Author Topic: FrankenCube v0.1 Its ALIVE!!!  (Read 9093 times)

Dan

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FrankenCube v0.1 Its ALIVE!!!
« on: November 20, 2014, 04:12:22 am »
    Hi Folks,


    As promised, here is my instructional for the the project I've dubbed FrankenCube.  Basically, Im in the process of ripping out the guts of my Cube 2 (although these hacks will work with any Cube) and turning it into a printing monster with the Merlin Firmware, running on a Mega2560 Arduino with Ramps 1.4.  Im still working on this instructional, so be prepared for changes to be made as I figure stuff out myself.

    So why am I doing this?  Basically I got so sick of the predictable average and slow prints the Cube 2 puts out.  One thing I've noticed with the Cube is the lack of options available.  3D Systems seem to have taken a one size fits all approach to 3D printing... so while this works for many objects, it certainly doesnt work for all.  Being able to adjust print speed, retraction to prevent filament hairs, use way different filaments (like wood filament), change the print head, layer height etc is just scratching the surface of the funcationality I plan on getting out of this baby.   If you're after a full feature list, check out Slic3r, the equivalent to cubes propriety software.. Just have a poke around and check out how many different ways you can manipulate the printout.  The feature list is awesome - and thats why im doing this. 

    OK so lets get into it.

    You will need
    1x Mega 2560 Adruino Board, -$10
    4x Stepper Drivers A4988 -$12
    1x RAMPS 1.4 -$10
    1x Pack of 100 Dupont 2.55mm Wire Terminals $5
    1x Pack of 4 pin Dupont Termal Housing (You can cut these in half if you need to make 2 pin housings). $5
    1x Soldering Iron for some very basic soldering $5-500
    1x Multimeter with Resistance and Continuity Beeper $5-$500
    1x Roll of lead free Solder  $5
    1x No Clean Flux Pen $5
    1x Small Brain inc. patience $5
    1x Screw Driver
    1x Set of Hex Drivers
    1x Merlin Hotend (Purchased from eBay)
    1x AirTrippers Bowden Extruder (Any version - this is printable and will require a Nema 17 Motor. Make sure you print it BEFORE dismantling your Cube)
    1x Nema 17 high current Motor.  There are different types - get one that has high current - this is VERY important.  I got mine from Josh at Cultivate 3d in Australia
www.cultivate3d.com
1x Dupont Crimper (Not necessary, but makes the job much easier).
1x 12v Power Supply (Im using a modified computer power supply) https://www.google.com.au/webhp?sourceid=chrome-instant&rlz=1C1AVSA_enAU453AU453&ion=1&espv=2&ie=UTF-8#q=how%20to%20make%20a%2012v%20power%20supply%20from%20a%20computer%20power%20supply

OK So now we've got our shopping list out of the way, the next thing you will need is an afternoon or two. 

Overview
Half the work is already done for us by 3D Systems as we are only working on the motherboard end of this unit.  We will however have to unscrew all the covers on this thing in order to verify (preferably with a multimeter) which cable leads to what.  What we're going to do is cut off all the cables on the motherboard end of the printer and leave the other ends in place. As we identify and cut the cables, we will tag and name each set of cables to ensure we plug them into the correct place on our RAMPS 1.4 board.  With all that Arduino hardware -- Basically, our A4988 Drivers plug into the RAMPS board in 4 of the 5 driver positions (Danger DONT DO THIS YET!!!), then our RAMPS Plugs into the arduino, we screw exposed wires in to the power connector from our power supply then plug all the bits and pieces we labeled and terminated from our Cube 3D printer earlier.

Sound simple?  Yeah.

  • OK SO start by removing all visible screws from the case of your Cube 2, start at the bottom, and remove the motherboard tray from the rest of the cube.
  • Unscrew and remove the hotend cover
  • Lift the top off the motherboard tray but be careful, the LCD is connected via a ribbon cable.  Disconnect it from the motherboard, then disconnect all other cables from the motherboard
  • Remove the screws from the back of the cubes Z axis and remove the back cover
  • Remove the screws from the back of the X axis and remove the back cover.  When you remove it, disconnect the 3 fans from the wiring lume by pinching the connector.
  • Remove the 2 screws from the underside of the Y axis and wiggle the bottom cover plate out of position.   
  • Remove all screws holding the motherboard in position and vigorously remove and discard the motherboard (or keep it for parts... those voltage regs may come in handy later if you make a mistake with your wiring).
  • Now using a Multimeter to check continuity, you need to identify wiring, cut at the motherboard end, re-terminate using dupont connectors the following of your wires on your Cube.  Be sure when re-terminating these wires that you match the colour sequence on the other end of your device.  THis is particularly important for the 4x  Motors, almost everything else are 2 pin cables. 
  • Identify, Cut and Tag wires for the following
    X Motor
    Y Motor
    Z Motor
    Extruder Motor
    X End Stop
    Y Endstop
    Z Endstop
    Thermistor (Purple wires leading into the top of the hotend nozzle)
    Heater wires (thicker white wires leading to the coil around the nozzle)
    All Fan Wires (Mark them according to what they cool ie. Extruder Fan, X Fan, y fan, motherboard fan etc.) - YOU DONT NEED TO TERMINATE THESE WIRES, JUST STRIP THEM

  • Note - there are 3 wires we are NOT going to use in this project which come from the movement sensor on the extruder... THey tell the Cube when you have a Filament Flow Fail. (Unnecessary) - Identify these wires and tag them, but at least in this version of the FrankenCube, we wont be using them. 
  • Once this is done, Terminate all the wires with your Dupont Connectors.  Basically, if the set consists of 4 wires, make sure you match the colour pattern / sequence  eg Blue red black green ->Blue red black green
  • Now, time to put together your new motherboard.  Plug each of the 4 Stepper drivers into the appropriate location on your ramps 1.4 board.  MAKE SURE the little pots on the steppers are  furthest away from the power connectors (green / blue)  connectors.  If you plug them in backwards, expect them to burn and need replacing.

  • IF your Ramps 1.4 comes with a separate small resistor, wire it between R5 and R19 with the band on the resistor closest to the power connectors (it passes power from the arduino to the ramps). IF your ramps doesnt come with this resistor, dont worry, its likely already in place (see in between the connectors for the X Motor?)
  • Now connect up the end stops as pictured.  Then the motors as pictured.  Now connect the heater wires and connect the thermistor ... as pictured, then connect your power supply wires as shown.  Wire your heater wires (dont worry about polarity) to D10 on the RAMPS 1.4 board and the Hot End Fan to D9 on the RAMPS board.  With the Fan, if your polarity is incorrect, the fan will blow in the wrong direction, just reverse the polarity on D9 if that's the case.  As for all the end stops, polarity wont matter (not for the endstops in my cube anyway).


[/list]
OK.. Thats about as much as I've got tonight.  Tomorrow : Merlin Firmware.   Any questions?
_____________________________

Edit.  You may have noticed in the pictures I posted, Im no longer using the Cube direct drive extruder so I decided to post some notes on the subject. 

Basically the old Cube 2 runs on a 24v system.  This is fine for the coil based hotend the Cube 2 comes supplied with, but fails miserably when converted to 12v.  It just doesnt get hot enough to melt plastic running on 12v.  Another advantage to changing the hotend and extruder is that I was able to lighten the load on the X axis thus reducing backlash and I could pick and chose my hotend.  AS I really only want to do this once, I went for the Merlin Hotend.  It's a 12v cartridge heater hotend which has interchangeable nozzles.  THis means if I really do require finer prints, I can always change the nozzle.  The heater cartridge supplied with the Mrlin hotend heats to 230C in about 2 mins - on 12v the Cube Hotend/Extruder would get passed 205C - after 10mins. 

I recommend you download, print and assemble the Airtrippers Bowden extruder prior to dismantling the Cube, as its the only printed part I ended up requiring for this project.  Fortunately for me, I was able to rip one off a Rostock printer I'd made previously, otherwise, I'd have been up **** creek. 

THe extruder I mounted to the side of the printer (see pics) with some button head wood screws.  This seems to hold it quite well.  I used PFTE Pushfit connectors in the top of my Extruder and another in the top of my Merlin Hotend.  THe Merlin hotend does not come with a screw in connection in the top.  I had to drill a 3/8" hole in mine and use a 3/8" die to cut the thread.  Easilly done by hand with a $15 Tap from your local hardware store.  To each of the push fit connectors, I inserted about 50cm of PFTE tube to suite 1.75mm filament.  The PFTE Push fit connectors will grab permanently once you push in your tube so make sure it's cut to size first as once it goes in, it aint coming out.

To attach the hotend, I removed most of the metal parts from the X axis, grinded a slot in the end of the remaining metal bit that sticks out the bottom - big enough to "house" the PEEK part of the Merlin hotend, then used cable ties around the top and bottom of the PEEK (important - to avoid melting cable ties) and secured to whatever I could on the remaining metal part of the X axis.  Complicated sounding, but I really did fudge this - works a treat though.  Just remember, it really doesnt matter how high, low, left or right you mount your hotend - or what flavor of hotend you use - as long as it is fairly straight and doesnt move - it will be just fine.  One thing worth noting though - mout your hotend as high as possible to ensure your max print dimensions are retained as much as possible. (I lost about 10mm off my Z direction, for me, I've never pushed the limit of my Z with the Cube so I dont really care).

Check the pictures in the OneDrive Link below this post and feel free to ask questions.

« Last Edit: December 07, 2014, 04:56:14 am by Dan »

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Dan

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #1 on: November 21, 2014, 05:56:32 am »
Well it appears this is going to be more of a journey rather than a quick hack.  I've now discovered why 3D Systems used a 24v power supply for this sucker...Because the hotend wont heat beyond 215 degrees with just 12v.  Sooo this means I now need to reconsider the system. Basically I could change to a more suitable hotend for the power, OR change to a more suitable Arduino for the power. The Mega 2560 Runs on up to 20v, so... while im confident more power will sort the problem, I'd rather not run this puppy at 20v due to the fact this is a limit, not recommendation.

I've got a feeling this unit will require the addition of a J-head, cartridge style hotend which runs well on 12v, unless I can figure out how to get the Cube hotend to do more with less. 

Sigh.
   

Dan

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #2 on: November 22, 2014, 01:32:12 am »
So in the end, I trashed the shitty 3d systems hotend and changed to a Merlin J-Head with Bowden Extruder.  Reason being, Bowden is light, I can remove the weight from the X axis by using a bowden tube rather than the 3D systems direct drive.  This will make the X Axis Lighter and hopefully more accurate at high speed.  Second, this puppy runs damn good on 12v. 

Basically I removed almost all of the hotend metal parts and motor, Drilled slot in the bottom metal plate of the X axis to hold the PEEK part of the hotend, then cable tied around the PEEK to hold it nice and tightly in place. 

Ill attach some pics later.

Dan

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #3 on: November 23, 2014, 04:46:14 am »
I've finally figured out the wiring and configuration for my frankencube. The unit is printing better than it ever has.  Its quieter, faster, more accurate and much more flexible.  Can't post any pics for the next few days because our internet at home took a lightning strike.  I'll post a copy of the customised marlin firmware as soon as my home internet comes back online along with some revised wiring details and further instructions.

fritshgl

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #4 on: November 26, 2014, 01:01:00 pm »
Hello Dan,
I am very happy with your information because i am thinking about doing the same with my cube 3d 2nd gen. printer.
 About a year ago i did build a 3d printer (http://www.thingiverse.com/make:72807) with minitronics Electronics (reprapworld.com).
So i am thinking of using mintronics because a have some experience  with that and not with adruino.
I would very much like more information about the marlin firmware and the wiring.
I assume you want to print with ABS because you mention that you need a higher temperature than 215 C?.
So thanks again and Kind Regards,
Frits (The Netherlands)

Dan

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #5 on: December 05, 2014, 04:55:20 am »
Hi Fritz,

Ill try to make this as simple as possible...  Dont waste your time with the cube as is.  If you're thinking about it  - leap right in.  I've had to make quite a few changes to the chassis, heaps to the electronics etc, but geez was it worth it.  Print quality to so much superior to what the Cube 2 could do as it was purchased.  Im so happy with the results.  Here's a pic of the nearly finished product.  https://onedrive.live.com/embed?cid=3816C66A7D7D18AA&resid=3816C66A7D7D18AA%212282&authkey=AGFO2y4xry0xM0I

Basically, from a wiring perspective, here's how it goes.  Everything wired as a normal Marlin setup would be, however :   X and Y endstops MUST be wired to the MIN endstop location on RAMPS 1.4 and the Z must be wired to the Z MAX endstop on RAMPS.  Fans (I've used 5) I reused from the ones I pulled out of the original Cube Setup.  I used Cable ties to loosely connect the fans to each motor, one around the girth of the motor, then 2 more connecting the fan to the girth cabletie.  Then just wired all of them in Parallel to D9 on the RAMPS.  Most important is the fan over the RAMPS.  If you dont use the fan, your stepper drivers will get too hot and skip steps and the worst possible time.  Trust me, just wire it in.  As for Firmware, here is the modified firmware im using.  The solution in the end was simple, but getting there took days of screwing around.  There was no manual or help anywhere to do this, so I had to experiment a lot. 

https://onedrive.live.com/embed?cid=3816C66A7D7D18AA&resid=3816C66A7D7D18AA%212281&authkey=AHF_eUTC465Z8m8

If anyone has any questions, or requires detailed pics, please let me know. 

By the way, that first one drive link will be where I post pics of this project.  Check back often as I'll add more pics as requested and as the project develops.

Regards
Dan
« Last Edit: December 05, 2014, 05:14:55 am by Dan »

Dan

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #6 on: December 05, 2014, 05:23:28 am »
Did I mention how quiet this unit is with the new electronics.  Basically, from what i can tell, the Cube 2 as is had drivers that were way overdriven (too much amps to motors).  THis created vibrations along the Y axis particularly in my unit and made it incredibly noisy.  With the Frankencube, I was able to quieten the whole setup by dialing down the current to XYZ motors and adding a fan to each of the motors as well as the electronics.  I now have whisper quiet, reliable operation.  The Extruder however has full current applied, but as it moves generally so much slower than the other motors, the noise is minimal, even with high current.


fritshgl

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #7 on: December 06, 2014, 06:22:14 am »
Hi Dan,
Thanks for your information. I will follow your advices.
I will let you know how i am getting along with the project.
Also my cube was very noisy, one of my reasons to change the electronics to open source.

Kind Regards,

Frits

Dan

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #8 on: December 07, 2014, 04:12:51 am »
You dont *have* to change the electronics to OS to make the motors quieter, but you DO need to strap a fan on the back of each of the stepper drivers and reduce the current by turning the 3 pots on the main board about 1/4 turn anticlockwise.  Still there are a billion other reasons to do so - print quality would be the biggest for me. 

I figured out the reason the steppers are so noisy is because they are WAY overdriven.  The current I ended up with was about half of the original.  A rough way to measure this is to use a Multimeter - place one pole on a common earth (Black wire from power supply) and the other in the center of the pot you are testing.  A typical value should be between .1 - 2.5v (if the stepper allows).   With the A4988 drivers im currently using, I have mine set to about .2v for each Axis and .95 for the extruder.  THese figures would not be achievable without cooling on each of the Stepper Motors AND the electronics themselves.  I have a fan (cable tied of course) right over the stepper drivers. This printer is now one of the quietest i've heard.

« Last Edit: December 07, 2014, 04:51:07 am by Dan »

mystuno

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #9 on: December 17, 2014, 02:55:15 am »
Great project! Looking forward to see your results on this beast!

I would love to hack my Cube Gen1 in some near future. I'm frustrated with this machine as well, lack of parameters to play with.

Thanks for sharing!

fritshgl

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #10 on: December 17, 2014, 02:55:40 pm »
Hello  Dan

I did build the minitronics Electronics in my cube. At the moment i am testing the x,y,z movements and the extruder. With regard to the thermistor of the extruder i have the impression that it is a 200k thermistor and not a 100k thermistor. Because with a 200k thermistor in the firmware the temperature at room temp is 22 Celcius, with a 100k thermistor only 6 C.  In your firmware you have the 100k thermistor. I think your 100k thermistor is the one of your new hotent. Is that right.
Beside that  the max temp i can reach with 12 volt is +/- 150 C. So i wil use a relais to supply the hotend with 24 volt (the original powersupply).

Kind Regards,

Frits

Dan

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #11 on: December 18, 2014, 03:39:58 am »
Correct and Correct again.  100K is for the new hotend, the old thermister went with the old hotend.  Does minitronics accept 24v? I know my Mega 2560 /RAMPS is max 12.  From memory I also used the 200K setting while testing the old hotend.
« Last Edit: December 18, 2014, 03:43:39 am by Dan »

fritshgl

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #12 on: December 18, 2014, 05:21:28 am »
Hello Dan,

I think the minitronics can be used with 24 volt. But because you wrote "this puppy runs damn good on 12v" i bought a 12 volt power supply.
So i will connect the hotend power of the minitronics to a 12 volt relay. This relay wil switch the 24 volt of the original cube power supply to the hotend.

Frits

Dan

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #13 on: December 18, 2014, 05:45:57 am »
I can see V1.1 runs on 12v max.  according to specs I read on ebay listing for the board.  Would it not be easier to change the hotend?  - then you have the benefit of reducing weight on the X axis, allowing greater speeds with less backlash due to lower inertia.
   

fritshgl

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Re: FrankenCube v0.1 Its ALIVE!!!
« Reply #14 on: December 22, 2014, 06:16:17 am »
Hello Dan,

Switching 24 volt to the extruder with a relay was not a good idea. A lot of noise from de relay.
So I followed your suggestion end discovered that the minitronics can also run with up to 24 volt.
Now I am running the electronics with 19 volt, and a separate 12 volt supply for the cooling fans.
The heating up of the extruder is now really fast. So a very good suggestion from you. Thanks again.

Frits