Gridded Globe

This gridded globe is a challenging item to print. It is designed by MakerBot to show the quality of their printer and the advise was to print this in PLA.

The model is available at Thing:31688 and I've printed this in the default size resulting in a 125 m globe.

During printing a fair bit of stringing occurs. No wonder: the grid structure is round but how do you print a round structure using bridging ??? Another thing is that this model is not designed to be printable (without support). Looking at the STL model I noticed that there some parts that hang below the line or even small ilands that sit in the middle of the ocean, connected to nothing at all - even when printed with support, there is nothing keeping it a part of the model afterwards.

These parts do results in strings drooping from the nozzle.
Luckily the strings are easily removed.

Another picture taking during printing.
The overhang is more than 45° and it prints very good in PLA with cooling.


A detail of a section that hangs below the line. Printed without support so there is nothing to keep it there during printing. Except of course the little pieces of string that droop down when the first layer of this section is being printed.
It looks like these few extrusions are enough to keep these parts fairly well in place.

Some frayed ends at the bottom part of Australia, Papua New Guinea looks good but New Zealand is almost gone.

If you look closely you can also see that the grid at the bottom is a bit rough. The overhang is too much to be printed perfectly but I am still amazed by the quality.