Right, mmF stood for µµF. Those 220 000 µF / 40 V caps were quite useful for experiments… 
“Experiments” huh? I remember a 200V (maybe 6 millifarads) capacitor charged up to 200V, and crowbarring it with a TO-92 (in other words it was small) SCR. Triggered the SCR via some wires which were at least 10 feet long; wore goggles. Do you want to guess which component won?
Keep in mind that one of my prior posts was about putting KiCad projects onto a Thumb Drive. As far as I remember, way before lunch yesterday, fully defined symbols/footprints/3DModels all in project folders is required.
I will not pretend to fully understand all workflows, particularly if a team is working on the design instead of just me. But I do put component values into schematic diagrams.
I insert the value when I place the resistor or capacitor (for example). But at least for the way I use KiCad, I do not see the advantage of having 100s of E96 0603 thick film resistor symbols representing the full suite of values. Or even a unique symbol for the much more limited collection that is in my lab stock. Perhaps there is some reason why it makes sense to have all of those symbols with values when collaborating on the design.
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Most components I create are based on other ones or just symbols for ICs that are not available or not organised the way I like them.
I designed a symbol for a pogopin once, inspired by another source, with the intention to use in my changes to the “openfixture” project (https://github.com/mdeweerd/openfixture ) where I added a generator of a Testboard schematic and PCB board by converting the test pins in the original functional circuit to pogopins in the test schematic and prepopulated test board.
The above is available as testlib.* .
I even generated the 3D symbols for the pogo pins based on the technical documentation.
A bit off topic, but in my machine shop, I have the standard metric drills PLUS three sets of inch sizes - numbers, letters, and fractional…and a lovely chart that shows all of them together. Why? Because some of those “drill 23”-type thingies fit in between the standard metric 1/10 mm steps. So OK to knock it until it saves your bacon in a mechanical prototyping project 
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My favorite hole-size charts for fasteners are the drill-tap charts from LittleMachineShop. Two charts (one pdf), one for “American” screw sizes and one for metric screw sizes. These charts give tapping drill sizes for both 75% and 50% threads, as well as clearance drills for both close fit and standard fit. Unfortunately the “American” screw size chart doesn’t give metric equivalents, but the metric chart does give “Closest American Drill” sizes for all columns.
I’m not a machinist so I don’t know the accuracy, but I trust the source and the few holes that I’ve drilled (or specified on a PCB, or 3D printed) and tapped based on that chart have worked perfectly.
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