Mini Shredded Wheat Type Prints

Hi all,
Could I pick the brains of the collective please on my first prints that I made this morning.

I am using Slic3r and Prontaface and am using PLA. I have a Mk2 heated bed. This is not temperature controlled at this point but left for 10 minutes or so to get up to temperature. Oh, I am printing the 20mm cube calibration object on glass and the hotend is 185 degrees.

The first layer seems to go OK (ish) it's a bit gappy in places but does look fairly neat. I am sure with some tweaking I could make this OK.

However, the next layers look a real mess, according to some unkind people, like Shredded Wheat!
Eventually the hot end starts to clog up and I have not been able to complete the prints.

I have attached some photos if that helps visualise things.

Any ideas on what I should be focussing on to sort this out?

Any help would be appreciated.
cheers
Mark.

The gcode looks ok, so it seems like a mechanical issue.

Focus on the hot end to make sure it extrudes smoothly and have good grip on the filament.

You don't say which type of hot end you have, but several (most?) designs benefits from a fan cooling down the upper part of the hot end wile printing PLA. Could be heat travels up the inside the barrel making the filament soft? The filament also looks a bit discoloured, as if too much heat was used?

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-Nudel
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Also, check your z-axis steps per mm. It may be moving up much more than the extruder expects, so each layer can't bond to the previous layer. Move the z-axis up 20mm in your host software, and measure if it actually moves that far or more.

Thank you for the advice gentlemen.
I checked the z-axis movement and, as far as I can tell with a ruler, it moved 20mm when when told to.
I tried different temperatures etc. The 2 things that I found that made a big difference was the speed and also adding a fan. Though the fan seems to benefit mostly on cooling the PLA as it is printed to give a better base to the next layer. I assume this is because it is a relatively small object that I am seeing this.

The photos attached are the 11th attempt (200 degrees C), 12th (210 degrees) and 13th (210 degrees and 0.035 layer height.

These are a massive improvement but obvioulsy still a long way to go.

To start, any suggestions on the gaps to get rid of the mesh effect?

Thanks as always
Mark.

and... I have Parcan's Mk2 hotend.

Double check the nozzle size, it looks a little off on the walls (could be the x and y axis but check the nozzle first).

If the nozzle size is correct then try one of the hollow calibration objects (with with the base and wall). It could be the belts or x/y steps per mm.

Edited 3 time(s). Last edit at 02/12/2012 03:04PM by JoeDaStudd.

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It looks like your belts are not tight and you are getting some lash.