Nozzle double-dipping at start?

[Rejutka 3]

This probably isn't really a Cura problem, but rather user error or firmware "feature".

But I hope someone can enlighten me because it's quite annoying and I'm in a foul mood already (not because of this, but once in a bad mood, everything will make it worse :-/ )

Here's the situation:

I want to print an item. As usual, the head goes to 0/0/0, lifts a bit, extrudes filament.

Now it usually goes straight into the middle to print, but sometimes (as in, some models, not all of them - but it must be in the GCode, it's consistent) the head is lowered again, and it moves very close (I think at printing height) across the bed, dragging the pile of extruded filament with it.

What it usually does is go to the middle, lowering the head while doing so, thus NOT dipping into the discarded pile of filament.

Did I spoil the settings somewhere? I'm quite certain it doesn't always do that. Though I don't keep book about the things it does...

Cura: 15.04.3

Printer: Wanhao Duplicator i3

Windows 7

[Rejutka 3]

No replies yet - no one else has this problem?

I *think* I may have found the reason, but not the why.

These lines seem partially redundant:

 

;LAYER:0M107G1 F2400 E-1.00000G1 Z0.075                                <--- What is this for?G0 F5400 X97.500 Y65.481 Z0.300

 

Why the G1 move? This must be the double-dip, but what purpose does it serve? I don't think it happens always, just with *some* models I'm trying to print?

Also, I know this is an outdated version of cura. I'll switch to the new one eventually, but for now I feel more comfortable with this and I don't want to learn a new Cura and calibrate the printer (the latter is bad enough).

Edited October 9, 2016 by Guest

[geert_2 407]

I don't know the G-codes, but I had this too a couple of times. I don't know why. After loading the model again in Cura and saving it again, this problem vanished. A bug?

When comparing G-codes of a good and bad model (from the same STL-file), there were indeed a few extra lines of G-code in the bad one. After removing them, it went all right too. But I don't remember which codes I removed.