Another successful switch replacement here! I had sent my Chuck back to Jeff a few months ago for a switch replacement, as it wasn't firing consistently at all. About a week ago, the same mis-fires appeared. So I decided to replace it myself, using the Radio Shack switch mentioned here. I was quite surprised to find, when I removed the old switch, which had just been replaced by Jeff, it seems to be the same as the .5A RS switch I just purchased at Radio Shack. I thought the switch supplied in the Chuck was a better grade 3 amp switch? In any case, no big deal.....it fires consistently now, and replacement was fairly easy. I just need to grow a few more hands for the next replacement.