Pyramid Print – Testing for strings

Posted on July 3, 2011

I saw that this pyramid (made by 3dprinterbot on thingiverse) was a good way to calibrate the stringing which occurs when the print head moves from one object across mid air to another.  Retraction is what its called and its under the Dimension Menu in Skeinforge. (Skeinforge->Carve->Dimension->’Retraction Distance’) It is set for 25mm and the extruder retraction speed is set for 50mm/s. ‘Restart extra distance’ is set as ‘0’

I will post up more trials with the retraction speed increased more.  Below are some photos of the stringing, and the object after cleaning up the strings.  Should note that cleaning up didnt take too long.  I only had to break the strings off with my fingers and a small screw driver to get to the corners. This huxley has come a long way and I must congratulate the machine for keeping together and not breaking down :).

Another item which I changed from the last time I ran the machine was Feed rate under speed (Skeinforge->Carve->Speed->Feedrate). It was set at 11, I changed it to 12. I think I will also increase this and the travel feed rate which is under the same menu.  The travel feed rate is how fast the printer goes while not printing, so that would be the mid air between the pyramid pillars.

Temperature is another value I will change. Im thinking of reducing it to 225C instead of 230C, maybe this will help make the plastic more controllable.  Just don’t want the temp too low because that will cause plastic to not flow causing pressure on the whole system.

Ok enough blabbing, pictures speak 1000 words.

before string cleanup

after cleanup