Mendelmax 2.0 / 3D Printers in general- A review, and some thoughts.

Well, with a few successful prints under my belt, I think its time to write a few of my thoughts down.  These printers are incredible machines.  It is something else to draw something up in Sketchup, click a few buttons, jiggle a few switches, and then sit back and wait for an actual thingamajig to come off the printer.  My wife thinks its pretty funny, but me and the boys will sit and watch it print- back and forth, back and forth, for hours on end.  My students have been totally enthralled with it- anytime it's running they want to stand around and gawk at it.  Maybe they just want to avoid working on their assignments?  Nah...

Previous to this expereince, I had ZERO time playing with 3D printers.  I did get an Associates degree in Manufacturing Engineering like 10 years ago, which had a fair bit of CNC experience, and that helped a bit.  There is litterally thousands upon thousands of pages of information out there on the internet, and many different resources for setting up your own printer. 

What does all this mean?  Well, I don't know how qualified I am to review the Mendelmax 2.0, but here's my take on it.  Given my background I would consider myself as one with great skills when it comes to the mechanical end of things, but only mediocre when it comes to the electronics / software end of things.  I will admit- this was a HARD project for me.  It took a lot of time and I had to do a lot of research and trial and error to get prints.  I do feel though that as this specific printer moves from the beta testing process into a more refined package for resale, many of my headaches will have been eliminated.  Many of the issues I have had have already been adressed, and as more people build and use this printer the support group and information will expand exponentialy. 

As for print quality.  Again, I don't have much to compare it to, so here's my take.  From what I have seen, the quality coming off of my printer is excellent.  There are hundreds of varialbes that affect the quality- type of plastic, size of nozzle, extruder, heated bed, design of parts, and on and on.  In addition to the physical factors, it does take some practice and some skill to get the printer aligned and calibrated each time, and to know how to design prints to be successfull.  It's all part of the huge learning curve.  Again, thankfully, there is a lot of info and a lot of people out there willing to help you become successfull.

I full intend to use the heck out of this machine in the classes I teach.  I don't see any reason why it isn't up to the task of running just about continuosly day in and day out in a middle school setting.  Sure, things will probably wear out or need adjusting, but it's a well built, well thought out design that can only get better- that's the beauty of REPRAP's or REPSTRAP's- everyone can littlerally print their own improvements.  Heck, I've already got an idea to adapt some ideas from a MIG welder to my extruder to make it much quicker and easier (without tools) to change plastics.

Can't wait to see where this thing takes me.  For now, we'll call the assembly and testing done.  Keep in mind I will still have to do the z-axis update when it shows up, and I still plan on doing a lot of posts here about how to set up prints, slic3r settings, different plastics, and other little tips and tricks I've picked up doing this.

SO.  Lets call it an even 18 hrs. to build, test, and get some decent prints off of this printer.

I feel now that I've done it, this could be DRASTICALLY reduced-  I think  much more reasonable estimate should be 5-10 hours for the total newby, and possibly quite a bit less for the experienced builder with all the tools and know-how from previous builds.

What would one of my posts be without a ton of pics?!

Some bling, both from Makers Tool Works and the school district...



The "finished" printer. Still need to make a spool holder for the plastic among many other things...



 Several of my trials and errors.












Kids sure love to watch it!

Mendelmax 2.0- FIRST PRINT!!!

Once you have the firmware uploaded, you should be able to manually control your printer, like this:



Then you can start playing with things.  If motors go in the opposite direction than what they are supposed to, its very easy to simply turn the connectors around.  FIRST POWER DOWN the printer, as unplugging a motor while its on can blow the stepper driver.  It's kinda fun to push buttons-  here's a screen shot of the temperature curves using Repetier:




Once you have a handle on how things work, lets try a dry run!  I set it up to think it was up high in the Z and roughly centered on the X and Y so that if it decided to move a long ways I would have enough time to stop it before it crashed.  I also left the X and Y belts loose so they would skip if it did crash...  I quickly drew up a simple shape in Sketchup and ran it through the differen programs to get it ready for the printer.




The software even draws it out for you while it goes. Dry run successful!
 

 Ready to melt some plastic!?  This is a little more tricky.  You have to get the plastic fed into the extruder- had to loosen the clamps on the side, heat the nozzle up, and push the plastic through until it started coming out the end.  Clean up the mess.  Reset the home position, and press PRINT!  It will take a few minutes for the hot end and the bed to reach operating temperature, and then the printer does its magic.

In progress.









Finished and cooling.



The real first print on the left... had the nozzle too close to the glass. Second one turned out pretty good!





Looonnng ways to go still, but at least its functional! I spent some time during this process to adjust things- it also took me a while to research and then execute setting the home position.  There was also a trial and error process involved with getting the nozzle the right height off of the glass- which would not be there if I had the endstop switches.  Again, I think this process could have been a lot faster, but that's the way the cookie crumbles.  I do plan on doing a series of posts on how to setup, calibrate, and run the machine so hopefully those in the future won't have to spend so much time researching things like this!

Time Spent on this step: 2 hrs
Total time so far: 16 hrs. 15 min.

Mendelmax 2.0 / RUMBA Board Firmware & Software

I'm going to preface this post by saying 2 things: 1.  I am NOT a programmer, and 2.  This was a royal pain in the butt for me.  On the bright side, I think I actually remembered some things from the C++ class I managed to (I think...) keep my eyes open in, and they came in handy.   I opted to use a RUMBA printer control board (no idea why... seems like someone said its the one to have?).  It is still a brand new, fairly untested control board and as such there isn't a lot of info out there on it.  It is supposed to be extremely similar to the RAMPS 1.4 board, but I wouldn't be the one to ask what the similarities / differences are.  I did have a combination of issues with the board- it would appear that either the included USB cable is bad or the USB connector on the board is wonky.  Ended up using a different USB cable and cutting the end off and attaching to the optional pins on the board.  Seems to be working fine now.  Sounds like there have been a few others with bad USB cables, not sure if anyone else has had issues with the connector though.

Alright... so here's the how to get drivers / firmware uploaded... After spending 3 frickin hours last night trying to get this to work only to discover a bad usb cable this morning. Not going to count that 3 hours in the overall time either.

First step: Download the RUMBA drivers from here: http://reprap.org/wiki/File:RRD-RUMBA_USB_DRIVER.zip

This part isn't required, but by switching this jumper you don't have to have the printer plugged into power- the RUMBA board is powered by the USB. You can just barely see the pin over the red wire, next to the x axis stepper driver. It's pretty clearly labeled- one side says stand alone, the other usb power. Switch it to usb power so you don't have to have the printer plugged in.



Plug the usb cable in, and you should get a nice blue light on the board!



Time to install the drivers. Remember were you saved them to! If when you plugged in the usb you got a message saying unrecognized device, click it and choose either properties or update drivers. If you missed it, open the "Device Manager" in Windows, and you should see on the list something like this:



See the RUMBA xxxxxxxxxxx with the yellow mark under Other Devices? Right click and select either properties or update driver.



Go through the prompts and show it where you saved the drivers to install.





There it is! MAKE A NOTE OF WHICH COM IT SAYS IT'S USING!!!! In my case, it is set to COM 3.



Next step. Download and install the latest arduino IDE- here is the most current version at the moment: http://code.google.com/p/arduino/downloads/detail?name=arduino-1.0.3-windows.zip

When you run it it looks like this:



Next, download and install the Marlin FIRMWARE. BOTH are available here: https://github.com/ErikZalm/Marlin/tags

When you unzip it it gives you a folder full of weird files like this:



Go back to the Arduino software, and using it, open the marlin.ino file in the firmware folder you just unzipped.  The pic below shows the Repetier firmware, which should also work but will have some differences.



This is what you get. A buncha Greek. Or is that Geek?



We need to change a couple of settings. First, click on the Configuration.h tab. Scroll down and find the "#define MOTHERBOARD XXX" and change the number where the X's are (mine defaulted to 33) to 80.



Now scroll way down and find the Communication configuration section, and set the baudrate. I changed it from "#define BAUDRATE 250000" to "#define BAUDRATE 56000", cause it was recommended SOMEWHERE in the all the reading I did...



Now for the big step. You have to go to the RUMBA wiki and copy the pins.h information. Find it here: http://reprap.org/wiki/RUMBA#RUMBA_F..._Configuration Copy the entire section under Rumba Pin Configuration.

Now go back to the Arduino software, and click the pins.h tab. You may have to use the down arrow at the upper right hand corner of the screen to find it on the list.

The pins.h seems to have a crap load of different option for different boards. I just scrolled down until I found the numerical order of things (remember, we set the motherboard to 80?) so the stuff I copied I pasted between option 70 and 331.   I think you can past it between any other set of info.



Are we TOTALLY LOST YET!? Cause I sure am!

Gets a bit easier now. Once all those changes are made, with the printer hooked up just click upload. It'll take a minute or two but when it says its done, you're ready for the next step.

Download and install the Repetier SOFTWARE, available here:  http://www.repetier.com/download/
. Open the software- looks somethin like this.  PLEASE NOTE:  There is another print control software called Pronterface, available here:  http://koti.kapsi.fi/~kliment/printrun/ .  It seems great.  I like the Repetier software better but I'm having some issues getting it to finish prints... More on this later.



Now we need to set the software up to communicate with the printer. Click configure, choose printer, and this menu pops up.



You will need to change the COM to the correct one (mine was COM 3) and change the baud rate to match whatever you set it to.

Apply the settings, and you should be ready! Plug the printer in to power, and click connect. It should connect and the connect button changes to "disconnect. Scootch over to the manual control tab, and try moving axis around!!!

May seem like a lot, but now that I've done it it really wasn't that bad. There is a TON of info on the Repetier website on installing and the hows and whys of printer software, available here: http://www.repetier.com/documentatio...-installation/

Careful with that link though, my brain almost exploded...

The sad part? I still am going to have to modify the firmware to set up the thermistors (thermometers on the extruder and heated bed) AND figure out how to set it up so that BOTH z axis stepper motors work at the same time. Ug. Marching forward...


One other thing- the guys at Makers Tool Works have been awesome at helping me out with this... They have a webchat channel that anytime so far I've logged in, someone was right there to help me out. Great customer service!
Time Spent on this step: Lets call it 1 hr.
Total time so far: 14 hrs. 15 min.

Mendelmax 2.0 Wiring and Electronics

Here's where it gits a bit hairy for me...  Mechanical end of things was cake.  Wiring / electronics / software / coding... Been a while and when I did it before lets just say it wasn't my favorite thing in the world.  Got some bits made and installed. Battery died on my camera, so these were taken with my Ipad- sorry for the quality.

Made an adapter to fit the electronics board to the included mount.  The blue mount is designed for a RAMPS board, I got a RUMBA.  This is temporary, plan on printing one out of plastic when I get the printer going.



Installed. It's spacered up with washers so the contacts on the back side don't ground out.



Made some temporary mounts for the power supply since mine are missing...  Makerstoolworks.com has already shipped me the missing mounts so hopefully I will see them soon!





Turns out this piece doesn't need the t-nut, it holds itself in place with the little hook.



Which means, taking off the front plate like this was totally unnecessary.



Power supply and RUMBA board installed.





Spent some MORE time fiddling with axis trying to get them to run smoother and also running wires. Trying different things out as far as routing... still haven't settled on anything but I think I've got it figured out. I'm going to have to extend a few wires to reach the board...

Took some vids today too.



X-axis operation.



I did also run the wires from the power supply to the RUMBA board. Feel like I have a million little things to do still but I think I'm getting close. Was hoping to get more done in the time I spent on it today, but c'est la vie.

Time Spent on this step: 2 hrs.
Total time so far: 11 hrs. 45 min.

More wiring...

Had to lengthen some wires, add some ends, and route a few more pieces.





Put this cover thingy over the wires from the heated bed. No idea if that's what its for, but it looks good to me.



Got everything sorted out and routed where I think it is out of the way of moving parts.









SOOO CLOSE!



It MOVES!



Now time for software.


Time Spent on this step: 1 hr. 30 min.
Total time so far: 13 hrs. 15 min.

Man, that time sure adds up quickly!

Sorry some of the pics aren't working, I've fixed the account so they should show up shortly...