Issue with retraction and restart

[sysgen 0]

I've been having this issue and would like to know if it's just me or something with Cura, or my printer.

If you watch the following video, you will notice near the end at 23s that when it switch from black to blue, the head starts flowing before it is back on the object, of course this creates a lot of defects on the object and is pretty messy. Anyway to avoid this?

 

Otherwise my printer works perfectly and I can print pretty amazing stuff.

I'm using Cura 13.10, I'll try with 13.12 which I just noticed is available and report back here.

 

[sysgen 0]

I noticed there is a new option called Wipe&Prime and also Ooze shield. I'm trying the Ooze shield right now and its looking good!

But my question remains, why is the plastic starting to flow before the head in over the object?

I've had a similar issue with a large piece I did the other day that required a lot of stop and restart of flow, from a single head this time. And a lot of the mess was due to this issue.

Right now my retraction parameter are at the following values

Speed: 50

Distance: 2

Dual Extrusion switch amount: 4

 

[tonycstech 3]

Does it flow by allot or just little bit as if it drips down from being melted ?

What nozzle diameter u have ?

If u have big diameter, it could drip allot, gravity pulls it down u know.....

Something wrong with the code generated. Sometimes i get CURA to generate strange pause/continue, rare but i see it happen on generating code for exact same model same day.

Just restart CURA and regenerate the code to see if it helps.

Lastest version of CURA instead of slowing down last 3 layers of fill, it speeds it up making it ruined.

Dont know why they changed it.

 

[sysgen 0]

it's not dripping, as you can see in the video, all the time the black color is active, the blue head (Left) is not dripping at all, as soon as it switches color, it primes itself and pushes out a little amount of plastic, then it starts moving.

Here's what I think is happening, I have retraction configured for .2mm, so when it switches heads, it pulls back the plastic .2mm and then wait. When the head becomes the active one again, Cura primes the head to bring it back into operation but it seems to push more than .2mm of plastic. What is the value it uses to prime the head? Is this configurable? Or should it be the same as the retraction?

Why doesn't it wait to be over the object before doing this priming?

The nozzle is a J-Head .34

 

[tonycstech 3]

Look into the code. Find the layer at which change takes place and see what commands do what.

Or you can generate small 10x10 cube gcode and upload it here so we can look at it. Just tell us at what layer your problem occures.

All codes are here:

http://reprap.org/wiki/G-code