Movement Settings - Quick Question

Hey all,

My printer is completed and I've been doing some dry runs (waiting on filament to arrive). After speaking with a friend that has also built Prusa Mendels, he suggested if everything looks correct the only thing I should do is slow the print speed down when first starting out. Right now the X/Y seems to shake vigorously when doing infill. So my question is what should I set my movement settings to in order to slow the print down? Is this arbitrary because each machine is different? My current configuration for movement and acceleration is copied below. Thanks for your help!

Prusa Mendel
Ramps 1.4
Arduino AT Mega 2560
Pronterface

//-----------------------------------------------------------------------
//// MOVEMENT SETTINGS
//-----------------------------------------------------------------------
const int NUM_AXIS = 4; // The axis order in all axis related arrays is X, Y, Z, E
#define _MAX_FEEDRATE {350, 350, 2, 45} // (mm/sec)
#define _HOMING_FEEDRATE {1200,1200,120} // (mm/min) !!
#define _AXIS_RELATIVE_MODES {false, false, false, false}

#define MAX_STEP_FREQUENCY 30000 // Max step frequency

//For the retract (negative Extruder) move this maxiumum Limit of Feedrate is used
//The next positive Extruder move use also this Limit,
//then for the next (second after retract) move the original Maximum (_MAX_FEEDRATE) Limit is used
#define MAX_RETRACT_FEEDRATE 100 //mm/sec


//-----------------------------------------------------------------------
//// Acceleration settings
//-----------------------------------------------------------------------
// X, Y, Z, E maximum start speed for accelerated moves. E default values are good for skeinforge 40+, for older versions raise them a lot.
#define _ACCELERATION 1000 // Axis Normal acceleration mm/s^2
#define _RETRACT_ACCELERATION 2000 // Extruder Normal acceleration mm/s^2
#define _MAX_XY_JERK 20.0
#define _MAX_Z_JERK 0.4
#define _MAX_E_JERK 5.0 // (mm/sec)
//#define _MAX_START_SPEED_UNITS_PER_SECOND {25.0,25.0,0.2,10.0}
#define _MAX_ACCELERATION_UNITS_PER_SQ_SECOND {5000,5000,50,5000} // X, Y, Z and E max acceleration in mm/s^2 for printing moves or retracts

what are you using to slice ? The speed is usually set when slicing.
I see you are using pronterface, so are you using slic3r ?
You can press "slicing settings" in pronterface, and then slow the speed down when the slic3r settings open.

The speed is set in the slicer, yes, but the firmware imposes the ultimate speed limits. If the slicer is asking for a speed higher than the firmware is configured for, it will just never attain that speed. It's better to have speed settings suitable for the printer in the firmware configuration. That way regardless of the source of the file, the printer will be protected.

So do you think my firmware configuration is appropriate? I am using slic3r and right now everything is set to the default values. Is slowing down the speed just a matter of adjusting the speed settings to whatever gives me a good print? I have attached the current slic3r settings, thanks!

I'm not at a PC right now (posting from my phone)
But you want to switch slicer to "advanced"

Then you can either have fast but not as good prints, or slow but amazingly fantastic prints.

Switch slic3r to advanced, find RichRap's blog about how to set up slic3r
(google richrap) and read the WHOLE thing ;-)

The only thing that comes to mind is your movement looks slow.
I have mine at about 200.
Everything else I have slower than default. I think I have small perimeters at about 10mm/s, outers at 25, normal perimeters at 50.
Everyone is always after "fast" for some reason, but as I'm not running a factory I prefer quality.

(when you show your friends a print, they ate interested how good it looks, not how fast it printed (usually)

Oh, and read "triffid hunter"s calibration page.
The "measuring method" gets you close for extrusion, but if you want to print earrings, calibrate via the triffid hunter method afterwards.

Hope that helps.

Thanks DaveS! I am also looking for quality over speed, RichRap's calibration procedure is fantastic.

It is...

but then do the

"E steps fine tuning" on this page

[reprap.org]

that's how to *really* get it perfect.

Edited 1 time(s). Last edit at 01/07/2014 06:07PM by DaveS.

I Have Prusa Mendel and the same electronics as you. Like you, i have recently learned that all printers are quite different after calibration. I went through several speeds with terrible outcomes. I now have very good speeds that get the job done without stressing my motor drivers. This is my most recent firmware settings: Diregard the steps per unti, this is custom to your pulley wheel, belt teeth and a few other things

#define HOMING_FEEDRATE {50*60, 50*60, 4*60, 0} // set the homing speeds (mm/min)

// default settings

#define DEFAULT_AXIS_STEPS_PER_UNIT {74.5,106.91,2560,955} // steps per unit for prusa mendel x,y,z,e
#define DEFAULT_MAX_FEEDRATE {300,300,5,45} // X, Y, Z, E(mm/sec)
#define DEFAULT_MAX_ACCELERATION {2000,2000,100,5000} // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for skeinforge 40+, for older versions raise them a lot.

#define DEFAULT_ACCELERATION 3000 // X, Y, Z and E max acceleration in mm/s^2 for printing moves
#define DEFAULT_RETRACT_ACCELERATION 3000 // X, Y, Z and E max acceleration in mm/s^2 for r retracts

//
#define DEFAULT_XYJERK 30.0 // (mm/sec)
#define DEFAULT_ZJERK 4.0 // (mm/sec)
#define DEFAULT_EJERK 5.0 // (mm/sec)

Try it out and see if it works