Printing inconsistencies

[Culyx]

I've got a lot of bugs sorted out and my E3d extruder is in place and working correctly now (yay!), however my first larger print turned out to have some "thinning" of the deposits on the piece. [img]http://i.imgur.com/sWPRnlT.jpg[/img] The bottom is solid and the top looks pretty good, just a few spots on the way up look thin. I did some digging and thought it may have been the extrusion retraction speed?

Listed here http://forum.seemecnc.com/viewtopic.php?t=10435 and linked to http://wiki.e3d-online.com/wiki/E3D-v6_Troubleshooting both of these seem to be likely culprits?

The newer print at a lower retraction speed (hadn't read the bit on retraction length initially) didn't seem to improve things: [img]http://i.imgur.com/Dtg81G6.jpg[/img]

If this is the case what would be some good initial settings? Currently have things set as such: [img]http://i.imgur.com/GMVo9sY.jpg[/img] (these were the defaults) the speed was adjusted to 100 for the second print I made above.

[morgandc]

Pictures didn't come through

[Culyx]

Pictures didn't come through

Oops sorry fixed those up.

[Polygonhell]

6.8mm is way too long a retraction for an E3D type hot end. I'm surprised it didn't just jam entirely.
The old RM hotends needed a lot of retraction and that generally resulted in having to use a very fast retract.
I'd try 1.5mm retract @ 25mm/s, I run 1mm ZLift but it's not always a win.
MHackney recently posted something on retraction setting for the HE280 which is a lot like the E3D.

[IMBoring25]

Yeah, I, too am shocked that worked as well as it did on PLA (?) with that much retraction on an E3D. I'm using 2 mm at 10 mm/s on mine and it's especially critical to use short retractions with PLA.

[mhackney]

This is classic filament starvation and could very well be due to that very long retraction plugging the E3D.

You basically do not want to retract the molten filament up into the heartbreak. 2mm is pretty close to the max. You can stretch to 3mm but anything over that is a disaster waiting to happen.

I've also posted a lot on E3D hot ends. 15mm/s retract speed, 35 mm/s advance if you are using KISS (it's the only slicer that lets you control this) and 1 to 2 mm retract. I usually use 4mm Z lift successfully for most parts. 25mm's retract is a reasonable compromise for most parts with non-KISS slicers. But there are parts with lots of rapid retracts that even this will be problematic.

[Polygonhell]

Actually FWIW the current Cura added separate retract/advance speeds.
I downloaded it recently to see what it's support looked like and was surprised to find it there.

[mhackney]

Thanks Polygonhell. Good to know.

[Culyx]

Yeah, I, too am shocked that worked as well as it did on PLA (?) with that much retraction on an E3D. I'm using 2 mm at 10 mm/s on mine and it's especially critical to use short retractions with PLA.

I guess for the record it's PLA/PHA from colorFabb

[Culyx]

Did a print with the settings at 1.5mm length, 25mm/s speed, and left Z-lift at .3mm and it came out great, thanks everyone!