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Slewentogzz

Extruder time offset

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I have an idea to make the filament extrude more evenly. When you print fast, but with low acceleration (to reduce ringing) the corners of the model get "squished out" as the pressure in the hot-end doesn't equalize quickly enough. I'm sure some of you are familiar with this:

file-NjVxvkclZQ.jpg

To prevent this I'm suggesting a new feature, I don't know what it should be called, but something along "extrusion time offset". The extruder would have a time offset of e.g. -0.2 seconds, which means that the extruder extrudes 0.2 seconds before it should've extruded if it was setup normally. So the extruder's instructions is offset by -0.2 s from the instructions given to the rest of the printer.

So when pressure has built up in the hot-end, it has time to equalize by the time the printer changes direction (e.g. a corner), as the extruder extrudes more slowly earlier. And it also starts extruding earlier when the printer is accelerating up to speed.

If you tune this "extrusion time offset" I'm quite sure that you can make wonders to corners on prints.

Please let me know what you think, I have very little knowledge of programming, so I don't know if this is possible.

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Have you tried increasing Jerk (while leaving Acceleration alone) and does that improve the corners?

That usually helps on my printers, but I don't know what type of printer you have.

Your belts might need re-tensioning as well to help reducing ringing.

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Have you tried increasing Jerk (while leaving Acceleration alone) and does that improve the corners?

That usually helps on my printers, but I don't know what type of printer you have.

Your belts might need re-tensioning as well to help reducing ringing.

Yes, I have a quite high jerk (20 mm/s if I remember correctly). Any higher makes terrible ringing patterns, especially along y-axis on tall objects (i3-style printer).

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