Top layer is rough

[jheikkila54]

Hey Guys,

I have an issue that I cant quite figure out. My solid layers are coming out rough and extruding a bit. I calibrated my e steps and am within 1 mm. I also have "fine tuned" the flow rate using a hollow cube and is within .01 however the solid layers (except for the first layer) look as if I am over extruding or the layers are overlaping to much. I am using a .3 nozzle with .4 layer width and .2 layer height, 2 perimeters, 3 bottom/top layers, printing in ABS at 230. Any help would be greatly appriciated.

[JoeJ]

It definitely looks like you're over-extruding. Keep in mind that you don't want to tune your extrusion multiplier to the first layer, since that will be largely affected by your bed leveling and nozzle location. So if you're first layer is filled in perfectly, but the top layers are over-extruding, you are most likely over-extruding everywhere and also have the nozzle a bit too far away from the bed on the first layer.

Start by decreasing your extrusion multiplier by 0.05 and then run the print again. Once the top layers looks correct, then try to adjust the first layer nozzle height using the gcode z-axis offset.

[jheikkila54]

OK, I will play with that tonight, thank you.

I do want to point out however that I wasn't adjusting my flow rate based on the first layer. I adjusted it based on the measurement of a single wall of a cube. I have it set to extrude .4mm perimeters, and have tuned the flow rate to about .4mm (+/-.02). However, top layers are more important and will will lower the flowrate until I have a good top layers. Also, I am printing .2mm firsy layer thickness, you think this may be to high? I have good success with adheasion at .2, and have read of many that recommend printing the first layer the height of your nozzle size (clearly im not doing that, but thats what I have been reading)

[jheikkila54]

After playing with the flow rate on a couple calibration blocks. I found that I was simply extruding 3 percent to much and was enough to cause a pretty rough top surface. Now the surface looks great! Thanks for the reply