The head
The nozzle and thermal barrier are consumables and are under constant strain and can wear out quickly. With an unfilled material like a simple PLA, a nozzle (brass or copper) and its thermal barrier have a lifetime of about 600 to 900h. With a carbon loader on the same nozzle, less than 50h… Hardened steel nozzles are therefore imperative for filled materials. It is therefore essential to maintain and change these elements regularly in order to keep optimum performance. Be careful with the positioning and tightening of these elements which must be very precise. Also remember to change the PTFE guide tubes from time to time. Also note that changing the nozzle and the thermal barrier can be done separately. Nevertheless, we strongly recommend changing them together to avoid redundant problems. In any case, if you do not have a spare head, we recommend that you purchase one (https://www.imprimante-3d-volumic.com/fr/pieces-detachees-imprimante-3d-volumic-stream.cfm). You can change it directly to take the time to install a new head without stopping the machine.
The extruder
For maximum performance and to avoid slippage and blockages, the main elements of a maintenance are :
- The condition of the drive pulley is always sharp, the teeth are clean and free of clogging
- Tightening the screws of the extruder motor. Check the tightness of the screws to make sure nothing is loose.
- The condition of the compressor bearing (if it is loose, even slightly, do not hesitate to replace it) and the condition of the compressor itself (no cracks or deformation).
- Also check the head fans. These must run perfectly without the slightest cut or micro-cut. A poorly cooled head is sure to cause filament blockages.
The belts
Check the belt tension from time to time. It is not easy to find the ideal tension for the belts, but these elements will allow you to better refine your adjustments. Too much belt tension will cause the motor to strain, resulting in more and more lag during printing. On the other hand, a belt that is not tight enough will generate more and more “Ghosting” on your print. This phenomenon may distort the circles into ovals. The perfect setting is a belt that is optimally tensioned without causing shifts.
The mechanics
In order to maintain maximum quality and precision, the screws are an important monitoring point. Due to the constant vibrations caused by the printing process and the hot environment, the materials tend to work and the screws tend to loosen. Tightening all the machine’s bearing bolts every 1000 to 2000 hours of printing will help you keep the best quality. Tighten all Z-bearing screws. In particular the top and bottom of the machine, the tightening of the motors and belt pulleys, and if necessary the bearing housings under the heating bed. The ideal tightening torque for all holding and structural screws is about 1 to 1.2Nm
The material
The filament in an open, unused spool gradually picks up moisture and can become increasingly difficult to print within a few weeks. Many materials are also quite sensitive to UV light which will make them more and more brittle and problematic. The most common symptoms are under-extrusions, wire breakage and untimely clogging. The print quality will also suffer (rougher surface, bubbles…). Keep your reels away from light, in a rather dry, cool place (-25°C) and in a closed bag with anti-humidity tablets. Monitoring the humidity level may be necessary depending on your environment, but in any case, an open coil should be consumed as soon as possible to reduce the risk of problems.
Cleaning
Clean your machines regularly and remove any waste that may accumulate inside. These are quite dangerous for the belts and bearings if they get caught in them. Also blow out the fan inlets to remove accumulated dust (motors, electronics box, power supply). Clean/blow out the extruder drive regularly to prevent it from accumulating too much dust and waste. A poorly cleaned drive will not have a good grip on the filament. Never spray lacquer inside the machine. The lacquer will stick to the shafts and will quickly deteriorate the ball bearings of the linear movements and will clog the cooling fans which will result in a decrease in performance.
Greasing
It is important to grease the pins and bushings when you feel them getting a little “dry” to the touch. Grease the axis along its entire length, spreading the grease over the entire surface. Then move the shaft in question several times so that the ball bushings collect grease and lubricate themselves inside. Use liquid PTFE grease and avoid standard mechanical grease that will tend to dry out and become sticky, which will decrease the performance of your machine and may even lead to malfunction.
