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Maintenance
8.12
Check tension and wear of belts
Maintaining correct tension on the belts is important to ensure good print quality. The belts transfer the
movements of the motors to the slides. If the belts are too loose, print head movement may not be accurate,
which can cause print inaccuracies. Over time, the belts may become slack. It is recommended to check the
tension of the belts at least once every three months. Pluck the three belts to check their tension. They should
resonate, like a guitar string. Furthermore, the tension of the three belts should be equal.
To restore the tension, perform the following steps:
1.
Home the printer (make sure the slides are all the way up)
2.
Sent printhead down in the middle to 1000mm
3.
Loosen the bolts of the idler pulley (up in the printer) with only 2 turns (don’t unscrew them completely)
4.
Push the idler unit firmly up with your hand or a tool
5.
Tighten the two screws of the idler pulley unit again to fix it.
6.
Repeat this for all three belts
7.
Make sure all belts are feeling the same in tension
8.13
Check if print head fan is running after heating up
The small fan on the print head cools the print head during a print. This helps to prevent the heat from the nozzle
traveling too far upwards. The fan takes in air from the front of the print head and directs it towards the metal
cooling ribs of the print head. Sometimes the airflow causes thin strands of filament to be sucked into the fan
during a print. If strands accumulate in the fan, they can decrease the effective cooling and eventually obstruct
the fan and prevent it from spinning.
