Saturday, 9 January 2016

2016 Projects ...

Is this the last RepRapPro Mendel?
Preceded not so long ago by Nophead, RepRapPro are closing. Leaving those who purchased a RepRapPro printer with slightly less support or warranty than might have been assumed.

For Christmas, my wife insisted I have a new 3D printer. She said you can have any printer you want, honest! For me at least there could be no better device than a RepRapPro Mendel. So, I have in my hands what is likely to be the very last original RepRapPro Mendel ever built! Though like RepRapPro hope, probably not the last ever built.

In the best traditions of RepRap, perhaps Adrian would be pleased to know. I am busy printing the parts for my Mendel on Huxley #710 in a RepRapPro green. Printers printing printers, absurd!

Anticipating many excellent years service and trouble free operation to come. Using the detailed design files and instructions (~ 2 Gb in total). Probably never needed, to maintain the ultra reliable extruder head(s). Unlike a certain also well known 3D printer that was under consideration by my wife.

When it's finished, it should look something like this:

A RepRapPro Mendel 3 - December 2015

Later Edit:
Reprapcentral ( went mid late 2015, I couldn't find out what happened to them.


  1. Thank you for the picture I assumed that was how the extruder was attached to the Mendel. I to received my Mendel just before Christmas and have been busily building, I just wish the online instructions included this build. Where did you ever find that picture?

    1. I have to honest here, I pulled all the details off the website I thought I might need.
      Hi Kevin, if you have read my blog, you will see I have a few years experience with Huxley #710
      If you need to and can't get some answers, drop me a line, I will do what I can.
      Also check out the IRC channel RepRapPro.
      If Huxley #710 is anything to go by, you have a superb machine.
      Keep in mind it's open source so there are other sources and plenty of data about.

    2. P.S. one wrinkle I found. On my fan harness, the molex connector for the pcb of the fan cable blue and green connections were the wrong way round. I understand the fan only runs if the connections are the correct way round. This is very important as the fan MUST run to keep the heat sink cool. If this fan does not run, heat from the hot end warps the X axis hot end mount. Strongly suggest testing heating for a very short time, and check the fan runs. On my machine, I had the fan facing away from me! At least I knew to check it was running.

    3. This is good thing, now that I'm past that stumbling point I'll start on the electronics tomorrow. Thank you for the tip I'll keep my eye out for that problem.

    4. Possible further wrinkle. I found the extruder motor direction reversed. I think I carefully checked connector wire colour order etc. It's very easily changed by modifying the file in the SYS directory of the SD card. Just place a semicolon in front of the line(s) for the extruder. Would love to hear if you had the same experience.

  2. Up and running. It was an uncomfortable experience watching the head home in on the glass, it is close!

    Yep, extruder motor is in reverse! I haven't found any other problem with the build up to this point.

    I have another board in the box that I haven't the foggiest what it belongs too. It says Duet Shield on the face of it. It would be awesome if it ran another head and extruder; a fourth colour, would be a bonus.

    1. If it says Duet Shield, has tons of white Molex connectors and two big TAB connectors then its a multi head shield. Rare beasts indeed. Here's a link to what I think you are describing.
      ~85 USD present - NICE!

    2. Hint on the hope script for the Z axis, take out the last command that sends it to Z0 position.

      I can't see the need for this at the moment.
      Also watch out for the X30 position commands in some of the script files.

      Below is my homez.g file as of today, note the two changes X40 and the semi-colon

      G91 ; set movement to relative mode
      G1 Z5 F200 ; move Z up 5mm
      G90 ; set movement to absolute mode
      G1 X40 Y0 F2000 ; move X and Y to probe point. ADJUST X and Y values to get Z probe over target.
      G30 ; home Z, using values from G31 in config.g
      ;G1 Z0 F200 ; move Z to Z=0

    3. Very nice you are up and running! I'm way behind you; this is my first printer and I'm on a pretty steep learning curve. The closing of Reprappro is a serious loss for me.

      The duet shield is as you've described. Now that I've read up on it, I understand more of it functionality. I'm beginning to have a great respect for the genius of Adrian Bowyer.

      Please continue to post your findings and progress; I'll patiently wait to hear!

  3. Printed the calibration 200x200 test piece; it could have gone better. To correct the extruder direction I pulled two pins and reversed them on the molex connection. Instead of ABCD I have BACD and now it extrudes correctly. I also placed a white sticky tab on the X home tab for the optical IR sensor. For some reason pronterface is sending 210mm of material for the 100mm command. That's easily fixed but I need to figure out why it came that way.

  4. OK, now that I have spent some time reading code and have a decent editor I see flipping wires is necessary. Back in the Unix/Fortran days I used gedit but now with Windows I've found notepad to be useless. I installed a programming editor and the code looks much better!

    1. Hi, you can use Wordpad in Windows. I haven't tried to change the format to a simpler text file yet. However suspect it might work.

      To reverse axis without resorting to changing the wiring. You will probably find in the config.g file lines
      M569 P3 S0 ; Reverse the extruder motor (T0)
      M569 P4 S0 ; Reverse the extruder motor (T1)
      M569 P5 S0 ; Reverse the extruder motor (T2)

      Put semi colons in front of them:
      ;M569 P3 S0 ; Reverse the extruder motor (T0)
      ;M569 P4 S0 ; Reverse the extruder motor (T1)
      ;M569 P5 S0 ; Reverse the extruder motor (T2)

      This will allow the motor direction to work as needed.

      You might also like to set a more appropriate extruder scaling.
      This is where I am at the moment, setting all steps per axis on one line:
      M92 X87.489 Y87.489 Z4000 E250

  5. Very good, thank you. I had a loose stepper motor keeper on the y-axis that made for some pretty interesting orthoganal z layers. After that discovery I went back through and measured everything to get it as square as possible.

    I commented out the extruders as you outlined above and switched the wires back.

    I intend to go to the hardware store tomorrow and make an adjustable stem for the plate. I have about a 2mm difference between the y-axis that I'd like to reduce to 0.5mm.

    What 3D software do you use? My son uses TinkerCAD in school.

    1. Hi, I use two packages. Freecad and a very old package, Pro-Desktop. It was used heavily in schools, though is now deprecated. I must be one of the few left using it as I 'adjusted the free version'. I had far to much invested in part libraries to dump it when they 'pulled it'. Pro-Desktop was replaced by (in my view inferior) software called Creo. Solidworks is widely regarded though somewhat expensive to say the least. Quite a few people use TinkerCAD, though I rejected it due to its rather painful birth (

      Which ever CAD package you choose, you will need a copy of Netfabb (it has a free restricted version) to 'fix' STL files.

      Check out this chart
      Love to hear what you decide to use.

  6. That was a fun read! My son has been using TinkerCAD and since it is free we'll be using it for our 4-H group. We presented the Mendel last night to everyone's amazement. Since he is a student it appears we can get Solidworks for $150. I'm not convinced he needs it yet but it give the lad a head start on things.

    Now onto installing the other two extruders....without direction and support. There's a fair amount of information on Reprap and I hope it's covered.

  7. I've searched the reprappro, github, and reprap website for directions for the tricolour portion of the Mendel. I can't seem to find the photo you have posted at the top of this blog and wonder if being in the US is the problem with access to your local content there. (Perhaps I'm seeing a mirror server?).

    Could you share with me how you acquired the photo at the top?

    1. I am sure it's not geo location restricted.

      Ping me a personal message through Thingiverse with your e-mail or some other way. I couldn't find your e-mail address from the post. I will forward what I have, as It won't go in these comments.

    2. Took me a while to find a link.
      Follow the links on the right!

      Drive mounting is a "Picture to come"