
I tried 3/16" "- and 1/4" steel mounts. Just a few holes, the drill bit is totally useless. It's a huge piece of metal and costs almost $20, but when the tip dulls after a few holes, it's pretty useless.I understand that the task of drilling is difficult but I think they should post information on how long the lifespan (by type of different materials) can be expected from this tool.