What the... huh???

Ummm Don't know what to say about this... This is actually probably the most complete print I have gotten off my machine yet... But have NO IDEA what could be causing it to do this...

I am thinking that the X Axis is skipping steps Maybe?

I figure I can take care of the layering issues after I get the "sliding layers" fixed... Unless someone thinkd they are related somehow...

[www.dropbox.com]

Here are my default accelerations...

Also as a side note.. the extruder stepper is VERY noisy making a sound like it's skipping steps or something...

//
// MOVEMENT SETTINGS
// @section motion
//

// default settings

#define DEFAULT_AXIS_STEPS_PER_UNIT {80,80,448,500} // default steps per unit for iPrusa
#define DEFAULT_MAX_FEEDRATE {300, 300, 300, 25} // (mm/sec)
#define DEFAULT_MAX_ACCELERATION {900,900,100,10000} // 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 acceleration in mm/s^2 for printing moves
#define DEFAULT_RETRACT_ACCELERATION 3000 // E acceleration in mm/s^2 for retracts
#define DEFAULT_TRAVEL_ACCELERATION 3000 // X, Y, Z acceleration in mm/s^2 for travel (non printing) moves

// The speed change that does not require acceleration (i.e. the software might assume it can be done instantaneously)
#define DEFAULT_XYJERK 20.0 // (mm/sec)
#define DEFAULT_ZJERK 0.4 // (mm/sec)
#define DEFAULT_EJERK 5.0 // (mm/sec)


Lots to think about I know...

Thanks for helping to bail a noob out of the mud he's in...
Don

Welcome Don!

There are quite a few things that cause shifted layers, which are documented here.
It could be any of those causes. I give up on guessing.

The default speeds and acceleration in most firmware is just wrong for most printers.

Now, I have no idea what kind of printer you have, but I will suggest some more sane settings for speed and acceleration below. Someone with your exact model can share what they use. These are the kinds of things they will need to know to help you.

Start with low print speeds and acceleration, and slowly increase them after your printer is fully working properly, changing one thing at a time until you know what that setting's limits are.

Your starting print speeds should be around 30mms, travel 70 mms. The lower print speed will give you the best chance a good prints, and the lower travel speed will help determine the cause of shifted layers. (It could be stepper current settings, or acceleration, etc).

At the start, try to keep all of your print speeds and extrusion widths the same for all types of features (perimeters, infill, etc). That means do not use auto speed in the slicer.
This will help you get printing reliably the soonest, so you can get your machine well tuned.

At the beginning you will not know how fast your hot end/extruder will be able to extrude or change pressure, so the above advice will keep you from running into the limits when you are just getting used to printing.

Start with extrusion widths 1.3x nozzle diameter, and layer height 0.4x of nozzle diameter. This will ensure that the layers are well bonded, and well within the envelope of most extruder performance. Example: a .4mm nozzle - extrusion width for all features: .52mm, layer height: .16mm to .2mm.

If you are printing PLA then be sure there is a fan blowing on the print (but not on the bottom part of the hot end).
Make sure your cold end cooling fan runs all the time. I think that about covers it.

Safer starting acceleration and maximum speeds:

#define DEFAULT_AXIS_STEPS_PER_UNIT {80,80,448,500} // default steps per unit for iPrusa
#define DEFAULT_MAX_FEEDRATE {150, 150, 150, 25} // (mm/sec)
#define DEFAULT_MAX_ACCELERATION {600,600,50,5000} // X, Y, Z, E maximum start speed for accelerated moves. 

#define DEFAULT_ACCELERATION 1200 // X, Y, Z and E acceleration in mm/s^2 for printing moves
#define DEFAULT_RETRACT_ACCELERATION 2000 // E acceleration in mm/s^2 for retracts
#define DEFAULT_TRAVEL_ACCELERATION 1200 // X, Y, Z acceleration in mm/s^2 for travel (non printing) moves

// The speed change that does not require acceleration (i.e. the software might assume it can be done instantaneously)
#define DEFAULT_XYJERK 15.0 // (mm/sec)
#define DEFAULT_ZJERK 0.4 // (mm/sec)
#define DEFAULT_EJERK 5.0 // (mm/sec)

Enjoy.

---

My printer: Raptosaur - Large Format Delta - [www.paulwanamaker.wordpress.com]
Can you answer questions about Calibration, Printing issues, Mechanics? Write it up and improve the Wiki!

Hey Paul!
Thanks so much for the info! Unfortunately, I won't be able to try it out for a day or two.. it's what you get for being an old disabled fart! LOL
Anyway.. Will definitely look into all the different things you brought up and will give you a status when all is done.

Quick question though, I have an iPrusa wanna-be with 2 - Z steppers. One is attached to the Z axis driver, the other is attached to the E1 driver. Any suggestions on how I can set both stepper currents at the same time without totally torquing the frame in the process?

Again.. Thanks for your help!
Don W.

It is common to connect both Z to the same driver, then it can not get out of sync.
I have a Delta printer so I have no experience with what issues that causes (extra heat in the driver etc).
So, someone else please comment...

Do make sure you have a good fan blowing on the drivers.

---

My printer: Raptosaur - Large Format Delta - [www.paulwanamaker.wordpress.com]
Can you answer questions about Calibration, Printing issues, Mechanics? Write it up and improve the Wiki!