Can I ask (and excuse my ignorance) why you had to use the base from another tip? Could you not have continued it on the lathe with a cut out for an O-ring? I'm not being contentious, I've never used a lathe before and I'm interested
I have never 'turned' acrylic on a lathe before
This was my first ever try working with it, that was also the reason for turning the square blanks into rods, to get a feel for cutting this type of material
I have only just got my lathe (had used OH's before for wood, but he bought me my own one) so this is my first drip tip out of acrylic and the base is not from another tip, I bought this base specifically to give myself options if I couldn't 'turn' the acrylic narrow/detailed enough to fit an o-ring
I Used to use a lathe a lot for lexan rod, It's mostly a case of keeping the tools really sharp and not letting anything get too warm - which is rarely a problem anyway on that kind of stuff if the tools are sharp... Give it some practise and you'll soon be turning out funky stuff at a rate of knots...
That first shot looked pretty snazzy, nice smooth curves and good transition from straight to curved, so fine detail is just as you say, practice, practice... O ring seatings are basically grooves so get a piece of rod you don't like the look of and just cut groove after groove, once you've done that you can use the same rod to practice putting chamfers into grooves and if you work it right you may even get some tips you like out of a practice piece which is a "Brucie Bonus"...
Ooh, and as an aside I quite like the look of that tip mounted onto the SS base, I've got the Pyrex mega from Rocketsciencemods which is built exactly the same way but i want some nice warm acrylic for winter as leaving the mod in the car will mean the drip tip will freeze the Bejeezus out of your lips ...