It all started because I needed a small temporary stand for one of my video projectors. Eventually, I found I could drill and tap a 5lb weight plate easily which allowed me to screw a floor flange onto it (see photo).

While the stand is perfect for that application, I wasn't too happy about the industrial look so down the rabbit hole we went.

I'll keep this short(ish):

Version 2 involved whacking the plug cut by a 1-1/8" hole saw (or was it 1-1/4"?) into the center 1" hole in another weight plate. A 1/4-20 threaded insert screwed into the wood plug and now I had a weighted base compatible with any suitably threaded (M or F) add-on (again, the photos make this clear). The wood plug is not going anywhere but a fender washer on the underside of the plate ensures it's not going to pull out.

Version 3 is (I think) the winner. Not sure if anyone has tried this before but it turns out it's possible to force a star nut into the base of a 3/4" compression connector. I squeeeezed the nut into the connector using my vise. With the star nut in the connector it can be VERY firmly attached to yet another 5lb weight plate by running a 1/4-20 screw up from the underside, again, through a 1-1/4" fender washer. It was necessary to wrap a few turns of electrical tape around the connector's threads just to keep it centered in the weight plate's slightly larger hole.

I've been using the plates primarily to hold photo lighting equipment and background paper.rolls.

I'll let the photos fill in the blanks. The coupler seen in one of the photos also has a wood plug (hole saws are your friend) and threaded inserted surgically implanted which is what allows it to be screwed onto the weight plate.