Thanks Victor,
Your math is interesting. In order to reduce building times, it becomes necessary to reduce accuracy and increase speed. This requires modifications to the RepRap in terms of extruder filament size and larger diameter drive pulleys. It seems that the host's preferences settings like "extruder0_extrusionsize(mm)" and "AxisScale(steps/mm)" and "MaximumFeedrate(mm/minute)" would enable the current host software to control a larger RepRap.
Interesting thing about lowering accuracy is that it takes care of the sagging problem at the same time. I mean, as the machine size goes up and sagging increases, the extent of sagging becomes negligible compared to the filament size and the size of the object being made.
Just a thought....
Brew
