Kerosene heater works great for me. It has a “hanging” rack built-in. While I’m in the garage working on “stuff”, I hang them from the heater for about 15 mins. Then using needle nose pliers take them off the hanger and powder dip them then place them back on the heater for about 15 more mins to harden. This works great for me. I can do about 50 or so at a time.