Can't seem to improve the hollow pyramid print

I've got a PLA RepRapPro mendel (was tricolor, but I've now got it running a single extruder and have replaced the Melzi boards with a RAMPs board), and I've sat down and calibrated it (or so I think) to the best of my ability, measured my filament, used the median as the filament width etc, however I can not get the hollow pyramid print to print well

I'm using 4mm retraction, printing at 205c, and with a big fan from a server blowing over the print bed (did install a nozzle fan today though, didn't make any noticable difference)

See

Hollow Pyramid print errors

I'm using Slic3r, I haven't got my head around Skienforge yet!

Any suggestions as to what I should be trying next?

Cheers

Definitely lower your temperature. Try to start at 190c and increase as needed. What nozzle size and layer height? What version of Slic3r? Is it the latest, or the one that came with your Pronterface (Printrun)?

Sweet, will try with temp around 190c, the nozzle size if 0.5 (I think; I've measure free air extrusion, and tried measuring the hole with a microscope and it all points towards 0.5 than 0,4). The layer height I've been using is 0.25, and the version of slic3r is 1.1.7.

Well, I dropped the temperature and didn't make much difference. I did how ever manage to finally wrap my head around the basics of getting a print from Skienforge, and managed to print the a movember ring quite successfully, just this hollow pyramid doesn't come out well, is it actually a hard object to print? Am I running before I can walk!

Anyway, with Skienforge and the temperature set lower, I seem to be getting tidier prints...

Still a lot of learning yet!

Those layers don't look like they are laying flat enough. If you are printing at 0.25 layers, I'm thinking you may have a 0.3mm nozzle. Try changing that in your slicer and dropping layer to 0.2mm. Make sure your fan is not blowing on your nozzle. This will cause it to run hotter to keep up. You may need to print a cone for your fan to direct it to the print.

A bit of an update, I lowered the temperature a bit, the prints improved, but it looked like I had moisture in the filament (was not sure though, only had the filament for a week!), After taking to the manufacturer of the filament, they suggested going even lower, now extruding at 170. The prints are improving, still looks like I'm putting down too much filament though. I will remeasure the filament and try again.
I also identified several other problems, there was significant backlash (0.9mm) in the X axis due to some screws being too tight, and there is some (unsure of the quantity yet) in the Y axis, I think some of the backlash is due to the belt slipping of the bearing near the Y stepper motor.

I can print cubes fine....anything with some more complex moves, and the layers don't line up!

P.S., the belts seem nice and tight, (but not overly tight).

Once I get a bit further one, I'll post some more questions about locating and removing backlash.
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