First print, tuning advice.

Hi, I've attached a picture of my first ever print attempt. It's an i3 with a bulldog extruder and hex hot end running ramps and Marlin. It's PLA printed at 200c and 185c for the head (more on that later)
Nozzle is 0.4mm

First print was through Pronterface, although I used the model you get with Cura of a small robot. I'm printing a 2cm cube now.

[EDIT]
Second print of Cube has completed. It's 2cm in the x and y, but 14mm tall, so 70pc of its expected height.

I've also just confirmed that using Pronterface, using Z axis up 10 button goes up exactly 10mm.

[END EDIT]

First thing to note is it's about 75% as tall as it should be.

This is interesting as my DEFAULT_AXIS_STEPS_PER_UNIT in configuration.h is 2000 for Z, half what others have used. I had to use this value to make a 1cm up command go up 1cm in pronterface. So after my cube I'm going to try changing that.

Temperature of hotend is currently 200. Pronterface keeps using that temp for some reason. I'm changing the temp about half way through my cube back to 185.

What I'm not sure about is what to change to get the walls less liney and more detailed.

Any advice welcome, I can extract values from my configs if requested.

Thanks
Ian

Edited 1 time(s). Last edit at 08/17/2014 12:54PM by UkIan.

What were you trrying to print?

Also to check if your steps per mm are about correct you can use prusa's calculator.

That was the Ultimaker robot model you get with Cura. Here's a shot of the 2cm cube.



As you can see it's a bit short and generally raggardy.

What's interesting is I have the Z stepping at 8 microsteps, so my Z setting of 2000 seems accurate. Also, using Pronterface, pressing the Z +10 button raises my Z axis exactly 10mm. But something is obviously amiss as, at the top of the cube I wasn't trailing 6mm of goo across the surface (There being a 6mm gap between where the top of the cube should be and where it actually was).

What is your z acceleration? Perhaps it's too high.

These are the settings I have currently, I've actually just tweaked them down, so waiting on a print...

#define HOMING_FEEDRATE {50*60, 50*60, 100, 0}  // set the homing speeds (mm/min)

#define DEFAULT_AXIS_STEPS_PER_UNIT   {80,80,4000,107}  
#define DEFAULT_MAX_FEEDRATE          {500, 500, 2, 45}
#define DEFAULT_MAX_ACCELERATION      {450,450,100,10000}    

#define DEFAULT_ACCELERATION          450   
#define DEFAULT_RETRACT_ACCELERATION  450  

#define DEFAULT_XYJERK                10.0    // (mm/sec)
#define DEFAULT_ZJERK                 0.0     // (mm/sec)
#define DEFAULT_EJERK                 5.0    // (mm/sec)

Actually, I might have to kill that print, it's going soooo slow now. And my hot end has sprung a leak. Argh