Hi!
I just started 3d printing and I have an issue.
When I print I get layers (that is not on the STL-file or x3g) on the buttom of my print. Once the print is done I am struggeling to get this away.
Any idea why it does this and how I can remove it? The printer is a CTC Markerbot Replicator 2.
I will attach two images. This first one is from underneath showcasing my issue. The layer there is not on my stl/x3g and I do not know why my printer gives it that extra layer.
If you instead look from above the design looks pretty nice (aside from the layer underneath).
Is it something to do with shadows and if so, can I disable that somehow?
Appreciate the help alot! 
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To me it looks like your setting are set to print with a brim. This is usually just a checkbox in your slicing software.
Brims are generally used to help thin parts stick to the bed by creating more surface area.
Looking at this part, you shouldn’t have any issues printing it without a brim.
Hope this helps!
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I found something called “Fixed Shell Starting point” and I had it checked in my checkbox. Could this be the one I should uncheck?
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Nope, that’s when you want the printer to start every layer from a fixed point, let’s say for example from the front-left corner of your model, if you uncheck it whenever a layer is finished the bed goes down and the printer continues the print by starting the new layer wherever it finished the last one. You need to uncheck the raft to get rid of the extra layers under your model or if you want to keep it but make it easier to remove you need to change the model spacing from raft (like add 100microns).
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You are printing with a raft. This is an option for helping prints adhere to the bed if they have a small footprint and a couple other special circumstances. I don’t have any experience with the software you’re using but I’m sure there is an option in the slicer to turn it off.
Hope that helps.
-Jesse
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Ok! I tested a print and unchecked “raft” completely. The outcome was that the PLA on the printer got stuck like a “blob” on the outside of the nozzle. Is it because the printingboard was a bit to low compared to the nozzle or would it be something else?
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I turned off “raft” completely and tested a print. The outcome was that the filament (PLA) got stuck on the outside of the nozzle. Any idea why this happened? Was the boardlevel (heating board) a bit off maybe?
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Raft is not just to give your model a good grip to the bed but also levels your print even if your bed is not properly leveled (a little bit). So if you remove the raft you need to precisely level your bed and make sure the nozzle has the same distance from the bed at all points and that distance would be like the thickness of an A4 paper for printing 200microns and above. For like 100 microns you need to bring the nozzle closer to the bed but make sure it doesn’t scratch your bed. If you see leveling is really hard for you to do use the raft but play around with the model to raft spacing to find the sweet spot where you can easily remove your model from the raft and it doesn’t detach during the print.
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What material is the bed and is there anything on it(painter’s tape? glue stick?)? Are you printing the first layer at a slower speed(this would be a good thing)?
I think a thin layer with a all-purpose elmer’s glue stick will solve your problem.
-Jesse
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Really struggeling with this. The bed is now almost scratching the nozzle because it is very close (A4 paper just gets through) but still the filament (PLA) gets stuck on the outside of the nozzle.
Maybe I should print with a raft but change the settings to make them easier to be removed. My hands are very soar from last night though when I tried to peal them off… 
Should I adjust the raft move speed? Or would increasing the raft layer height make it easier to remove? Adjust raft infil to maybe make it less compact?
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I decreased the speed for the first layer to 15 (from like 40(?) i think) but this did not help.
This is the exact printer I have:
The bed is covered by a blue material but I am not sure what it is called.
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Raft speed by default setting must be good. If you are using MakerDesktop then you can go to the settings->custom->presets(you need to select one or duplicate and then edit it)->raft->raft to model spacing which by default should be 290microns for 400microns printing. First test it with 400microns and see if it prints well, something small like a calibration box and try to remove it, if doesn’t come off easily then increase the spacing. Another thing, before printing try to load the filament and see how it comes out of the nozzle when the bed is not close to it. it should come out straight without turning to an angle and get stuck to the nozzle. Clean the nozzle if needed when it’s hot (be careful). At 215C it should come out easily and straight otherwise you need to take the nozzle out and clean it from the inside, sometimes filaments contain unwanted material that get stuck into the nozzle and you need to pull them out from the inside.
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That’s probably blue painters tape. Put some glue stick on top of the tape and it will stick to the bed instead of the nozzle.
-Jesse
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Okok! I will probably try that then! Will there be any problems after if glue gets stuck on the bed?
Use a thin layer. It just makes the surface tacky. Glue stick washes off with water.
-Jesse
Okok! I dont have any current glue in my house but will get it tomorrow and try it out! Thx alot for the help!! Meanwhile I will do some more research how you can make a better raft
Also, there should be an option to increase the first layer height. This allows you to lay down a thicker first layer without affecting the resolution of the rest of the print. Just don’t make it larger than 80% of the nozzle diameter.
-Jesse
Maybe I did not check carefully enough but on Makerbot I cannot find a setting where I can adjust the first layer height. I can adjust the printspeed of the first layer but that is about it. Hmm, maybe I should look for another solution than Makerbot?
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Makerbot Desktop does not have that feature, it jut gives you the speed control and cooling for the first layer, you can use simplify3d to adjust the first layer height. It should work with your robot.
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