breaking in molds,never had that problem ,definatly starting off with a warm to hot mold makes a big difference on appearence,you will through time find that the molds will break down and warp with excesive use ,as far as impurities ie tin ,zinc,babit,they will be next to impossible to remove with a simple melt and re-melt again process,when i run into this type of lead i use it for other things , Yeah Mike if you have to use tire weights i would use it as terminal tackle ie hali weights,they just don't seem to fish well as bigger weights for salmon ,but that won't be a problem for you ,still haven't seen you use those riggers yet,as for wire thats where i get supersitous,i use copper brass ,gives out positive currents ,if you ever look at commercial troller lead almost 90% use and have used the copper brass eyes,as you know some of the best fisherman make a point of looking after there balls!!