Infill Uses Two Axis

Hey, New to the forum and 3D printing so this may well be a simple/idiotic question.

Ive been watching my printer for a while now, the novelty still hast worn off . Would someone be kind enough to explain why the infill lines [square infill type] are at 45* and -45 to the x-plain and not straight up and down [0* and 90*]. At the moment my printer moves both the x and y axis to create each infill line, I believe it would be faster if it moved just one axis for each infill line, but I'm sure there will be a reason it is printing in this way.



Printer: Persia i3 [Plywood frame, cheap ebay one].
Slicing: Cura 15.0

In the past ive been using a ultimaker 2 [at a Local FabLab] and decided to get my own budget printer.... The RepRap persia i3. It prints quite nice apart from a ribbing effect in the z direction.

Hope this is in the right section.

You can change the angle if you want to and see what happens. When you slice using slic3r go to print settings>infill>advanced, and set the infill angle to 0 degrees.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

The infill will print faster if you set it to print faster. Using one axis or two doesn't specifically make a difference to the speed here. In cura this is in the advanced tab under infill speed. If it's set to 0 it will print the same as the perimeter speed. I don't think that cura lets you change the angle of infill. Simplify lets you set whatever angle/angles you want for both infill and support.

Actually, it might be faster with diagonal infill depending on your firmware and configuration. If your jerks and accelerations are set per-axis (which is appropriate, but some firmwares might use the resultant vector sum), you will get more total jerk and acceleration using both axes, so the printer will spend more time at the set speed (or as close to it as practicable).

Thanks for the replies I appreciate it, I will try a few prints with the setting changed and see how it effects print time.

If I am understanding the theory correctly, by using two axis im printing the infill 1.4 times faster with the same motor speed Good to know.

Edited 1 time(s). Last edit at 05/14/2016 09:39AM by m.ratcliffe.

Quote
m.ratcliffe
Thanks for the replies I appreciate it, I will try a few prints with the setting changed and see how it effects print time.

If I am understanding the theory correctly, by using two axis im printing the infill 1.4 times faster with the same motor speed Good to know.

No, that is only correct if the axis were moving at their speed limits before you switched the angle. As I said above, using one axis or two in this case is NOT limiting your infill speed, only in the edge case that you were at the machines maximum speed in a single axis to start. Let's start with some basics, what speed do you have set in your slicer for perimeters? What speed do you have set for infill?

As far as I can tell, it is printing the infill at the same speed as the perimeter

Right, so if you want to increase the infill speed above the perimeter speed, change the "0" to something >50. Unless your printer can't move more than 50mm/s in a single axis changing the direction here will have very little impact. As suggested above, accell and jerk can play a role here, but at the speeds you are taking about the effect is pretty negligible.
Also keep in mind that a hot end performs smoothest when you aren't changing flow rates extremely. If you set your infill to say 100mm/s in your case the infill would be at a much higher flow rate than the perimeter. Constantly shifting back and forth changes the pressure in the hot end, and these changes can be seen in print quality. Application dependent of course, but something to keep in mind. Another useful feature to speed infill is the "print infill every "N" layers" function that simplify3d and I think a few other slicers have. If "N" is set to 2, it would print 2 perimeter layers and then one infill layer that is double thick. This lets you keep detail on the perimeter but faster on the infill. Simplify does have a few bugs in this feature, but it can save a huge amount of time.