adrian wrote:

Not scientific, but it at least ensures you have them evenly set: http://www.thingiverse.com/thing:38952

Perfect! A lot better than not too tight, not too lose!

Thank you, Adrian!

No problems.

I also meant to tell you, re your model accuracy, be sure to tick 'External Perimeters First' in Slic3r config - this will draw from the outside inwards instead of the default inwards-out and helps improve accuracy a lot as it accounts for 'ooze' in the plastics much better etc.

Not scientific, but it at least ensures you have them evenly set: http://www.thingiverse.com/thing:38952

Perfect! A lot better than not too tight, not too lose!

Thank you, Adrian!

In Sweden we have the term "lagom" meaning "just right." It's a bit like Goldielock, not too much, not too little. As a Swden, I have the "lagom" concept ingrained in my DNA since time immemorial. But when calibrating the tension of e.g. drive belt, "lagom" isn't the best way to describe the end result...

Lagom: http://en.wikipedia.org/wiki/Lagom

As for belt tension on the long y axis belts, that can affect your binding of the x carriage, and this needs to be evenly tensioned for this reason.

Also, don't overlook loose grub (set) screws and  be sure your rods are clean and greased.

1. and 4.

It might be too thin to extrud infill for that area. Can you post a gcode's image and check to see if plastic is extruded in that area or not. (if it is... it might be retraction)

looks like brim to me.. model with holes will have random brim created for it.. once again. check your gcode's graphical display, and display first layer and see if it's there or not with brim on and off.

adrian wrote:

Your Y-motor belt needs tightening. thats the cause of the oval holes. You may also have problems with your belt tension being uniform, but start with the y-motor.

Just out of curiosity: What makes you target the Y axis and not the X axis?

The y axis is usually just more likely to have issues with multiple belts and shafts you have a lot more tension problems and such especially with environment changes.

adrian wrote:

The one-layer fill could be slic3r, could be the model. Run it through cloud netfabb and see if the problem persists.

Already did. The results are from a netfabb checked STL-file. I tried my own some time ago, that print had a lot of other problems, but the one-layer fill wasn't there.

I have done a few models in sketckup and netfab and some still ended up with problems, I have been using freecad lately and once you get the hang of what not to do it seems to slice better than similar models from sketchup.

adrian wrote:

the off measurements are also due to steps-per-mm, and can also be due to misalignment and backlash in the x/y planes.

You kind of thought that would be correct when you get it from Solidoodle. Print straight out of the box and all...

Well... they didn't say 'prints accurately out of the box'

Your Y-motor belt needs tightening. thats the cause of the oval holes. You may also have problems with your belt tension being uniform, but start with the y-motor.

Just out of curiosity: What makes you target the Y axis and not the X axis?

Already did. The results are from a netfabb checked STL-file. I tried my own some time ago, that print had a lot of other problems, but the one-layer fill wasn't there.

You kind of thought that would be correct when you get it from Solidoodle. Print straight out of the box and all...

The one-layer fill could be slic3r, could be the model. Run it through cloud netfabb and see if the problem persists.

the gaps are indeed flow-rate.. have you calibrated your extruder steps-per-mm and flow-rate as per the wiki ?

the off measurements are also due to steps-per-mm, and can also be due to misalignment and backlash in the x/y planes.

First stop i'd say is bung it through cloud netfabb, check your y-motor is tight without bending the link-rod, do a full extruder calibration of steps-per-mm and flow-rate using a test cube, and then reprint...

The defects:

1. The "gills" are slanted at 45 degrees. They are supposed to be solid, but there's a gap in all of them. It's like if the G-code assumed the walls would meet in the middle. Could this be flow rate (the walls should be thicker, but due to too low flow rate, there're not)? Or is it a problem in Slic3r (a plain old bug)? Or?

2. The two holes are not round. Is this an error in the printer setup (X and Y axis are not moving correct distances compared to each other)? Or?

3. One of the gills got one layer of fill, there should be none. Bug in Slic3r? Or?

4. The join between a floor and a wall leaves a massive gap. Slic3r? Misaligned printer? Or?

5. The overall measurements are slightly off: Length should be 120 mm, it is 120.20 mm. Width should be 70 mm, it is 70.84 mm. X and Y misalignment? Or?