It is never too late. Forget about how old you are and quit looking to the past - look to the future. You have probably heard it before, but I think a good way to look at it is that "Tomorrow is the first day of the rest of your life." Pursue what you want and what will make you happy. I know what you mean about not have the shop knowledge - I have thought about doing the same thing; however, contrary to your situation I am almost to retirement and want to pursue the same thing you do.