Lite6, ABS and PETG Skipping

Hey,

Recently I got a heated bed and I've been trying to print ABS and my extruder skips on speeds higher than 35-40mm/s. This results in a temporarily under extrusion which shows like a missing layer on the prints.
I'm able to print PLA at 75-80mm/s with ease and good quality, so I'm wondering why I can't do the same with ABS or PETG?

I'm using this extruder: http://www.thingiverse.com/thing:275593/
I tried a range of temps from 215 to 242 for ABS and the extruder always skips on higher speeds like 50-60 etc...
I can print ok at about 35mm/s, but even then it sometimes skips but it is VERY rare at that speed.

My filament is measured and set at 1.8mm in the settings. My nozzle is 0.4mm.


Btw I'm not sure if skipping is the right term so I'm just gonna explain what happens exactly.
What I mean by "extruder skipping" is that the extruder jumps back and forth for a few seconds and the filament doesn't move. It looks like filament doesn't have any room to go forward, which makes all this happen.

Thought a photo might help:
This was done at 40mm/s and I even reduced the speed by 15% half way through and it still didn't help. It wasn't this bad yesterday, I was able to print fine at 40mm/s.


Edited 1 time(s). Last edit at 06/18/2016 09:15PM by White.Renard.

ABS likes slow speeds, 30 mm/sec at those posted temperatures is good, you should not get any skipping.
For faster prints 50 to 60 mm/sec you need to be in the 250 mark which your hotend will not reach without serious damage to the PTFE liner.

My advice is to check the extruder for loose idler, filament in the gears and verify that the stepper driver is set correctly.

If you printed PLA before try a "cold pull". It helped me on non-lite v6

Whilst ABS may be slower than PLA, I completely disagree that it needs to be as slow as 30mm/s ... I regularly run ABS at 60mm/s between 232 - 242 depending on filament using mk10 extruders.
With higher speeds you need to ramp up the hot end temp a little to keep the ABS flowing cleaning.

Sounds more like you need to increase your extruder stepper current, if not possible then you have reached the limit of your extruder set up

Thank you everyone for replying!

I've tried high temps like 242 at 40mm/s before and I still experienced the skipping.
I've checked the tension, mk8 gear and current. I actually increased the current a bit more than the stepper (Stepper is 1.65, now I have it at 1.7). Now I'm gonna try to print at 50mm/s see if anything has changed.
Haven't tried a cold pull yet, but I will.

My stepper's torque is 3.5 kg/cm btw.


Someone on the E3D forums suggested I'd use a wade's extruder. I'll do that, but I gotta order some hobbed bolts first.
In the mean time, is there any Wade extruders that actually use MK8 gears instead of hobbed bolts?

Lite6?

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

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