Perimeter porous Geeetech i3 M201

I have test printed a 20mm cube, and the sides and top are incomplete, but the base is ok;
https://dl.dropboxusercontent.com/u/.../20mm-cube.jpg

I have increased the extrusion multiplier from 1 to 1.25, which helped.
I have also made these other changes to see if they would help, but i cant tell any difference;
Extrusion Width → Top Solid Infill 0.45 to 0.8
vert shells 3 → 6
horiz shells 3 → 6
Default extrusion width→ 0.3 to 0.4

Are people having success with ABS using Geeetech's slicer settings from;
http://www.geeetech.com/wiki/images/4/4 ... config.zip
And if you had the change them, what did you do?

That looks a total mess i am afraid to say.

It is massively under extruding. Have you checked the extruder and the nozzle for a mechanical issue?
What hot end temp are you using?

I would also check that you have the correct steps/mm for the extruder.

Is this your first print? has it printed ok before, if so what has changed?

The image reminds me of cases in the past where people were using 1.75mm filament but the slicer was set for 3mm.

I would verify the extruder is putting out the correct amount of filament and calibrate that. Mark 100mm of filament, and tell the extruder to extrude 100mm. It better be very close. Also verify your nozzle diameter is correct in the Slicer program you are using.

Ok, i've upper all 5 stepper motor drivers from 0.5x to 0.9x volts. No effect on print quality,

Thanks all for your responses.

>It is massively under extruding. Have you checked the extruder and the nozzle for a mechanical issue?
What hot end temp are you using?

The hotend is the gimmickly dual feed unit that comes with the M201. I have set it to 50%/50% feed since im not interested in that feature. Temp is set to 240 deg celcius, but IIRC it starts printing at 235.

>I would also check that you have the correct steps/mm for the extruder.

Where is that setup? I'm using RepetierHost and slic3r.

>Is this your first print? has it printed ok before, if so what has changed?

Yes first prints after building it. Newbie here.

>The image reminds me of cases in the past where people were using 1.75mm filament but the slicer was set for 3mm.

Double checked that, and its setup in slic3r for 1.75.

>I would verify the extruder is putting out the correct amount of filament and calibrate that. Mark 100mm of filament, and tell the extruder to extrude 100mm. It better be very close. Also verify your nozzle diameter is correct in the Slicer program you are using.

Ok will do.

Ok the filament use is a tiny fraction of the requested feed, maybe 10mm out of 100. One of the extruders drive had significantly less grip than the other, so i've stretched the spring and re-installed, but no help. I also tried increasing the hotend temp from 240 to 250 and reducing these settings;
Rep host -> config -> printer settings -> printer
changing manual extrusion speed
left box 2 -> 1, right box 20 -> 1 (units mm/s)

Rep host -> config -> printer settings -> extruder
max volume per second 12 -> 4 (mm3/s)

But none of that has helped. Next i tried removing the fans from the extruder drives and confirmed that the filament is slipping in the drive, so its not a problem with voltage to the stepper motors. With the PTFE tubes removed from the hotend the full 100mm comes out. So I either have a problem with the level of grip in the drives, or resistance to flow in the hotend, or a combination of the two. I can push the filament through manually. There's a lot of resistance but i'm guessing that's to be expected as there's a solid fat filament that needs to be melted and pushed through a small orifice.

Any suggestions or do I just keep trying to get more drive force onto the filament?

Or do i give up and get a better printer? I've spend weeks on this now.

From a net search "Check the hotend pushing the filament by hand. (245°C for ABS, 200°C for PLA) It should be as easy as inserting a knife into some butter.". Is that right? If so there must be a partial blockage in my hotend because its really difficult to push the filament thru.

Replaced tip - issue fixed.

Actually, replacing the top only helped. The extruder filament drives do not have sufficient grip on the filament and slip a lot. No tension adjustment either...