Oh, and your bottom/top thickness should be an exact multiple of your layer height.
Oh, and your bottom/top thickness should be an exact multiple of your layer height.
I'm not sure about the X on the bottom - it would be useful to see the STL file - perhaps there is something about how it's modeled that makes Cura do a strange move, rather than treating it as a continuous outline. I suspect that's also the cause of the trash sticking out from the surface of the print - the head is making long diagonal moves, and oozing while doing so. Do you have retraction turned on, and what is your travel speed set to?
When I printed a second similar part, with layer height set to .1 mm the X at the bottom did not show up. And the trash sticking out of the sides also did not happen again. When I printed that second model again with minor modifications, no X on the bottom, but the trash on the sides happened again. Each time the trash happened I could clean it off the finished print, but I would like to avoid it altogether.
I don't know how to turn retraction on or off. The only place where retraction seems to have settings in Cura is in the Expert config window. I have minimum travel at 1.5, combing turned off (as per your earlier suggestion), minimal extrusion 0.02, and Z hop at 0.075. I just tried that last one, without really understanding what this would do, because the hover over balloon in Cura suggested it.
I don't understand why you're printing a first layer height of 0.1mm on something like this. You're just making things hard, for no real benefit. Set the first layer to something thicker, like 0.2 or 0.3mm, so you don't have to worry so much about the leveling clearance. You've actually gotten the bed almost perfectly level it looks like - just fractionally too close to the nozzle - perhaps as a result of leveling when cold, so that thermal expansion reduces the clearance when the nozzle is hot?
Equally, a layer height of 0.06mm seems excessively thin for a mechanical part like this.
Frankly I don't really know why I chose a first layer height of 0.1 mm, and I changed it since to 0.2 mm. The bottom layer looks a lot better now. I made a print with a brim setting at 20, which gave me a lot of time to fiddle with the screws under the build platform to get the first layer to look better, before the printer started printing my model. I think this may have worked.
I don't know yet what layer height to choose for what models, and I have set the layer height to 0.1 mm for my last several prints. Bottom/top thickness at 0.8, which is now an exact multiple of my layer height.
I have been printing at 220 degrees and wonder if that could be a factor regarding the trash out of the sides.
What do you think about printing just the first layer at 220 degrees and then dropping down to 210 or even lower? Do you have a suggestion?
Last question. What is the difference between Skirt and Brim?
Brim circle around the edge of your initial layer (outside and inside) while skirt does only the ouside and doesnt touch the model by default. Brim add stability to thin structures that will grow high diring the print while skirt doesnt do anything except giving you a hint about your bed leveling. You can see both in the layer view in Cura.
Retraction can be enabled using the Enable Retraction option just under the shell thickness setting in the basic tab. If Retraction was active try printing at 210C instead of 220C or change the retraction settings directly in the Tune menu on your UM2. Try making the retraction length 4.5mm and speed 45mm/s.
I use 0.1mm height for most prints unless I do figurines or more organic prints then I use 0.08 or 0.06 for higher quality.
Recommended Posts
illuminarti 18
I'm not sure about the X on the bottom - it would be useful to see the STL file - perhaps there is something about how it's modeled that makes Cura do a strange move, rather than treating it as a continuous outline. I suspect that's also the cause of the trash sticking out from the surface of the print - the head is making long diagonal moves, and oozing while doing so. Do you have retraction turned on, and what is your travel speed set to?
I don't understand why you're printing a first layer height of 0.1mm on something like this. You're just making things hard, for no real benefit. Set the first layer to something thicker, like 0.2 or 0.3mm, so you don't have to worry so much about the leveling clearance. You've actually gotten the bed almost perfectly level it looks like - just fractionally too close to the nozzle - perhaps as a result of leveling when cold, so that thermal expansion reduces the clearance when the nozzle is hot?
Equally, a layer height of 0.06mm seems excessively thin for a mechanical part like this.
Link to post
Share on other sites