Thursday, 7 June 2012

Half a Ball of Stars - Support structures #30DoC day 6

For Day 6 of  30 days of creativity ( #30DoC ) I'm having a rest from designing things, but I wanted to give my printer a challenging print while I worked.

A few weeks ago I did a quick test print of the Ball of Stars Created by @Dizingof
I used basic support structure and low-grade PLA just to test it out.

I have been meaning to print another one, much bigger and with full support structure. Today I set it off to print while I worked. It would have been a 17+ hour print, but 9 hours into it, at about half way it shifted on the Y axis, probably due to the head catching on the massive structure with the rather high acceleration settings I use on MendelMax.

Some of the support removed.

You can see that about 40% into the build the Y axis shifted, so when I came home I stopped the print.

Before removing support - This is what it looked like after 9 hours of printing (the half a ball of stars is inside there somewhere!)

This was my first test print a few weeks back, I didn't clean all the support structure off, and it had some unsupported areas, this was sliced with Skeinforge V46 using external support structure at >60 degrees overhang giving me some sections that sagged when they printed in free space.

For the new print today, I made it 150mm wide and enabled support everywhere, as you can see from the above Visual Gcode (Repetier Host) it was a real monster! Skeinforge had to slice for almost 2 hours to output the Gcode for it.

In hindsight a little too ambitious and I should have slowed down the travel moves and enabled Z Lift (Hop) I think it would have printed OK if I had done that.

Doing the same model in Slic3r with support enabled only gives a support column in the centre of the model, so I could not use Slic3r for this print unfortunately, a real shame as it slices in just 8 mins.

It is fun watching these things print.

And it used a fair bit of PLA.

Removal of the support structure is quite easy, but takes a little time.

It needs a little more support removed, but I'm quite happy with how it came out, and it would have looked really good as a complete model and not for the Y Axis Shift.

My proposed new settings for a future print attempt -
I have sliced it again and this time enabled Z lift (Hop) and used Exterior Only support with a 45 Degree minimum support angle, this should give me some support on almost everything, but not cover the entire model.
These are my support settings shown above, if anyone can give any advice to improve these, do get in touch or leave a comment, I hardly ever use support, so could do with any pointers you have.

It still looks like a lot of material, but compare the Gcode image below with the failed print above -

Fingers crossed, it should print well next time, and have a lot less support material to remove.

I'll give it another try soon and give an update.

Thanks for reading,