Curve resolution in Marlin or firmware generally

Hey Folks,

I'm new on the forum but I've had a printer for around 8 months now. I have a very smooth, precise and solid printer, together with my 0.9 degree motors and microstepping I have a X-Y positioning precision of 12.5 microns and a Z precision of 4 microns.

However I believe the real limitation of my prints on curves in the X-Y plane is simply G-code or firmware limitations. I can see and feel segments in arcs, I believe its related to the ability of the Arduino to handle enough floating point math real time?

Is there any way around this? be nice to get really smooth X-Y features when they are curved. Oh and an EDIT, I forgot to mention that I use Cura for generating my Gcode. Would switching to something else work better?

Thanks!

Chris

P.S. Incidentally my prints are very good, I'm using an E3D head with 0.3mm Makerbot clone nozzle.

Edited 1 time(s). Last edit at 12/09/2014 07:01PM by bart_dood.

All current 3D cad packages convert curves to a curve aproximations made up of a number of line segments when they export to STL. As STL has no concept of a curve.

Reprap firmware itself supports the arc function fine.

There is just no way to get from your model to gcode with arc commands via STL.

Some slicers do try an put arcs back in... but I dont know how suscessful this is. (or the details)

Basicaly look at your stl model in something like meshlab, are the curves as nice as you want them? No, go back to the cad and increase the line segments.

Failing that you going to have to write a whole new slicer that converts directly from your cad pacage to gcode