RoadTest: CEL Robox 3D Printer
Evaluation Type: Independent Products
Did you receive all parts the manufacturer stated would be included in the package?: True
What other parts do you consider comparable to this product?: At Leeds Hackspace we have a comparable 3d printer that is self-built according to the MendelMax design.
What were the biggest problems encountered?: The initial unit’s head jammed completely when attempting to print with a standard nylon filament, the parts variously do not stick to the bed and the print quality is variant even when printing the same models.
Headline of review
A respectable 3d printer but not one that “breaks the mould” as I was hoping.
The Robox is certainly a nice-looking printer that wouldn’t look out of place in a lot of SO/HO studios, and it has some very nice advancements over your average RepRap printer, so I’ll take a look at some of these first:
So, that’s the main features that are unusual for a 3d printer to have, onto print quality:
The quality of prints from the Robox can be outstanding, the “fine” setting is really impressive, a lot due to the very fine lead screw that the printer uses to get very small layer heights. Unfortunately the repeatability if fairly low, and delamination occurs even with the provided filaments.
(Delamination on dalek and failed layers on the cylon raider)
The overhang quality is relatively weak also and leads to sagging. When printing technical parts like SD card slots that’s a really annoying thing to have to work around.
(Poor overhang on the dalek lights on PLA and even on the rings on ABS)
If the print doesn’t stick, it can lead to warping of the base, which I have experienced even with PLA. I know some neat tricks to get things to stick (dilute PVA glue for PLA and ABS dissolved in acetone for ABS) but then the prints stick too well and are more likely to break when removing them.
(warped base on PLA)
The printer’s Bowden-fed system also rules out some of the more interesting flexible filaments as they really don’t handle Bowden-feeding. This is the case with a lot of smaller printers, reprap and commercial alike, as having a direct-drive system causes other issues that this printer avoids.
It was my intention to attempt printing with multiple materials on this printer, as I do with all my reprap experiments. Unfortunately given the no serviceable parts nature of this printer, I have had to stick entirely to ABS and PLA. My initial attempt to print with nylon caused the head to jam and the printer had to be returned.
Initially the bundled automaker software (which I had to redownload in full off the internet because it was “out of date”) used the Slic3r software which using it’s default settings wasn’t great, however in later updates, the software has switched to the Cura engine which is much nicer or at least is much nicer with the settings that come with it.
Talking of software… ugh. Closed-source software that uses 3d libraries in java that only work on Windows or Linux machines with nvidia cards? During my experiments, it appears it is just about possible to use something like pronterface directly but only a minimal set of g-code was accepted. I run multiple printers from one machine and whilst tinkering on one of my others when the robox was printing from memory, I selected the wrong serial port. When I sent a standard g-code to the robox by mistake, it stopped and wouldn’t talk to anything until I rebooted it.
Would I recommend a Robox to friends?
I’m not sure I would, no. CEL have made a valiant effort to make a “works out of the box” 3d printer, and I applaud them for their efforts, I really do, but FDM 3d printing is not in that zone yet. If it were repeatable quality at its best settings, had better overhang performance (without support, that’s almost never the right solution), and didn’t delaminate, then maybe yeah as a “set it and forget it” printer it would be brilliant. Until that kind of printer comes along, I’d stick with my firm belief that if you want a 3d printer, build it yourself because if you do, you know how it fits together, and when – not if, but when – it breaks, you have a much better chance of fixing it.
To end the review on an upbeat note, it did print the octopus in very nice detail in abs, which by coating it with graphite powder suspended in acetone to make the surface conductive, I was able to electroplate with copper :
(Copper-plated ABS Octopus)
It's worth noting that since this review, the printer has started skipping and jamming more. I have the option of sending it back for repair (not certain if the warranty for a free printer would be honoured) or attempting maintenance that would definitely void the warranty. I have also had others say they had the same problem and sent back the unit for a refund as they could not justify sending it back every time it starts skipping or jamming. It's a real shame as when it works it's a lovely printer, but when it stops working you are completely without recourse except shipping back to the manufacturer for repair or refund.