My second build was a super simple 5 minute thing. I made a weight training accessory called a "landmine."

This is just a U-Joint on the ground that holds one end of a barbell.

A U-joint has two joints mounted at 90 degrees to each other. In my case, I used the base of the striking dummy I made a couple of weeks ago to create a vertical spindle, and I used an adjustable hinge for the other (horizontal) axis. Naturally, you could use two hinges or two spindles instead.

I'm using this for a "standard" 1" diameter barbell, so the connection to the barbell is just a 1" I.D. conduit sleeved onto the piece coming out of the joint and the barbell.

For a more common 2" Olympic barbell, you would have to convert to a 2" I.D. sleeve. I didn't work up a solution for this but I imagine any kind of 2" to 1" reducer would work. The stress at the joint shouldn't be that much.