In the market for a truly hardcore 3D printer? Then you should consider the Makertoolworks MendelMax 3. Thomas Sanladerer gives us the low-down. For more details, read this Mendelmax 3 review.
Note: This review originally appeared on Thomas Sanladerer’s YouTube Channel and is subject to copyright. Text and images have been reproduced with the author’s permission.
The MendelMax 3 is not your typical 3D printer kit in a lot of ways. While the earlier MendelMax 1, 1.5 and — to a certain extent — the MendelMax 2 were still RepRap-style printers with lots of printed parts and off-the-shelf fasteners and rails, the MendelMax 3 heavily builds on custom sheet metal parts.
They’re all nicely powder-coated black and, along with large amount of OpenBuilds V-slot profiles, give the printer quite a bit of heft. And seriously, this is very much a beast of a printer.
The one I got here is the all-out dual extruder version, featuring two E3D v6 hotends, a pretty massive 250 by 315 by almost 200 millimeters build space, a heated bed running off of the 24V supply, Openbuilds Xtreme Solid wheels and matching rails on all axes, a genuine Ultimachine RAMBo to control it all, as well as some LED lighting that serves as a smart status indicator.
But let’s start chronologically. The MendelMax 3 is a printer kit, so the entire building and calibrating process is something you get to do yourself.
And you better enjoy assembling these kind of things. Just the build itself took me thirteen and a half hours, which I split up into a few evenings and weekend build sessions.
The parts of the kit were all very, very nicely machined, and during assembly fit together pretty much perfectly… Except for the few printed parts that needed some of their holes reamed. But all the sheet metal parts have spot-on tolerances and no sharp edges, the openbuilds v-slot profiles are very nicely anodized, very straight and cut the the exact right lengths, and even the included hex wrenches are top quality stuff.
But I guess the wrenches had to be of decent quality, because you will be using them a lot. If you look at the included number of fasteners, be it screws, washers, t-nuts or regular nuts, it’s pretty apparent that this is not going to be a simple build.
The fact that the instructions were not always all that clear didn’t help, either, I found myself redoing quite a few steps because I ended up assembling stuff mirrored or in the wrong sequence. Some of the instructions mention using one, two, or no washers for specific sections, only to later on leave you confused with seemingly contradicting information. Or no information at all: in the later stages of the build guide it just says “assemble this part” in a few sections.
That being said, the way things fit together did make sense in the end, and even without clear instructions or good images of some the sub-assemblies, the printer turned out alright.
And I know the folks at Makertoolworks are already working on improving this guide, but also (and I actually tried this out anonymously) they have a superb web support platform, basically an IRC channel, where there seems to always be someone from Makertoolworks available to help you out. It might take a few minutes until you get an answer there, but it surely is faster than logging your question into some anonymous support ticket system that will only connect you with a customer support agent in India. We’ve all been there.
By the way, Makertoolworks is based in Oklahoma.
The other thing that delayed my assembly by a fair amount was the fact that the kit had quite a few parts missing. Some of them, like metric screws and washers I had at hand — the MendelMax uses 100% metric parts — but others, like a few parts from the second extruder kit, a corner bracket or some sheet metal parts, were not so easy to replace.
Thankfully, with this being a review unit, I got spares shipped incredibly quickly. But then again, stuff like this shouldn’t be an issue, especially not with a review unit, but I guess if you’ve got so many fasteners in a kit, it’s quite easy to miss a few.
Now, after the assembly, there’s one more tricky bit, and that is adjusting the bed. The bed consists of a Kapton heater stuck to an aluminum heat spreader, on top of which there’s a glass sheet.
Then this entire assembly sandwich is clamped onto the bed platform with three brackets; in two of these, there’s a screw below them that lets you adjust the height, the third one is fixed. The problem here is that not only do you awkwardly have to work on adjusting these from below the printer, but you can also only adjust them if the nozzle is at the opposite side of the spot you’re trying to get to the right height.
So that’s kind of a bad design, and it takes way longer to tram the bed than it should. Mine still isn’t perfectly adjusted, and I really have to wonder why this printer does not have an inductive sensor doing all that tramming jazz for you. And that would have made that entire assembly a fair bit simpler, too.
But the bed is almost the only spot where I can really complain about the final, assembled MendelMax 3, because the entire design seems to have a different philosophy than a lot of the other “full size” printer kits out there today.
It’s a bare bones machine. It gives you all the essential components that you need to get printing, makes those really high quality, and leaves out everything else that you don’t strictly need.
That includes things like drag chains, which are pictured in the official shop images but aren’t actually included with the kit, fan mounts and air guides for the part cooling fans, filament guides from the spool mounts to the printhead, and any sort of cover for the mains wiring inside the printer.
Yes, you heard that right, there is exposed mains wiring inside the MendelMax and it’s shockingly easy to get your fingers in there when reaching below the frame. I already ended up soldering the connectors onto the switch and plug since they were the wrong size for the tabs, but at no point do the instructions mention anything like at least adding some electrical tape over them.
So this is definitely one of the upgrades that I’ll be doing shortly, the other ones, like those drag chains, can be printed piece by piece as you customize the printer to truly make it your own.
Software-wise, the MendelMax 3 runs a customized version of Marlin to support those LED strips, which have their own back power supply and Arduino to control them.
On the printer host side of things, Makertoolworks provides a licensed and branded version of Repetier Host. Which is constantly trying to make you buy its Android or iOS app. Really?
Repetier Host isn’t my favorite host software and can be somewhat confusing to get into, but it does the job and the installer even provides you with a Slic3r profile for the MendelMax 3 that you can use independently of the Repetier host software.
And while the default profiles don’t include anything fancy like custom start gcode or optimized extrusion widths for the first layer, they do work surprisingly well to get you started. Sure, the retract settings and minimum layer times could use a bit of tuning, but again — bare bones.
These are not inherent flaws of the machine, but tweakable and customizable settings that you can mess with as much as you want.
The print results again showed that the core mechanics of the MendelMax 3 have very little left to be desired.
The OpenBuilds wheels and rails provide an extremely rigid framework and the high-quality motors, pulleys and belts do the rest. For the Z-axis, the ends of the spindles are even properly machined to fit the couplers, so Z-wobble is an absolute non-issue.
As expected, the extruder-hotend combo also had no issues with printing ABS, PLA or Nylon. Maybe a stainless steel filament drive gear would have been nice instead of the brass one for longevity, but really, that’s complaining on a very high level.
The extruder overall is also massively built. Maybe even a bit too complex, but you know, better safe than sorry. The tension of this guy is adjustable, but you should rarely need to fiddle with that once you’ve found a setting that works for you.
Now, what I’ve been ignoring so far is that I’ve got the dual-extruder version. The two V6 mount into an aluminum holder that lets you clamp each hotend individually with a pair of grub screws to get them to the same height. While that works well enough, I don’t see why they didn’t simply go with an E3D Chimera instead, which would have made that entire offset fine-tuning easier when the two hotends don’t perfectly match up — and they won’t — but, again, would have also made the assembly smaller. And simpler. And cheaper.
I gave dual-extrusion a try and, yeah, I managed to print a dual-extruded part, again, with the stock settings. It doesn’t look too nice, but honestly, I’m not too interested in printing two-color items anyways.
What I think dual extrusion is going to be the most useful for, at least for the things I typically print, is for printing water-soluble support material, which should solve a lot of problems instead of creating new ones.
So to sum up the MendelMax 3 experience, this is not a plug-and-play printer. Not by a far stretch, and you will end up frustrated and disappointed if that’s what you are expecting.
What you are getting here is a platform — yes, it does already print very decently once you managed to assemble the thing, but then there’s still so much room for improvement. Or even total conversion: I’ve looked into mounting a Dremel-style rotary tool to a few of my printers before, but the MendelMax 3 is the first one that seems beefy enough to handle such a tool.
Now, would I recommend the MendelMax 3? Yes, absolutely, but definitely not as a beginner’s printer.
If you want an upgrade from something like a Velleman kit or an older Printrbot and are looking for the next big thing, then by all means, this is a great option for you. While the MendelMax 3 is neither a real self-replicating RepRap nor currently an Open Source design, it still firmly occupies the territory that the high-end RepRaps used to hold.
And for a sticker price of $1495 for the single-extruder version, or $1645 for the dual-extruder one seen here, it’s decent value, too. Sure, the design could be manufactured cheaper in a lot of ways. But compared to what the alternatives are in this segment, well, there aren’t really any alternatives if this kind of printer is exactly what you want.