Our planes contains parts designed to be printed mostly as single wall prints without support and default infill(it’s replaced by specially designed inner structure) This kind of printing is demanding for printer setup. If you are not sure if your printer can handle this kind of print just download test file from this site. Print our test file with provided print settings.
PLA Printing parameters
3D printing Aero plane is not a plug and play process so we assume you already have some basic experience and due to multiple guides available over internet we will describe just most valid points:
Extruder Calibration – this factor is so important for final result we believe it should be first thing you should check before printing. Use “steps to mm calibration” method.
Basically, you have to set printer hot-end to printing temperature (for PLA ~210C), and activate your extruder by requesting 100mm filament extrusion (make markings over filament for further measurements). When extruder stops, check how much filament has been extruded.
- If less than 100mm it’s under extruded, you have to increase extruder steps per mm.
- If more than 100mm it’s over extruded, you have to decrease extruder steps per mm.
To calculate new value use following formula:
Nozzle diameter – use only nozzles with 0.4mm diameter. Only this size guarantees correct printing of our models.
Printers – Heated bed is obligatory. Minimal build volume is 200/200/200mm (length/width/height), but for comfort usage we recommended printers with build volume 300/300/200 or greater.
Flow parameter is very important for final result. We found good starting value is around 103% of nominal for all printed layers. You should play with this value to get slicer estimated print weight same like it is in PDF user guide (If your extruder is calibrated properly your prints should weight exactly the same like your slicing program tells you e.g. CURA) see Figure 1. Flow for first layer should be slightly increased for better bed adhesion. Lack of flow overall can cause lighter parts but weaker as well.
For first layer use temperature of 230 C (230-240C) degrees to help with bed adhesion, after first layer temperature should dropped to constant 210 C (210-220)C. This values may change for different PLA. Cooling fan should be turned off.
During our research we found good print temperature is balance between layer bonding, and plastic fluidity. High plastic fluidity caused by too much temperature is one of major reasons why you could get empty spots caused by oozing filament (usually after hotend long non print move) see Figure 2. On other hand dropping temperature too much cause prints to be brittle with little of layer bonding. We recommend setting the temperature at 210 C (210-220C) which is good start point for many PLA filament available on market.
Bed Temperature/Bed adhesion
Bed temperature is all about bed adhesion. For making printing process easy and stable we strongly recommend that your printer be equipped with adhesion pad if you don’t have it already.
First layer should be printing with temperature around 60 degrees and with speed of 30mm/s, this setup guarantee’s proper first layer adhesion, for next layers temperature should dropped to c.a. 48 degrees to avoid overheating layers close to heated bed. Don’t forget to clean your heated bed from time to time with isopropyl alcohol to keep away greases and other contaminants
It’s strongly recommended to use print seed of 40mm/s. It’s optimal for most of printers if you want to print single wall prints. Higher speed can result in under extrusion causing brittle parts. First layer should be printed no faster than 30mm/s to achieve good bed adhesion.
Retraction prevents oozing during non-print movements. It’s heavily depends from extruder type.
- For bowden extruders retraction distance good starting value is around 3.9mm. To prevent under extrusion at layer start point retraction should be combined with use of “Retraction Extra Prime Amount” (extra restart distance) usually around 0.16mm3. All values can depends from bowden length, curvature, bowden attachment play and filament type.
- For direct drive printers good starting value is 0.8mm
All parts are designed to be printed with 0.2mm layers thickness, which is suitable for most printers.