So I just bought a dollar store Ja-Ru yoyo, the “Metal Tech SpinPro” and I wanted to see what I could do with it. So I brought it home, found it had an actual bearing, axle and weird plastic response things and the capability for an actual size C bearing so I decided to actually make it a real yoyo. I put in a flat YYF unresponsive bearing and some new Kitty String and gave it a couple throws. The surprises started to roll in. It actually became totally unresponsive, it could sleep for about 15 seconds, could grind well, and was surprisingly smooth. Though I was happy with the initial results I decided that I could push it farther. It only weighs about 20 grams so it needs some extra heft. This is where I turn to you guys. How should I make it heavier. I was thinking of melting some lead fishing weights and spreading it on the inside rim but I don’t know if that would release any toxic fumes. Any advice, modders?