Go to the group assignment page
Weekly assignment: Test Printer → Design an object → Print object → Scan object → Print scanned object (optional)
On the 3D printer test model's page, I downloaded the design and noted the parameters it tests, such as:
Bellow is the 3D print test model:
The author also provides an image for reference when checking the print.
Now, this sub-class of the Print settings is infill. One can save a lot of time and money here. Someone once said they are both the same; frankly, I'd rather own the first than the second. The infill I have is 20%. I am not a cheapskate; I believe 20% is enough. After all, the ephemeral pieces this printer expels are rarely worth using all this corn. Ah, did I mention I am using PLA, a derivative of corn? Of course not; that's later in filaments... So, for now, believe me, 20% is enough for almost all prints. If you need to tow a truck, go crazy, use 100%. If, on the other hand, you want to make a delicate vase, 0% will leave you a hollow print.
In this subsection of Print settings, the famous Skirt and Brim, the savvy fabber can use Brim instead of the ridiculous and wasteful rafts done by those who won't take the time to level and calibrate their printers. By using a wide brim, you make sure your print won't detach from the bed. Brim basically consists of lines next to each other and attached to the print; it's great for a spiky model's base, or just corners that want to take off from the print bed, causing "warping". The skirt is used to kind of clean one's noose—I mean nozzle, yes, the printer nozzle, the part that the filament comes out of. This setting will extrude a line around the model to be printed, especially useful when filament promiscuity is the case, so when changing colors or filament types, be sure to either extrude in the air or add some skirt before your print.
The subclass of Support material I leave for the people who won't challenge their machines for the ones who don't care to calibrate and level.
With Support material, you use this for overhangs. Support builds under your model in places where the negative slope is too steep, in order to prevent a real bird's nest by free-forming under your nose—I mean nozzle.
Raft... how I hate rafts! I don't even want to talk about rafts. I wonder how much popcorn has been erased from the universe by the usage of rafts! Well, like the name implies, no one wants to be on, or use, a raft. It's for emergencies and should be kept only for that. It creates a waste of material that will poorly compensate for the lack of leveling; it's for the lazy, but in the end, promotes more work, as the underside of the print will never be as smooth as the part printed directly on glass. Support also does that. Try printing with support and then spend the next hours post-processing your prints—super fun stuff.
The class of filament settings deserves not much time as they are straightforward. If your filament supplier cares about you, they will give you the temperature at which to print on a label on the sides of the box or spool. The diameter is, and has always been with me, 1.75mm. The thinner diameter is easier to push than 3mm, the other standard in filament thickness. After all, we are pushing filament through a nozzle with a 0.4 mm diameter; that's thin, so choosing a printer that takes a thin filament is better!
Here in printer settings, we find nozzle size. I use 0.4 mm. Next, my preferred setting in these tests—well, practically the only one I messed with—is "retraction".
As the designer, engineer, and technician of my printers, there's little that I haven't tried before.
The retraction, yes, the retraction, will depend on many factors. Too much retraction, and the filament can get stuck in the nozzle, guaranteeing one a lot of fun fixing/disassembling a nozzle where the filament froze in higher levels. It's always fun for geeks like me to fix that, NOT! Too little retraction, and you will have spider webs all around your towers. So, this is a setting that needs to be tested and tested, until, like many other settings, you do trial and error until mastered to what resembles perfection, if that even exists in FDM, of course.
Click here for the process of slicing and creating the file with the g-code to print.
Parameter | Results | ||
---|---|---|---|
Mini | Delta | ||
1 | Nut, Size M4 Nut should fit perfectly | Yes | No |
2 | Wave, rounded print | Yes | Yes |
3 | Star, Sharp Edges | Yes | Yes |
4 | Name, Complex Shapes | Yes | Yes |
5 | Holes, Size 3, 4, 5 mm | 2.9, 3.9, 4.9 | 3, 4, 5 mm oval |
6 | minimal Distance: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 mm | 0.1mm not good | 0.1, 0.2, 0.3 not good scale wrong 6.5mm instead of 7mm |
7 | Z height: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1 mm | 0.1mm printed with 0.2 and 1.1 with 1 | Yes |
8 | Wall Thickness: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 mm | didn't print 0.1, 0.2 next walls printed as 0.5 until last as 1mm | Yes |
9 | Bridge Print: 2, 4, 8, 16 mm | Printed as 2.85, 3.9, 7.9, 15.8 | Yes |
10 | Sphere, Rounded Print 4.8mm height | 5.1 | Yes |
11 | Sphere Mix, 7 mm height | 7.15 | Yes |
12 | pyramid, 7 mm height | 6.95 | Yes |
13 | Overhang: 25, 30, 35, 40, 45, 50, 55, 60, 65, 70° | Yes | Yes |
14 | Warp, does it bend? | no | Yes |
15 | 3D Print Font, optimized for 3D printing | Yes | Yes |
16 | Surface, Flatness | a bit rough | Yes |
17 | Size, 100 x 100mm x 23.83 (10mm width) | 99.45 x 99.8 x 23.2 (10.2 with) | Yes |
18 | Spike, minimum Layer Time, 21 mm height from Bottom (include Baseplate) | 15mm | Yes |
19 | Hole in Wall, 4 mm diameter, check for proper print | Yes | Yes |
20 | Raft Test, raft should be just under the model | didn't test | Yes |
21 | Retract Travel, check retract settings for longer travel | almost no oozing | Yes |
Conclusion | For an FDM printer, I believe the result is very good. The size differences are probably due to PLA shrinkage. |
This design is either too hard or even impossible to do with subtractive techniques due to its shape and details, which are inaccessible to a 2-axis CNC or even a 3-axis one.
The result:
The G-code generated can be downloaded with the link above, but I extracted the beginning of it here in order to show a few of its statistics:
; generated by Slic3r 1.3.1-dev on 2020-05-31 at 20:04:21
; external perimeters extrusion width = 0.44mm (3.38mm^3/s)
; perimeters extrusion width = 0.48mm (7.54mm^3/s)
; infill extrusion width = 0.48mm (10.05mm^3/s)
; solid infill extrusion width = 0.48mm (2.51mm^3/s)
; top infill extrusion width = 0.48mm (1.88mm^3/s)
; support material extrusion width = 0.44mm (6.76mm^3/s)