3D Print of the Month – February 2014
Time is really flying. It is already end of February and I haven’t posted the 3D print of the month yet so high time to get this done! This month I have chosen an item that is literally hands-on and very practical.
I didn’t have to search long for finding the right object to print for this month: recently, I have been traveling with the Ultimaker printer quite a bit. Carrying the Ultimaker is not a problem since it is not very heavy. However, you tend to lift it with the upper part of the housing and I found that I often inadvertently grabbed either one of the axes or one of the timing belts. This is less than ideal since these parts directly affect the precision of the 3D prints and you don’t want them to be bend or damaged.
So, what I needed was a handle making it easy to lift and carry the Ultimaker, without the danger of damaging any of the mechanical parts.
Sourcing the 3D Model
I knew I had seen such handles on Thingiverse before, so I just searched for ‘Ultimaker handle’ and sure enough it brought up two handles suited for my needs: the Ultimaker handle (thing: 22819) and the Ultimaker heavy-duty handle (thing: 80040).
I settled for the Ultimaker heavy-duty handle which is the sturdier version of the two handles.
Preparing the 3D Print
The Ultimaker heavy-duty handle comes in a single *.stl file which I loaded straight into Cura. The only modification I needed to do was to rotate the handle 45 degrees to make it fit diagonally onto the build platform. Cura estimated the print time at 2h 38min.
Executing the 3D Print
I decided to print the handle using translucent PLA. I recently received a sample spool from a Chinese manufacturer such that I also wanted to test the quality of this filament. Once I had swapped the spool, I launched the print.
As usual, I watched the Ultimaker closely while it was laying down the first few lines of the print. I noticed straight away that the material flow from the nozzle was not continuous enough. I tweaked the nozzle temperature from 210°C to 230°C which resulted in a better material flow, solving the issue.
Once I was satisfied that the material flow was good and that the first few layers of the print were securely in place, I let the Ultimaker do its job. As the print geometry was not very complicated, I didn’t expect any major issues. The only parts of the print that I ended up watching more closely were the screw openings were the printer needed to master an overhang, albeit a fairly small one. At a print speed of 75mm/s the Ultimaker mastered these overhangs without any issues.
The 3D print was completed after three hours and I managed to peel it off the build platform without any issues. It needed almost no further processing, I just removed a few loose strands of PLA and the handle was ready to be installed on the Ultimaker.
3D print specs:
Filament: 6.86m/54.28 g of PLA filament
Print time: 2h 38min predicted / 3h 01min actual
Temperature: 230°C (adjusted from 210°C)
Print speed: 50mm/s
Infill speed: 75mm/s
Lessons Learned from January 2014 3D Print of the Month
Here are a few observations from printing the Ultimaker handle:
- Warping: the only thing that did go somewhat wrong on this 3D print was that once again some warping occurred. As you can see from the pictures, the warping was limited to one end of the handle though it was pretty sizable here: the thickness of this end of the handle is 16.0 mm on the lowest point compared to 19.5 mm on the side of the handle that printed fine. So the warp led to a shrinkage of 3.5 mm, not negligible.The good news is that the use of the handle is not adversely affected. The warp did not affect the positioning of the screw openings which are critical to install the handle on the Ultimaker. However, given the recurring warping issues, I will investigate warping and shrinkage in a more detailed post soon.
- Overhang: the Ultimaker mastered the overhang of the screw openings well. However, looking at the finished print one can see that the screw openings are not perfectly round since some of the PLA strands slightly sagged at the top end. This could probably be avoided by tuning the print speed specifically for this section of the print. Still, the screws fit well so this did not affect the usability of the handle.
- Translucent PLA: it turns out that the China-made PLA did a decent job for this print. The only difference to other PLA that I noticed is the fact that it required a higher extrusion temperature. Once this was adjusted it printed fine. Not a bad start for this material, but I’ll still put it to some more rigorous tests before giving my final verdict.
Resources mentioned in this blog post:
As usual, feel free to share your comments below. Any questions on the 3D print of February 2014 or suggestions for a future 3D print of the month are welcome!