Dale,
I just tried to make my first jar opener (I've got to do 20) and I had a real problem getting the large post to go into the hole after I finished it. I had to drill deeper and the only way I could get it up high enough to line up with the hole was to have the spur on my brad point bit poke through the top. I used a pen blank and left as much as I could in the middle but it didn't seem to be enough.
Did you have any trouble getting the hardware put together? Did you drill the holes after you turned it?