This section describes techniques (some lesser known) to resolve issues commonly faced during tuning of your 3D printer.  However please note that this information is based on our actual work on Nuvogenie 3d printer and experience with other 3D printers we are associated with; so please use your discretion while applying these techniques.

Please write to us at   nuvogenie3dprinter@gmail.com  OR  support@nuvogenie.com  OR via contact us form, in case you would like to share your experience and propagate this to the larger community. Your comments/suggestions are invaluable to us and will be shared with larger audience with due credit to you.

 

Heated Bed Optimization

Want to get rid of that heated bed and instead print on bed at room temperature- try this out:

Generally as a user, preference is to print on cold print bed and avoid using heated bed as the removal of sticky filament after the printing becomes messy. However, when printing on cold bed, the most common problem is the first layer not sticking to the bed surface.  If you are one of many users who have seen their object knocked off in the middle of a long print due to ‘non-adhesion’ of object to surface then do not worry; you are on right track to learn 3D printing and with little techniques this problem can be resolved.

Typically ABS material is more difficult to stick to cold bed, but it is true for PLA as well. Solution could be as simple as:

  • Use of a masking tape or Kapton tape to cover area slightly larger than the base of object that is getting printed (refer pic below). Kapton tapes are more expensive and may not be  easily available local hardware shops.
  • Use of hairspray on bed to increase adhesion
  • Adjust height nozzle so that it is between 1/3 rd to ½ the layer being printed (for example for a layer height of 250 microns (0.25mm), the recommended distance of nozzle from heated bed is 100 microns). This approach works well with Nuvogenie 3D printer, you may have to refer to your manufacturer’s instructions if you are using a different printer.
  • Fatter extrusion layer for first layer can help resolve the adhesion issue as more material means more adhesion.

For the record, we have successfully printed ALL objects shown in Sample prints (and more) without using a heated bed.

Facing trouble with object warping / object getting knocked off:

While 3D Printing is more in line with ‘one setting fits all’, some minor adjustments are required while using different printing material and the shape of object.

ABS is more soft & flexible as compared to PLA and objects with ABS result in better print quality but it has tendency to warp easily and does not stick to base plate properly all the time. On the other hand, PLA is easy to stick to the bed surface even at room temperature.

  • Use heated bed for ABS printing; ensure temperature of extruder is set to about 230 degrees and heated bed is around 90 degrees.
  • PLA can be printed with bed at room temperature by following recommendations in earlier section. Maintain nozzle temperature around 195-200 degrees. Printing at higher temperature than this range can overheat the filament resulting in giving clogged finish to the printed object.
  • Enable the Brim OR Raft settings in slicing software to ensure improved adhesion for first layer for both ABS and PLA. Raft results in an additional thin layer where as Brim provides additional width to the perimeter for first layer.
  • Enable auto cooling setting in slicing software when printing in PLA (may be after 5 layers). Avoid enabling this setting when using ABS as the air from air has tendency to warp the printed part
  • In ABS, if object warping is happening at a height, then ensure that printing speed is correct; reduce if needed to provide time for cooling of the object.

Bed leveling adjustment

Printer does not have auto bed leveling feature; try this to level printer bed:

First of all, as a user, you may want to understand bed leveling.  A leveled bed plays an important role in determining the quality of your print. A leveled bed vis-à-vis your extruder is a must have before you print an object. Typically, there are 2 reasons why you need to level your bed:

  • Based on the layer height to be printed, the bed would need tuning before start of print; especially when the layer height has changed from earlier printed object.
  • Micro variation of bed over a period of time of usage

The height should be adjusted and checked near all the four corners (about diagonally 10-15 mm away from print bed corner). To do so insert a bond paper that is typically 100 microns thick to gauge the gap between extruder tip and print bed. Height can be increased or decreased by rotating the spring loaded screws. As explained in earlier section, this height should ideally be maintained between 1/3rd and ½ of the layer height.

While some printers come with ‘auto bed level’ feature, this can be done manually too. Nuvogenie 3D printer has an optional feature for automatic bed leveling.

 

Filament and feed rate adjustment

Confused about which material / filament to use for printing, read this:

Though ABS and PLA are commonly used materials in 3D printing, many users have showcased good quality prints produced using Nylon and Wood filaments. The material you choose really depends upon multiple factors:

  • Application of printed object: If the object is subjected to bear load to some extent, ABS is recommended because of its inherent load bearing strength and elastic nature. PLA is biodegradable and relatively brittle in nature than ABS. For items that are only to be showcased without subjected to load, PLA is a good material for printing.
  • Ease of printing: Typically PLA is relatively easier to print as compared to ABS.
  • User experience:  If you are a new user to 3D printing, we recommend starting with PLA before moving to ABS.

Typical issues related to Filament - too much filament extruded OR filament deposition is uneven OR very less or no filament extruded:

However good your 3D printer is, it is imperative to use a good quality filament to produce best quality prints. There are some cheap filaments available in the market which when used may not give best results. Even with good quality filament, tuning your extruder for proper feed rate is extremely critical.

  • Filaments generally come in standard sizes of 1.75mm and 3.0 mm and have tolerance levels mentioned as part of specification. As good practice it is recommended to measure the filament size and make adjustments to the extruder feed rate in accordance with the deviation in diameter. Measure the diameter of the filament at various places and then take an average reading. Adjusting extruder feed rate can be done by altering the firmware settings or changing the slicing software settings (eg Slic3r). In Slic3r, change the extruder multiplier to 1.xx or 0.9xx to increase or decrease the feed rate.
  • Many filament issues can be eliminated by pre-heating. So before you start printing, ensure the extruder is pre-heated (can use Pronterface heating option) to 195 degrees if using PLA and 230 degrees for ABS.  Extrude about 5-10 mm of filament and remove all blobs clinging to the extruder tip after pre heating and before start of actual printing.
  • Enable the skirt option in your Slicing software to ensure the extruder is primed before actual printing of object starts.
  • Also ensure that your filament is not entangled in the spool and it is free to rotate when extruder is drawing /pulling it.

 

Speed optimization

Generally, the higher the speed rate, the faster an object can be printed. Consequentially, an adverse high speeds has detrimental effect on the quality of printed object, so there is a need to balance speed against quality.

Skipping steps - If the firmware is incorrectly configured with high acceleration setting, there are chances that the stepper motor would skip steps while rotating. This can lead to incorrect dimension of the object being printed in X and Y directions. If this situation occurs in Z axis motors, it can lead to distorted layer height. This can be best corrected by changing the acceleration settings in the printer firmware. The issue of skipping steps might occur in case the stepper motors are deprived of enough current to move them at high speed. It can be corrected by changing potentiometer setting on the printer hardware board.

Do not worry, the Nuvogenie 3D printer is well calibrated and tested for these issues and you will come across these issues rarely in this printer.

High acceleration setting in the Slicing software can also lead to above issue, so need to ensure that the acceleration setting is tuned between 3500 to 4000 mm/min for optimum results.

Extruder feed setting - This setting is critical to enable the extruder to draw and deposit adequate amount of filament during printing. The firmware for Nuvogenie is well calibrated for 1.75mm filaments. However due to slight variation in filament size the extruder federate can be altered by 5%. Refer the section related to filament above.

 

Slicing / Printing optimization

First layer settings are critical for good adhesion. Please also refer the heated bed optimization and filament sections above to understand this better. The speed for this layer is recommended to be 40-60% lowers than perimeter speed.

Perimeter Speed setting between 60mm/min to 80mm/min produces good quality parts. Lower values of 40 may be required for smaller parts. A high perimeter setting may result into extra filament coming out of nozzle resulting in high wall thickness and small inner areas like holes etc. To increase the printing speed the internal perimeter speed can be set slightly higher that external perimeter.

Small perimeter speed is a very powerful option available in Slic3r slicing software. Perimeter speed is overridden by this option for all speed values below this value that is very helpful in printing small circular openings.

Infill density of 0.2 to 0.25 is good enough for many practical objects. Higher infill density results into oozing of the filament outside the perimeter boundary therefore reducing the surface quality of object. In Slic3r selecting fill pattern as line and top/bottom fill pattern as rectilinear produces optimum result.

If you are printing an object that will not be subjected to high mechanical load, then it is recommended to check the flag for “Solid infill only where needed” in Slic3r. Also the option “Solid Infill every x layers” should be set to 2 or 3 as this will reduce the time taken to complete the print substantially.

Set Cooling fan option to turn on only after first 4-5 layers are printed. This will give better adhesion of object to the print bed and warping of object in the initial stages. In Slic3r the fan switching can be controlled based on the time spent on each layer; for less time spent the fan be switched to cool the layer faster.

Support material generation should be enabled if there are large overhangs in the object.

Spiral setting option should be enabled if you are printing flasks or vases or containers; this option ensure the seam of layer height change gets distributed across the circumference of the object giving smoother surface finish.

Skirt setting should be enabled to prime the extruder with filament before actual printing of the object starts.

 

Other Optimization Techniques