LulzBot Mini 3D Printer Review

We have received a LulzBot Mini 3D Printer for review from our friends at Aleph Objects – an open hardware company in Loveland, Colorado. We respect Aleph Objects as a company true to the open source ethic – while developing one of the best 3D printers on the market.

We are not the only reviewers with a high and positive impression. LulzBot TAZ 5 has just been listed in April by as the first of the top 3D printers on the market. Just this week, the LulzBot Mini has been named the Best Intermediate 3D Printer by Tom’s Guide. Other distinctions include PC Mag Editor’s Choice this February, a great review in Computerworld in January – and solely 5 star reviews on Amazon.

For OSE, the advantages are that the LulzBot Mini is open source. Because it is open source, one can build the printer from its design files, available for free download (link?). Last year, we collaborated with Aleph Objects and ran a workshop where we built 12 of the older versions of LulzBot – KITTAZ – from a kit provided by Aleph Objects.

Now the moment of truth. Before starting the first LulzBot Mini print, I asked myself – “On this printer with auto bed leveling – will I finally enjoy this as my first experience where I simply click a button on the computer, and a complete print job will come out the other side without me making any sort of adjustment or tweak?” Upon starting a print – the print head wipes itself automatically against a cleaning pad. Then – the machine performs automatic bed leveling. And I printed the Rocktopus sample print just like this:

My hopes were redeemed. It just works. I pay a lot of attention to auto bed leveling because leveling is a process which gave us trouble with all other printers last year, including the earlier LulzBot TAZ. Things would be going fine on a given 3D printer, and then at some random point, the print would fail, typically due to issues with bed leveling. The situation is that if the height of the print head is not at the exact required level for the first printing layer, then the nozzle can clog if the head is too low, or the first layer won’t stick to the bed if the head is too high. This requires the user to watch the start, and abort and calibrate the height by moving the print head across the bed while measuring the height off the bed with a sheet of paper. To adjust the print bed, one manipulates adjustment screws on the base. While this process is easy and quick for experienced users, we found out with 18 interns over the entire summer last year – that this was a significant challenge. Out of our 4 3D printers, we had a max of 2 running at one time and typically only 1 – due in significant part to issues related to bed leveling. Typically, people would just take the easy way out and rely on the working printers without fixing the leveling. Experienced users may laugh at this – but that was our reality when a significant number of people without prior 3D printing experience are let loose on a 3D printer cluster with little oversight. I personally feel that the bed leveling issue is the single item that keeps 3D printers in the hacker world, not in the popular world.

This is all history with the LulzBot Mini because of its auto bed leveling capacity. The print head touches the 4 corners of the print bed upon startup – closing an electrical connection as the means of detection – where depending on these 4 touch-off points – the height of the head is adjusted by the software. To us, that is a significant and critical improvement for making 3D printing accessible to anyone – as something that Just Works.

This is a long way from the early days of 3D printing. It seems to me that the bed leveling function is the single most important improvement that can take a 3D printer from the realm of hackers to the realm of It Just Works. Surprisingly, the 2 leading 3D printers, Makerbot and Ultimaker, do not appear to provide auto bed leveling. Thus, LulzBot appearst to be leading the way with auto bed leveling in the overall world of 3D printers. LulzBot is the first consumer 3D printer that is both open source AND has bed leveling.

Is auto bed leveling really necessary? It’s a controversial topic – and the answer depends on who you ask. See an interesting thread on Reddit. To an experienced user, one minute of bed leveling every so often on a multi-hour print job is not much to ask for. To OSE, auto bed level is absolutely indispensable when you have multiple people using the same 3D printer, especially when the 3D printer users haven’t been trained properly. It’s the difference between having a print created and not having one – or the difference between a machine that is consumer grade vs. hacker grade. I personally do not look forward to whenever I have to level a print bed. How many thousands, if not millions, of hours will have been spent on bed leveling for the 200,000, and growing, 3D printers that ship yearly, if they do not feature auto bed leveling? Auto level should be just a standard feature, because it Just Works.

For those of you steeped in open source lore, you may find it interesting that Makerbot is not currently on some of the lists of top 3D printers. Makerbot, formerly open source, is the goliath that currently holds the largest market share in the consumer 3D printer market. Makerbot sold out to Stratasys in 2013 for $403 million, spurring criticism from the open source community as Makerbot turned from open source to proprietary. One of Makerbot’s founders, Zach Hoeken, shared his insights regarding the negative effect of open source enclosure by Makerbot – formerly the world’s largest open source hardware company:

“Yes, OSHW [Open Source HardWare] is viable as a business model, look at how successful MakerBot is.” If they close those doors, then it would give people who would say OSHW is not sustainable ammunition for their arguments. It would also discourage new OSHW companies from forming.”

My observations indicate that the open source chilling effect of Makerbot’s enclosure is real and undeniable, as Zach Hoeken predicted. I have had several conversations with various entrepreneurs where I was suprised by their generally-assumed-as-true position that Open Source Cannot Provide a Viable Business Model. That is a short-sighted blanket statement. It appears to be influenced by the case of Makerbot. And this negative notion of OSHW is ubiquitous in the mainstream world – if one can read the writing on the wall.

LulzBot is fully open source, and in fact, recipient of the Respects Your Freedom hardware product certification from the Free Software Foundation. You can download official release Mini files here. You ca also download the ongoing development work here. The source of the Cura control software is here.

Growing rapidly, LulzBot is in a good position to increase the open source share of the market drastically. When I visited LulzBot in early 2014, they just got a new factory space. They currently have 75 employees. OSE looks forward to further collaboration with Jeff Moe, LulzBot founder and CEO – as he supports the open source community and is interested in open hardware in general.

It appears to me that the automatic bed leveling function of the LulzBot Mini sets it apart from the competition. It makes our life much easier in terms of eliminating setup time before any print.

Is setup time required when switching spools of filament? To switch a spool, just heat up the nozzle, and insert the new filament into the extruder. Switching to PLA plastic from the initial HIPS plastic test run, there was no issue. I tried a model tube shape to test the stability of printing tall, columnar objects – such as scale model tubing like for our open source tractor. There was no visible wobble in the print at the very top:


The print at rough setting looks like this:


Note that this was done at the fastest, lowest quality setting – we are just interested in scale models, where we are not looking for part strength. And here is a result of a larger batch:


And comments about the print:

The LulzBot Mini can print with many different materials. An extruder for printing with rubber is currently available for the LulzBot TAZ, and is in development for the LulzBot Mini. We plan on 3D printing this extruder once the open source design becomes available from LulzBot. The development version of this extruder – the Mini Flexystruder – can be downloaded here.

For OSE purposes, we are particularly interested in the following applications of 3D printing:

1. Plumbing fittings – custom, low pressure, water tight connections for irrigation ponds and aquaponics.
2. High pressure tractor hydraulics – using rubber printing for high pressure seals, gaskets, and o-rings for hydraulic cylinders, valves, and motors. This blends precision manufacturing with 3D printing for high pressure applications.
3. Scale modeling – prototyping of the Tractor Construction Set and other machines of the Global Village Construction Set
4. Agriculture – printing useful tools such as the grafting tool – which I discussed in a blog post from 2009 when 3D printing was just getting off the ground.

Now what are the disadvantages of the LulzBot Mini? I don’t like that the print bed moves, as this can cause wobble in certain tall objects that are being printed. I have not seen this be be an issue on the Mini yet, but it probably means that the structure being printed can wobble in certain cases, and possibly come off the print platform. This may be true for very thin and tall structures, or for top-heavy structures – where extra support or slower print speed would have to be used to prevent any issues. I’ve seen this issue in the LulzBot TAZ. The only other issue may be that the USB print connection requires one to have a computer connected to the 3D printer for the duration of a print, as opposed to using a memory card without a computer connection. This means that one can’t take their computer with them if they want to leave when a long print job is running.

As far as the sofware, Cura is simple and it works well. I was pleasantly surprised at the bonus visual effect upon opening up of print files. One sofware glitch was that after installing Cura on my Ubuntu 12.04, the computer did not detect the printer through the USB port. Turning the computer on and off solved the connection issue – it appears that the computer must be reset after the initial software install. I then heated up the nozzle via Cura to remove the filament piece that the Mini ships with, then inserted new filament. I began the first print as in the video. The printer brushed the nozzle to clean it, and then the auto leveling took a few second. Then the print started. Walking away from the computer, I had to disable power saving so the computer would not go to sleep.

All in all, I am looking forward to finally having a turnkey 3D office printer for scale modeling – free from any demand of bed leveling. This allows us to run various test-driven design proofs-of-fabrication. It is useful to examine not only how 3D printed scale models of machines will look in physical shape – but also – we can test assembly and bolting sequences of scale models fully before doing so in real life. Before any multi-ton heavy machine is built, there is no reason why a complete scaled-down prototype cannot be not done prior to the build. This seems obvious that this would be a wise thing to do, but we are just now evolving our development techniques to the point where scale model prototyping becomes fully integrated into our workflows as a normal operating procedure.


  1. Paweł

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  2. Tom

    For this purpose :
    “High pressure tractor hydraulics – using rubber printing for high pressure seals, gaskets, and o-rings for hydraulic cylinders, valves, and motors. This blends precision manufacturing with 3D printing for high pressure applications.”

    Are there filaments available at the moment? TPU,TPE,some other flexible one? Or these are not resilient enough for high pressure seals (oil/grease resistance,Shore 60-90 availability etc.) ?!