The correct belt tension is essential to a core XY motion system. A loose belt or belt slop, can cause lots of issues in 3D printing, such as circles looking like ovals.
The belt and the gantry form a mass-spring system, with the belt being the spring (k) and the gantry being the mass (m). The natural frequency of the system is f = sqrt (k/m). Having a loose belt reduces the k, and the f, which in turn affects vibration compensation.
H2D monitors belt tension through this equation f = sqrt (k/m). During calibration, the motors will generate vibrations at various frequencies and look for the resonance, which happens when the input frequency is equal to the natural frequency. We call this operation frequency sweep, and it generates quite some noise with an increasing pitch.
When the H2D finds that the natural frequency has changed, it is time to tighten the belt. It is a semi-automatic process and can be done with a simple operation.
IMPORTANT: Power OFF the printer first.
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*The diagram illustrates tool head positioning; the hotend does not need to be detached.
After positioning, ensure the tool head and X-Axis alignment matches the picture below before proceeding.
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IMPORTANT: DO NOT overtighten the belt tensioning screws. Doing that can cause damage and will not provide better results. Simply tighten both screws like any other screws and don't over-torque them.
After the belt tensioning operation is completed, the resonant frequency identification needs to be recalibrated to record the new resonance characteristics of the equipment.
The H2D printer can be calibrated from the screen or Bambu Studio.
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