1. a three-dimensional image formed by the interference of light beams from a laser or other coherent light source. 2. a photograph of an interference pattern which, when suitably illuminated, produces a three-dimensional image.
UCC Machine History
- Hologram was bought with a UWA Guild special projects grant in semester 2 of 2015 [citation needed], and arriving with one sample 80m filament reel. Utilisation was initially low until a tech talk near the conclusion of semester 1 2016 which resulted in adequate interest to consume the sample reel and move onto the a 400m purchased reel which committee decided would be available for free to encourage utilisation.
Current Machine Tasks
- Printing things into the 3rd dimension
- Producing tuna can support infrastructure for dispense
- Causing every single 2nd year student present in the room to ask "What are you 3D Printing?" at least once every 3 hours
Current Software Configuration
Hologram's hardware receives its operating gcode from devices linked by microUSB. So far Hologram has successfully implement gcode from the free slicer software packages Cura and Repetier. These programs accept .stl files and parse them into a set of instructions for the print head and attendant motors.
Current hardware configuration
- Hologram was a pre-assembled Printrbot Play with an all metal hot-end. The original hot-end was annihilated in a horrible failure cascade resulting from letting filament run past the extrusion gear. DON'T DO THIS.
Current plans are to purchase and install an Ubis 13S Hot-end as a replacement since the original is no longer available for purchase. This is arguably better than Hologram deserves.
Future Plans for the Machine
- Ideally, when Hologram becomes the popular kid in the classroom, utilisation will be adequate to justify the purchase of an additional 3D Printer with none of Holograms attendant flaws.
Operating the Machine
- Successful production of 3D objects with Hologram is reliant on an understanding of its capabilities.
Acquiring the Digital Model
The first step is to acquire a .stl formatted file of the object you wish to print. This can commonly be produced in 3D modelling software such as Blender, or acquired directly from online sharing sites such as Thingiverse.
Inspecting the Digital Model
- There are a great many structural features that can cause a model to fail unless they are compensated for. You should always use either your 3D modelling software, or your slicer software, to inspect the model for the following problematic features:
- The model's "base" is not actually level. A surprisingly common issue with many models from databases. If you have an array of parts to be printed, they often will be only approximately level. If you do not level them to within .1mm using 3d modelling, your slicer will not correct the imbalance and any parts that have a base above the base z-layer of the model will turn into spaghetti.
- The model has significant overhangs. Hologram ONLY prints from the bottom z-layer to the top. Anything with no physical support leading towards the base when it prints will turn into spaghetti, and if the 'lean' away from the vertical exceeds 45 degrees for more than 2mm, the print will begin degrading in quality in that region. Manually add supports, or use your slicer's automatic supports, to compensate for this.
- The model has many small objects intersecting a large object, where the small objects are weight bearing. Some slicers do strange things with intersecting objects and their internal support grid. It is not always necessary to correct this fault, but stay vigilant. This issue tends to result in the model snapping apart in the middle of a print as weight is added to the malformed support structure at the base of the small objects.
Acquiring the Software
Cura and Repetier are both easily acquired. I believe that Cura is the easiest to use but requires some customisation to utilise more in-depth printing options. The most version of Cura, 2.1.3, does not support Hologram's hardware. It must be operated by Cura 15.04.6 or earlier. Ensure that immediately post-install you connect your device to Hologram, run your slicer, and are capable of setting your slicer to operate a "Printrbot" -> "Printrbot Play".
Setting up a Print
- Keep in mind that removing the PLA plastic Hologram is equipped with directly from its metal bed is a nightmare, so before each print ensure that the green tape associated with Hologram has been laid across the base. This keeps the print bed clean and makes removing finished models much easier.
The default settings on your slicer of choice FOR A PRINTRBOT PLAY, are usually adequate. However, there are some features relatively likely to require modification.
Print Speed
- Does not linearly reduce the time you will be waiting for your print to conclude, but increasing print speed still always makes for a faster print. However, there is also a small inaccuracy introduced at high speed. For printing fine details like on models for Unigames, or extremely small technical components, 20-30mm/s print speed is appropriate. For larger (approaching 10cm) objects such as props that nonetheless have some critical dimensions, 75mm/s is appropriate.
Print Temperature
- Print Temperature is a strange and esoteric variable. Your slicer will recommend you 210C, but Hologram seems to operate best at between 207C and 209C. Generally, a slower, fine detail print should be done at 207C. However, Hologram's performance seems to change at different ambient temperatures and compensating for this with Print Head Temperature has yet to be explored.
Fill Density
- The greater the Fill Density, the more internal structural support is added, and thus the greater the time taken for a print, but the greater the structural integrity. For aesthetic prints such as models the default 20% is perfectly adequate. For objects likely to bear significant weight, a value around 40% - 60% is probably more appropriate.
Platform Adhesion & Support Type
- These features can add automatically generated structures to your print to assist their success.
Platform adhesion type "Brim" can be good if you are experiencing difficulties getting the first layer of your print to attach, but is probably more trouble than it's worth if you have critical details right at the first z - layer.
Supports can be added automatically to your print if you see overhangs and you are lazy. The automatic supports can be removed easily, leave only a small amount of residue on the model, but add a considerable amount to print time.
Flow and Retraction
- These are framed as advanced features in most slicers, that cause the filament to be pulled back into the head between printing features, and compensate for the free flow of molten filament through the print head. They are worth considering for Hologram because it leaks molten filament straight through the print head for basically as long as the head remains hot and needs to be cleaned perpetually PRIOR to the commencement of a print. Intelligent application of these features can minimise the amount of mess made during a print. Unintelligent application can murder the hot end a second time, costing the club $100 a second time.
Heated Bed Emulation
- Hologram, unlike 3D Printers that cost significant money, lacks a heated bed, meaning that printing anything with a small surface area of contact with the print bed can result in print failure (IE anything lacking a large 'base'). While printing a brim is a great way to address this for most models, for arrays of small parts, this adds way too much post processing. By setting the SMD Rework station to 360C and gently flambeing the metal bed to an even heat while avoiding other parts, right before the print head begins its alignment, you can assist the first z - layer in adhering to the base with only a small amount of flaring. An actual heated bed would go to about 204C, but I have observed improved outcomes with temperatures that are still safe to touch for a short time, heating the bed to approximately 60C - 70C prior to print.
Troubleshooting your Finished Print
- Unless you are 3D Printing a brick, you will see more unsuccessful prints than successful ones. Here are some common issues:
- Missing components: Pretty much always the result of a lack of support on the component. This may be because it is incorrectly aligned with the base in the 3D model and has turned into spaghetti, or it may be that its supports collapsed mid print because they were too small or their base was inadequate, and the rest of it turned into spaghetti.
- Horizontal crevasses and ridges: A result of z-layer misalignment. This can happen for a variety of reasons. It presents as either very thin slivers for thick prints, or drawn out 'wave' patterns over several layers for fine prints. In theory a common one is if the motor belts are misaligned or dirty, but in practice with Hologram it is nearly always due to the filament not feeding into the print head cleanly. Sometimes simply re-attempting the print with no change will fix this, but ensure that the filament can be easily pulled from the reel smoothly and it spins freely and evenly. Consider pulling an amount of filament equal to slightly more than what you need into a smaller loop to hang closer to the machine so that there is less friction to contend with as the print head feeds.
- "Spiderwebs" everywhere: This is pretty much inevitable for any print containing a large number of thin, fine features. In some ways this is actually good for you model as it provides extra support during the print. You'll need to remove them with a file but is that really so bad?
Thanks to:
[EJK], [AMS], [BG3], for the initiative to buy the printer [AMS], [TBB] for running the S1 2016 Tech Talk [LDT] for driving utilisation and constructing this wiki page