Review: MendelMax 3
Printer showed up without critical parts so I had to wait another week for parts to arrive. The assembly guide is online only and is mediocre. I often found myself putting something together then having taking if off and putting it on correctly the second time. They forgot to mention certain parts like the bltouch connector holder. Most of the parts are labeled or obvious but many you have to compare against assembly instructions to figure it out. The printer is not designed for easy assembly. You will have to the frame together and continue working around tightening, loosening, adjusting until you get it square. I also had a lot of issues aligning the lead screws so that I had to remove the x gantry and run the lead screw nuts up and down while adjusting. The instructions had fan mounts for a different fan type so I had to go to the discord to get the proper ones that weren’t exactly right, had to stack 2 for clearance to carriage. The wiring is laid out with 2 pictures of a good looking layout and no detailed instructions. A 3D PDF model is available but not really useful as small parts are missing and it’s hard to manage all the assemblies so you can see what you want. There is support through Discord that typically has 1 or 2 of the main guys that can be very helpful and they are available a lot.
They suggest MatterControl for host/slicing. MatterControl has unfixed bugs on Linux that made it unusable for me. I’ve been using PrintRun for host software and Slic3r PE for slicing which have been working fine.
Design is simplistic and leaves options open for upgrading over time. The frame is rock solid. Control is through a RAMBO 1.3 board with configured Marlin 1.1 supplied. Motors are sized properly to move the heavy axes. The details is where everything goes downhill. The x idler mount is poorly designed and has come loose several times leading to failed prints and failed homing that nearly took out the bed. Bed mounting is not solid, making it an absolute chore to get it level and keep it level. The bltouch mount is not solid as assembled according to the instructions so it will be wildly inconsistent until you properly secure it. The extruder is simple, stiff and is designed to allow a second extruder to fit on the x carriage. The extruder is a liability because the drive gear is off by about 2.5mm from hole in the heatsink meaning the filament is forced sideways into heatsink leading to feed issues from the awkward angle and filament bending. The hotend is a e3d V6 and works great. The printer came with 2 40mm axial fans for print fans which are the absolute wrong choice. The printer needs directed cooling by the nozzle to print properly. The confusing part is that they used to provide blower fans and .stls for fan shrouds that worked fine and are what I ended up using.
I had tons of printing problems. The core issue is that they supplied axial fans and no base profile. The axial fans would not provide enough cooling or would cause thermal shutdowns by overpowering the bed or hotend heaters. I ended up having to buy blower fans from them and print fan shrouds from stls they provided. You’re supposed to print the fan mounts by somehow macgyvering the fans onto the axis using zipties so you can print the cable chain and fan mounts. The lack of wiring instructions lead to wires coming loose during printing causing further printer shutdowns.
Once everything is properly setup, you can get some really nice prints. The extrusion is very consistent and motion is rock solid.
Printer has a lot good components and upgradability, but the missteps on the small things make this more of a project than a printer.