Anyone know of a good place for 3D printing diagrams?

Anyone know of a good place for 3D printing diagrams? Things like the effect on perimeters on overhang, decreased layer height allowing more steep overhangs, etc?

Another good one would be a hot-end diagram, how plugs form with heat traveling too far up the barrel, or debris getting stuck in the nozzle (how to push it back up into the filament, cool the filament down, and properly pull it out)

How about icons? Anyone ever made a nice set of icons for 3D printing?

I don’t think there were any matching these specific examples, but I remember @ProtoParadigm 's blog having some good diagrams…

This would also be good for 3d printing meetups/groups and Maker Faire(s).

I don’t think any such diagrams exist yet. They definitely should though. Especially considering how international RepRap is, some handy diagrams could help bridge the language gaps here and there.