This one took me a bit longer expected: My guide on understanding how your printer moves and how to tune your its speed settings for maximum reliability.
http://www.youtube.com/watch?v=7HsIZuj9vOs
http://www.youtube.com/watch?v=7HsIZuj9vOs&t=2m13s - I now have a sound clip of @Thomas_Sanladerer saying “Jerking off”
@ThantiK knew you’d enjoy that one 
Great stuff! I imagine some of the recommendations you make are controversial and I hope they spark some conversation. I also look forward to getting my bot printing again and doing some testing. Thanks!
@John_Davis I’m sure they are controversial! None of the instructions i give are set in stone and universally true, they are simply the way that gets stuff done in my experience.
Is the resonance a function of the bearing contacting the rail, or is it the motor resonating with missed steps or even half steps? Or something different all together?
@Andrew_Radovich_BadW resonance is a function of the tension on/springiness of the belt (mostly). You can’t tension it so tight that it bends your rods/motor shaft and the rubber has some play in it.
Ah. Thanks Anthony
@ThantiK I wanna know who REALLY said F12000.
And is that an ingentis off to stage left?
@Andrew_Radovich_BadW the steppers are also quite springy and are probably a big part of the problem.
@Mike_Miller I had to splice that part in, as the original audio said F1800 (which is definitely not what 200*60 works out to).
The printer on the edge of the frame is the #Cerbris that’s (very) slowing coming together.
The X acceleration is OVER 9000!! :o
But really, this video was very helpful to me. I have been turning down acceleration settings to try to get rid of the ringing I have at sharp corners for a while, to no avail. Jerk settings, here I come.