muele-marlin/Marlin/example_configurations/delta/kossel_xl
AnHardt 7188ce0ad6 double bump probing as a feature
Why double touch probing is not a good thing.

It's widely believed we can get better __probing__ results when using a double touch when probing.

Let's compare to double touch __homing__.
Or better let's begin with single touch __homing__.
We home to find out out position, so our position is unknown.
To find the endstop we have to move into the direction of the endstop.
The maximum way we have to move is a bit longer than the axis length.
When we arrive at the endstop - when it triggers, the stepper pulses are stopped immediately.
It's a sudden stop. No smooth deacceleration is possible.
Depending on the speed and the moving mass we lose steps here.
Only if we approached slow enough (below jerk speed?) we will not lose steps.

Moving a complete axis length, that slow, takes for ever.
To speed up homing, we now make the first approach faster, get a guess about our position,
back up a bit and make a second slower approach to get a exact result without losing steps.

What we do in double touch probing is the same. But the difference here is:
a. we already know where we are
b. if the first approach is to fast we will lose steps here to.
But this time there is no second approach to set the position to 0. We are measuring only.
The lost steps are permanent until we home the next time.

So if you experienced permanently rising values in M48 you now know why. (Too fast, suddenly stopped, first approach)

What can we do to improve probing?
We can use the information about our current position.
We can make a really fast, but deaccelerated, move to a place we know it is a bit before the trigger point.
And then move the rest of the way really slow.
2016-07-30 03:00:49 +02:00
..
Configuration.h double bump probing as a feature 2016-07-30 03:00:49 +02:00
Configuration_adv.h Unify config in a single include without nested includes 2016-07-25 23:04:19 -07:00
README.md Updated Kossel XL config files for the latest Marlin 2016-04-17 20:04:19 -07:00

Configuration for Kossel k800 XL

This example configuration is for a Kossel XL with a printable bed diameter of 280mm and a height of 380mm. It also has the auto bed leveling probe (with an endstop switch) and the heated bed activated.

Configuration

You might need (or want) to edit at least the following settings in Configuration.h:

  • MANUAL_Z_HOME_POS - The available height of your printing space. Auto Bed Leveling makes it less important to have the exact value.
  • DELTA_PRINTABLE_RADIUS - The printable radius is how far from the center the nozzle can reach.
  • DEFAULT_AXIS_STEPS_PER_UNIT - Steps-per-millimeter for the delta steppers, and for the extruder to optimize the amount of filament flow.

Fine tuning

  • Increase DELTA_RADIUS if the model comes out convex (with a bulge in the middle)
  • Increase DELTA_DIAGONAL_ROD if the model comes out larger than expected

[http://reprap.org/wiki/PID_Tuning](PID Tuning)

  • DEFAULT_Kp - The proportional term
  • DEFAULT_Ki - The integral term
  • DEFAULT_Kd - The derivative term

PSU Options

  • The power supply is configured to 2 (to use a relay to switch 12V on and off)
  • It is configured to be off by default