Motion and control
Why does one printer move its bed and the other doesn’t?
An Ender 3 and a Trideo Box inspire an engineering question: how many ways can you move a nozzle to the same point?
Video in preparation. You can explore all the content on this page right now.
Can you print while the part stays still?
Yes. What matters is the nozzle’s movement relative to the part. Different machines share that movement between different components.
01 / Three numbers for a point
X and Y locate a point in the plane of a layer. Z represents height. An instruction does not say ‘draw a finger’: it specifies coordinates. Before printing, homing establishes reference positions using sensors or endstops.
02 / Two ways to share the motion
In a typical bed slinger, the head moves in X and the bed in Y: the part travels with it. In CoreXY, two motors and their belts coordinate the head’s X and Y motion. The bed does not need to slide back and forth in that plane; Z motion depends on the design. The simulator is a general diagram, not a reproduction of a specific Trideo model.
03 / Mass, acceleration and choices
Accelerating a bed also accelerates the part. A tall part can vibrate and limit usable acceleration. CoreXY reduces some of that moving mass, in exchange for a more complex belt system. Rigidity, tuning and maintenance matter as much as the architecture’s name.
04 / Counting steps and controlling heat
Example: 200 steps per revolution × 16 microsteps ÷ 40 mm per revolution = 80 microsteps per millimetre. Each commanded microstep corresponds to 0.0125 mm; that does not guarantee the same accuracy in a part. Belts, loads and extrusion also matter. Temperature is controlled by reading a thermistor and adjusting heater power.
The same path. Two machines.
Change X and Y and watch the top view. The cross marks the nozzle’s relative position; the diagrams exaggerate movement.
Bed slinger
CoreXY
On a bed slinger, Y moves the part opposite to the nozzle’s relative motion. In CoreXY, the head moves.
Teaching model · Not results from filming.
Coordinates without a printer
Materials: graph paper, a pencil and another person.
- Mark an origin. Read out five (X, Y) pairs so the other person can draw a path without seeing your drawing.
- Repeat by moving the paper in Y and the pencil in X. Can you get the same shape?
- Compare the paths and discuss why you need to agree on the origin and units before starting.
Questions to keep you thinking.
Does CoreXY always print better?
No. Architecture changes the possibilities and trade-offs, but a well-calibrated machine of either type can make good parts.
Is a CoreXY bed completely stationary?
Not necessarily. CoreXY describes X and Y motion. Some designs move the bed in Z; others move the head assembly.
Should I put water on my printer to test it?
The activity uses paper. The filming demonstration requires closed, secured containers away from the nozzle and electronics, with supervision. Keep liquids away from operating machines.
What did you take away?
Three questions, no grades and no rush. Every answer comes with an explanation.
Answers explained
Which axis represents layer height?
Z. Z is the vertical coordinate in this system.
What does 0.0125 mm per microstep mean?
Nominal commanded movement. It is a theoretical motion resolution, without mechanical and process errors.
What does temperature control do?
Measure, compare and adjust the heater. The thermistor reading lets the controller correct power towards the target temperature.
Keep exploring
Content based on the Hands On Science script. Additional technical references: