2021-03-29
md
First 3D Prints with an ANYCUBIC Mega Zero

After wistfully looking at 3D printers for the last three or four years, I purchased a ANYCUBIC Mega Zero a few months ago. Until then, I had been eyeing the Creality Ender-3 which is a popular choice for beginners. However the almost $400 CDN (when adding shipping charges) price tag looked a bit steep for what I feared might be just a toy. Furthermore, there are so many blogs and videos about "properly setting up" the Ender-3 and others on "improving" the printer, that it seemed like 3D printing would require a major investment in time before getting any kind of proficiency. On a couple of occasions, I almost went ahead with a purchase, only to be confused by the many models on sale, with some vendors claiming to be selling an improved version, others claiming to be the genuine Creality and so on.

In September 2020, I made a snap decision to get the Mega Zero almost immediately after seeing YouTube videos about it. Most influential was the Review of the $150 Anycubic Mega Zero 3D Printer by Ben Heck whose opinion I have valued over the years. The clincher was that the printer was available in Canada at the stated price (taking into consideration the exchange rate of course) with reasonable shipping charges. The review made me believe that "building" the printer would not be difficult and decent print results could be expected without too much fiddling. It was also clear that there was no heated bed which would impose a limit on the types of filament that could be used. However I felt more comfortable spending $230 CDN to get my toe into the water. I also decided that I would give myself a year in which to experiment and familiarize myself with the technology and with 3D cad programs. After that period, if 3D printing proved to be something worth pursuing, then it would always be possible to move up to a more advanced printer if the need was there.

It has only been six months, so why write a post about this printer now? There are a number of factors at play. Perhaps the most important one is that the Mega Zero has been supplanted by the Mega Zero 2.0. Currently Americans cannot get the 2.0 but they have ready access to the original Mega Zero at a very low price of $119 US + shipping charges. Indeed, I think only buyers in the USA can still get the version 1 of the product. Since this offer may very well be limited to current stock, I thought that if this post could be of any use to any one contemplating the original version of the Mega Zero, it had to be made available as soon as possible. There is another reason which will be exposed at the end.

Everyone will have different reasons for getting a 3D printer. I am a digital electronics enthusiast with absolutely no experience with 3D printer and no interest in printing bobbles, sci-fi paraphernalia, toys and so on. The interest for me was in making project case and other utilitarian objects. So after printing the sample owl, I had just enough of the small amount of filament included with the printer to print a prototype of the face plate meant to hold an LCD display for a small project that I have had on the books for many months.

Then there was a long interlude while waiting for some filament to arrive. Also a sturdy base had to be build because leaving the printer on the floor was just not practical. After finally getting a hold of a couple of sheets of MDF large enough to accomodate the printer and then gluing and screwing them together, I had the needed base which made it possible to place the printer on top of a small filing cabinet with a rather uneven top. Then I resumed the project and printed a modified top plate with corrections in the dimensions and the radius of the corners.

Since this was just to verify the size, a very thin half millimeter plate was printed as shown above. Satisfied with the result, I came up with a full 3D model adding a bottom plate with the same outside dimensions as the top plate but with different cutouts designed to hold a D1 mini that will control the display.

Unfortunately it was not possible to insert the two part 3D print into the tin. The measurements based on the second very thin prototype easily bent to insert into the tin were just too tight. A new bottom plate with limited contact with the walls of the tin was designed and printed. With a bit of sanding of the top plate, the "sandwich"

could now be inserted in the case as can be seen below.

The project is not finished: tests have to be performed to determine which type of switch would be best to wake the display after it has been turned off because of inactivity. However, I deem the 3D part of the project finished and a success.

My second project turned into something useful which is used every day. It is a simple stand for a tablet which allows me to read the electronic edition of my morning newspaper on a tablet while eating breakfast.

I will not talk more about this as I am planning on using it as a basis for a discussion about OpenSCAD. Notice that there was a problem with adhesion which fortunately does not diminish the usefulness of the stand.

Next came with a case for a Domoticz controller of my own devising. I am quite proud of that microcontroller project even if it has garnered no response. "Can't win them all" but that's OK. The rectangular cutout is for a small OLED SDD1306 display and the round hole is for a rotary encoder.

I should have waited before printing that case because I have since decided to add a buzzer, a switch and a relay. The latter has yet to be finalized. Nevertheless, I did learn something because one side is not perpendicular.

I was worried about that 9° overhang of the top edge. The case was printed upside down with the top placed on the build plate. Even if supports were not added, the top edge was well printed. There was an adhesion problem again as can be seen on the photograph.

Time has been a important constraint lately because I purchased two refurbished computers (something new for me) one of which has become a small DIY NAS. The CD-ROM reader in one of them was gutted and its shell was used as a holder for a 3.5" hard drive. There was a need for two shims between the top and bottom half of the CD-ROM reader shell and four spacers to raise the 3.5" drive about the lip at the bottom of the shell. All six small pieces were printed at once and fulfilled their function.

There was no problem with adhesion with these small pieces. This was a easy project, much simpler than hunting for a combination of washers of the right thickness and having to file them along an edge in order to fit them in the constricted space. While I had not anticipated this particular use, I think it represents just how 3D printing can be very useful.

The SSD was not well secured. A badly deformed plastic adapter was attached with only two specialized screws that fit in a slot. I replaced the plastic adapter with a metal one that I had on hand and it took about 10 minutes to make an OpenSCAD model of spacers that would fit in the slots and then only 11 minutes to print two of them with the Mega Zero. The photograph shows how the spacer, pushed down into the vertical slot and then back towards the power supply, is an adequate repair. It is attached with a standard 6/32" screw to the black metal adapter.

This time I printed the pieces with a brim and there was no adhesion problem. Even more than the previous project, this repair shows how a 3D priter can be an effective tool. It would have been possible to make a similar piece out of wood or metal with a lathe, but I don't have such a tool which is much more expensive. Nor do I have the space for a lathe. Perhaps I could have cobbled something similar with a combination of different size washers, but again I don't have any on hand and a trip to hardware stores to find something would have taken longer. Clearly, I am building my case for justifying the purchase of a 3D printer. Perhaps I am biased but it seems quite valid.

I replaced a faulty 3.5" spinning hard drive with an SSD on a computer that I gave away because there's a new rule in the house: if I bring in more computers, I must remove at least the same number of old computers. Because there was no more adapter on hand, I designed one. However it would take about 4 hours to print and I was in a hurry. So I removed all of the mechanical parts of the faulty 3.5" hard drive and used the aluminum base as a holder. I could then just use it with the bottom plate of my original design, which required only about 70 minutes to print, as an adapter to hold the SSD on the 3.5" base.

The resulting 3D print was a perfectly flat piece of plastic without any warping. This surprised me as I had forgotten to add a brim to avoid adhesion problems. Perhaps I am getting better at levelling the printer bed and at setting the initial gap between the print head and the bed. Again, this was a quick and easy solution which meant that I did not have to wait for weeks if not months for a part purchased over the web.

Given these examples and the many electronic projects presently on breadboards that would benefit from some sort of permanent case, I have concluded that purchasing a 3D printer was a very good idea. It has already proven its use and it will become one of my most used tools in the future.

Now what about the ANYCUBIC Mega Zero itself? I can report that assembly was simple. The more complicated base and print bed are pre-assembled as is the hot end and Y-axis gantry. Basically, assembly amounts to tightening a few nuts as the vertical frame is attached to the base. Again, look at Ben Heck's video for details. As for calibrating the printer, all I can say is that I have yet to do that. I just build the projects as described above. That is not to say that the prints are dimensionally perfect, but the Z-axis is almost there. Along the X and Y-axis, the prints are only very slightly bigger than expected (say 0.2 mm over a 50 mm distance!) The probable explanation is that the printer is mostly pre-assembled at the factory. It does look like holes tend to be smaller than specified, but that is not really a problem as they can be drilled out to the wanted diameter. The printer is noisy, but that appears to be a common problem for low-end machines. Beside there is a solution that I have already started to implement: OctoPrint on a Raspberry Pi 3 - the Hard Way.

A word about support from ANYCUBIC. I made a mistake trying to remove the filament which got stuck in the extruder. The technical and after-sale staff responded to my queries very quickly, and helped solve my problem in a refreshingly friendly fashion. They are obviously used to dealing with bumbling new users. To be honest, I was amazed with the help I got especially in light of the price. When asked by the to rate the Mega Zero, I agreed. I wrote a short review with some of the elements found in this post but Amazon rejected it. It turns out that I should not have included the URL to the Ben Heck video. Since Amazon will not let me resubmit my review, I decided to write this post in an attempt to be true to my word. This is when I saw the price drop for the Mega Zero, at least for American customers, which only encouraged me to go ahead as quickly as possible.

In conclusion, I am very happy with my choice and do not hesitate to recommend this printer for any other beginner that, like me, just wants to try 3D printing before committing to a large expense. I can only image version 2.0 of the Mega Zero is an improvement. Perhaps it will be my next choice when September rolls around and my self-imposed moratorium on purchasing another printer comes to an end.