Just a quick follow up on this. Haven't had a chance to revisit this in video form yet.
These, whilst nice and tight initially, didn't last long with PLA. Probably only a couple of weeks of presure before they relaxed into their compressed state.
A slightly oversized plastic plug and dremmel it until it fits nicely in a candiate socket was the final solution I adopted.
Too many things to work on, too little time, but these experments should be considered a null result unless you're printing in nylon or something.
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