Santa, credit BeeSource member Charlie B. for that. He's been widely imitated. I actually found an example on YouTube before I found it here. Mine are slightly different, split so they can be removed for cleaning and re-greasing. The grade of grease matters ... some formulations are too runny. Mine have EP moly grease in them because I had it on hand, but I think the word was you need a proper axel grease.
It works, except if you leave a cable or rope dangling from the platform, or blades of grass, etc., the ants take the bypass.
I'm using the same strategy on hummingbird feeders. We have some Ant Can'ts that you're supposed to put water and detergent in, but if you invert them and use grease, they don't need refilling.