Everything that’s wrong with Creality 3DPRINTMILL (CR-30) – the 3D printer with “infinite” build area

At the end of August this year Creality – one of the most popular Chinese manufacturers of amateur 3D printers, presented the design of a device equipped with a conveyor belt instead of a printbed, which allows 3D printing of theoretically infinitely long parts. The 3D printer called 3DPRINTMILL (CR-30) was created in cooperation with the controversial YouTuber – Naomi Wu, who has been expressively promoting it on her social channels for several months. In mid-November this year Creality has launched a campaign on Kickstarter, where it offers the new 3D printer for about $ 700 depending on purchase option. It’s target price will be $ 999. The shipment of the first devices are to start in May 2021.

Although the idea behind a 3D printer equipped with a conveyor belt is nothing new, until now, devices of this type have not enjoyed much popularity. One of the first proponents of this solution was the Dutch Blackbelt, presented in May 2017, and Brook Drumm also tried to create his version from the now defunct Printrbot. Thanks to its market position (and the media support of YouTube celebrities), Creality has a chance to change that. The only question is is this a change that anyone should wait for…?

Creality 3DPRINTMILL (CR-30)

Let’s start with the technical specifications. In terms of design and components used, the 3D printer does not differ from other flagship Creality products, with Ender at the forefront. It is made of the same profiles, has an identical Bowden type extruder and the same printhead. We buy it in the form of a kit for quick and easy self-assembly (the individual parts are already assembled). For this you use ordinary hex wrenches attached to the 3D printer – similarly to the Creality CR10 series, putting the device together should take no more than half an hour.

The most important differences from other FDM / FFF 3D printers are the printhead mounted at an angle of 45° in relation to the table and the printbed in the form of a transmission belt. The belt is made of nylon and, according to the manufacturer, it is designed to last for several years. This solution completely changes the way details are created in this technology, but I write more about it below. A specially modified CURA is used to handle and prepare 3D models for printing.

Detailed technical specification:

• build area: 200 x 170 x “infinitive” mm
• 3D printer dimensions: 535 x 656 x 410 mm
• max. printhead temperature: 240°C
• max. bed temperature: 100°C
• weight: 16.5 kg
• printhead diameter: 0.4 mm
• filament diameter: 1.75 mm
• printed layer height: 0.1 – 0.4 mm
• communication: USB / SD card.

What’s wrong with this 3D printer?

A few weeks have passed since the premiere of Creality 3DPRINTMILL (CR-30) on Kickstarter and on YouTube we will find a lot of videos presenting how the work with this 3D printer looks like? Although the YouTubers try to be reserved in their judgments, they all point to the same problems that indirectly question the sense of the existence of such machines…?

1. Eight bed calibration points

Every user of FDM / FFF 3D printers knows that the key to success is always a well-calibrated printhead in relation to the heatbed. If the first layers of a print adhere well to the surface of the bed, most of the potential problems with 3D printing are already resolved. Depending on the type of 3D printer, the bed are calibrated using 2-4 knobs (I omit systems equipped with auto-calibration or auto-compensation systems). The ability to calibrate is the first basic skill that every user of an amateur or desktop 3D printer should acquire.

In the case of Creality 3DPRINTMILL (CR-30), the table is calibrated in four places – the same as in the case of other 3D printers of the manufacturer, with the difference that the knobs are on the top of the housing, not underneath. However, this is not enough… To fully level the printhead against the bed surface, you also need to adjust the two endstops on which the arm with the nozzle move. You also need to stretch the conveyor belt properly (the tensions on the left and right sides are used for this) – if it is too loose, the prints will not stick to it well, if too tight… the stepper motors will overheat.

While after some time mastering the above-mentioned calibration should not be a problem, having a lot of experience in working with the Creality CR10-S, I know how annoying it can be. Here, the manufacturer multiplied this activity. For novice users for whom this would be their first contact with a 3D printer, this can be a real torment…

2. Surface quality of the first layer

The conveyor belt has a characteristic texture that strengthens the adhesion of the 3D print to its surface. Unfortunately, this pattern imprints on the first layer of the printed part, which will be disqualifying for some applications.

It may turn out that, as in the case of Zortrax 3D printers, it will be necessary to print parts on the raft by default. Which might not be a bad thing, if not for the fact that working with raft generated by CURA software is far from perfect…

3. 3D printing always at an angle of 45°

We come to the biggest problem related to working with Creality 3DPRINTMILL (CR-30). The printhead is installed at an angle of 45° to the surface of the printbed and thus applies successive layers of material. As a result, the layers are arranged completely different than on traditional FDM/FFF 3D printers. In the case of some models it facilitates their creation (see printscreen below), in others it practically prevents the correct production of the part.

This can even be seen in the official video promoting the 3D printer by Naomi Wu, where the CR-30 prints a whole series of 3DBenchy boats, having the same disastrous tailboard quality.

This change in the position of the head makes it necessary to approach the issue of placing 3D models on the workbench completely differently (so we forget about everything we have learned so far in working with classic 3D printers), as well as designing details themselves.

As an interesting fact, the traditional understanding of the 3D printer axis has been completely disrupted on the new Creality. In “endless” 3D printing, the X axis is suspended in the air at an angle of 45°, the Y axis moves the head up / down, and the Z axis is the conveyor belt. That is, the “infinite length” of a part corresponds to its height in the traditional understanding of FDM / FFF 3D printing.

4. And those things that can be 3D printed endlessly are…?

Adapting the project and its optimization in relation to a specific device is not a bad thing, but the question that should be asked is – for what? What is so special about 3D printing on Creality 3DPRINTMILL (CR-30) that could justify a new, special approach to design?

Let’s go back to the technical specification for a moment: the working area we have is 200 x 170 x + ∞ mm. While the last dimension looks impressive, the first two are not that much. It turns out that with the CR-30 we can manufacture long, but at the same time thin and short details. YouTubeers 3D prints for example some swords:

Or very long profiles:

Or a dinosaur:

After all, so far no one has presented an application that would be valuable enough to be worth considering this particular technology? But it’s also fair to emphasize that it is worth giving users some time – the 3D printer will not physically hit the market until next year. Is it possible that in a while there will be someone who will use Creality 3DPRINTMILL (CR-30) in a truly unique way?

Of course, with the CR-30 you do not need to 3D print one long detail – you can also produce many small details in series. Unfortunately, here comes another problem that makes this idea bad…

5. An infinitely long 3D print takes an infinite amount of time

Creality’s innovation is selective. While the use of a conveyor belt to enable the production of infinitely long elements is innovative (omitting the fact that the original concept was invented by someone else and copied in several different ways by others), the rest of them remained exactly in the same place. I mean the quality and functionality of the components used. The speed of 3D printing has remained the same as in the case of Ender or CR-10, thus the “infinitely long 3D print” will print “infinitely long”.

For example, on the promotional video of Naomi Wu, 3D printing of a long profile takes about 1.5 days (we can calculate it based on the view from outside the window), which with relatively simple and small geometry of the detail (in the XY axes) makes the whole project unprofitable . In fact, Creality could create a classic 3D printer with a Z axis extended to several meters – the performance effect would be identical. For this type of solution to be really functional, the fast filament extruding system should follow, allowing really fast work and quick production times.

Thus, low-volume production also loses some sense – it is no different from 3D printing details on an ordinary Creality. Maybe apart from the fact that on the CR-30 we 3D print one detail at a time, while on a classic, “closed” table, they are all produced simultaneously. I don’t think this type of change could be seen as groundbreaking? At the end of the day, it will turn out that when we take into account the time factor, producing several dozen / several hundred pieces of details on the CR-30 will be as expensive as the corresponding production on SLS or MJF industrial machines. Except that the final quality will be incomparably worse to EOS or HP systems.

Summary

The Creality 3DPRINTMILL (CR-30) is so far nothing more than a curiosity – a kind of supplement to the existing manufacturer’s offer with an unusual design that no one else in direct competition has. Certainly there is no question of a revolution or game-changer. The price of a 3D printer is so small that it is quite likely that next year we will become owners of the CR-30 ourselves, which we will just play around for some time. Who knows, maybe we can even fulfill one or two unusual (and cheap…) orders with it?

The 3D printer is definitely not intended for novice users, because the scale of differences and technological imperfections resulting from the specificity of the production process itself may make them discourage from 3D printing in general.

You can discuss Creality 3DPRINTMILL (CR-30) on our LinkedIn group: AM Industry Survival Guide.

Source photos:

• Cover photo – Kickstarter
• Naomi Wu
• Maker’s Muse
• 3D Printing Nerd
• NAK 3D Designs

Photos used only as a right to quote in accordance with Art. 29. Right to quote Copyright and Related Rights Act.