Jerky Movement in X, Y & Z

[coreformula 0]

I have moved from slic3r to Cura as my main slicing/gcode software and have noticed a considerable amount of jerk in x,y & z movement. My print and movement speeds are 50&60 and I have a bit of custom code in the "start"/"end". Other than that everything is around the default settings. The movement is so strong that over time it is dislodging parts on the printer.

Any suggestions?

 

[Daid 297]

Printer?

3D Model?

USB or SD printing?

 

[coreformula 0]

Printer= Custom Mandel w/ Ramps 1.4 board that we have been using for about 18months w/ Slic3r 1.06

3d model= It has happened with all of them that I have attempted to print so far. Most have been test pieces for calibration

We are currently printing from an SD card

 

[Daid 297]

Have you lowered the acceleration in firmware?

Jerky movement has little to do with Cura, and more with firmware, as that handles the acceleration.

 

[gr5 1,345]

What firmware are you using? Marlin? Marlin has both acceleration settings and "jerk" settings so you might want to lower both.

I'm going to guess you are printing things made with scanning or sculpting software which gives you millions of tiny line segments/polygons and that Cura's limiting resolution is a little bit finer than slic3rs resulting in many more tiny movements that Slic3r discarded but Cura hangs onto.

I'm going to guess if you printed something low poly like a mechanical part you won't get these jerky motions.

 

[gr5 1,345]

Just in case we weren't clear - lower both jerk and acceleration by half or more and see what happens. This will be much gentler on your printer and won't slow down low-poly prints much (but will slow down high poly prints quite a bit).

Another solution is to reduce the polygon count:

http://www.shapeways.com/tutorials/polygon_reduction_with_meshlab

 

 

[coreformula 0]

I went into the firmware and lowered the acceleration and jerk by half as sugested. This got me into the range where I can tweak it at a later moment in time and the bot is not shaking apart.

Thanks for the help.