Visualization of step differences that occur with delta printers.

3D Printing
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Visualization of step differences that occur with delta printers. Notice that towards the outer edges, you gain resolution because it takes more steps in order to move the nozzle the same distance. Towards the middle, you have less resolution due to increased travel per step.

None of this is too terrible, most people won’t even notice it. But it is there and you’ll hear some of the more experienced among us tout it as a downside to delta-based 3D printers.
https://lh3.googleusercontent.com/-1p6cBfgiamQ/UI0gqJ1tioI/AAAAAAAAAKw/10McbTnzDco/s1600/resolution.jpg

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Science + Math is sooooo much better than opinion :wink:

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Also notice two other things:

While the resolution on of each of the three arms increases when the effector is far from that tower, the resolution of an arm decreases as the effector gets close to its tower. This affects resolution in the radial direction (distance from center) as well as Z axis accuracy.

Also notice that when the resolution of one axis increases dramatically (approaching infinity) near the far extreme, the step rate has to increase to maintain speed. By my quick and dirty calculations, this should result in measurable, real-world increases in print time when printing radial features near the limits of the platform.

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Wait, do you actually set up a Delta to have an arm all the way horizontal when at its extreme position? Wouldn’t such a position allow the platform to wobble/tilt perpendicular to the arm’s center axis?

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@Thomas_Sanladerer , you won’t typically run into that kind of situation. It depends on arm length. If you want to keep the step rate more even, then you can have longer arms, but the tradeoff is a taller machine.

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Also, if you make the arms long enough to keep the range of motion out of the step-rate-is-too-high range, it spends more time in the resolution-is-too-low range.