Spool Holder for Ender 3

Yet another spindle holder. Why? I have a number of old Taulman spools with only a 19mm hole, so they don't fit either the stock tube or any of the other mods to fit the stock bracket. Like so many others, I found that the friction on that stock tube introduced quite a lot of resistance to the spool's turning until a threshold was reached - then the spool would jump forward a tad. Unacceptable.
One of my pix shows the make-shift taulman hanger - an extendable dowel that worked but is too ineligant for even me. So I borrowed some ideas from other similar designs, although I did design all from scratch, ultimately.
I chose 1/4-20 SAE hardware, mainly because the local hardware store has more choices along that line. I should admit to a couple changes from what's shown for hardware: the bearings shown are a larger outer diameter than what I ended up using - but they're not included in the STLs. I also used different nuts than shown: for the outer one I used a nylocker; for the inner