Barbell Weight Plate

IMPORTANT: Experimental design. READ product description carefully.

This is a design that's been kicking around my harddrive for quite some time, unreleased. It obviously needs a lot of trial and error before it can be guaranteed to function properly.
For various reasons I've not yet been able to print any prototypes, meaning the design has not been tested in any practical sense.
Since I don't see myself printing this model anytime soon, I figured I might as well make it available to the public for free. Maybe some of you are interested enough to try the design, and see if it works as intended. And hopefully send some feedback to me.

How is this supposed to work?
The basic idea is pretty straightforward. The central ring goes over a 30mm or 50mm barbell sleeve, and then you screw 6 copies of the canister onto the central ring.
The canisters are hollow, and can be filled with sand or gravel to increase their weight. I suppose you could also use water, but then you'll need to seal the canisters with sealant or superglue or some suchlike.
The canisters have rounded bottoms, and when all six are added to the ring the resultant weight "plate" can be rolled on the floor like an ordinary weight plate.

Will this fit onto my printing bed?
In theory, yes. The design is modular for that very reason. Each individual component (central ring and weight canister) will fit within a 15x15x15cm printing space.

Will the threaded rim work?
I don't know.
I designed the threading based on instructions for making screw-on caps I found on the Internet. But since I've not printed the design, I don't know for certain. Worst case scenario (i.e it doesn't work at all), I suppose you could file the threads off of the canister, and then fit it to the central ring using superglue instead.

How much will the weight plate weigh when fully loaded with gravel?
I don't know. Guesstimate is upwards of 10 kg, I suppose?

Will this design hold up when loaded with gravel?
I don't know.
I tried making the design as robust as possible, but you'll definitely need to set the print density to 100 percent, or close to it.
I also don't know how well the design will hold up when the barbell and weight plate(s) are resting on the ground. The pressure might break the threaded rim. You will not be able to do super-dynamic crossfit exercises using these weights - use them carefully, and preferably in conjuction with proper plates with a diameter exceeding the 3d-printed ones.

What is the diameter of this weight plate?
Rougly 44cm with the canisters screwed on all the way. So about the same diameter as an olympic 50mm weight plate.

When you load the central ring and weight canister into your slicer software, their default scale will be about right for a 50mm barbell. But always double-check size before printing.

You need to print 6x copies of the weight canisters.

You won't need to print the parts at high printer settings, but I strongly suggest you print using as much infill as possible to maximize the strength of the design.

If you want to print the weight plate at a size suitable for a 50mm barbell, you'll need a printer space of at least 15x15x15cms.

I suggest you print the canisters standing up, to minimize the amount of supports required inside the canister. The interior walls are sloped to basically eliminate the need for supports, assuming the rounded bottom is facing the print bed floor.