My 1st win cubeX converted to ramps 1.4

[bikejunky98]

Been sitting on the controller for several months while playing with KISSlicer and cubeit variations. Was getting some decent prints but tired of all the goofy firmware quirks that are out of our control causing issues with dimensional precision. Tonight I was successful in getting all steppers moving and ends stops functioning correctly along with LCD and sd reader on the arduino and ramps 1.4.

Y axis is functioning wired in parallel, but may switch in the marlin firmware to run off y/E1 depending on heat. Now for the hard part, calibration, mounting stops, fitting/wiring heated bed,fans, leds and minor detail work.

Btw, I have been able to repurpose all factory wiring, as it was installed to match up using a pair of tweezers, a few pin headers, a small chunk of perfboard, and a multimeter!!!

[Rodney Wells]

Good job    Keep us informed on your progress.  I am doing a Leapfrog conversion to Marlin. 
My CubeX runs the 3D touch operating system 5.4.2.  This is a much better option than all the Marlin stuff.  But to each there own. Still I am very interested in your first prints.
please post photos.   and again Good work. 

[bikejunky98]

Hey Rodney,

Having trouble with measuring the lead screw, do you happen to know the type/pitch?

Also, I'm getting more distance than expected in x/y as calculated. Are you running into any issues with 1/16 microstepping?

[Jetguy]

I have a full documentation of a build using a Mightyboard Rev E here so you can easily find my configs and the elusive steps per mm you are searching for

https://groups.google.com/d/msg/clone3d/5JxKWZr45xs/UUWjK6pnRIQJ

Note, the below config I swapped in GT2 belts for X and Y and 17t pulleys.- hence the 94 steps/mm

STOCK is 19t MXL 2.03mm pitch so they should be (20.3mm * 19t= 38.57mm/rev and divide that by 1 over 3200"1/16th stepping" steps/rev = 82.966035779102929738138449572206 steps/mm for STOCK pulleys and MXL belts. Again, if stock and just swapping in RAMPS, use 88.966 steps/mm for X and Y.

<axis id="x" length="275" maxfeedrate="18000" homingfeedrate="2500" stepspermm="94.11765" endstops="min"/> <!-- Pulley dia: 10.82mm / 1/8 step = 1/(10.82 * pi / 1600) -->

<axis id="y" length="275" maxfeedrate="18000" homingfeedrate="2500" stepspermm="94.11765" endstops="max"/> <!-- Pulley dia: 10.82mm / 1/8 step = 1/(10.82 * pi / 1600) -->

<axis id="z" length="235" maxfeedrate="800" homingfeedrate="800" stepspermm="533" endstops="min"/> <!-- Actual length is 157mm, we reserve ~5mm for safety. TR-8x8 Z axis = 1/(8/1600) -->

<axis id="a" length="100000" maxfeedrate="1600" stepspermm="79.6649" endstops="none"/> <!-- stepspermm is incoming filament length, see comment at bottom for explanation

[bikejunky98]

Hi jetguy,

So I've mimicked your setup on the ramps, including the dual driver for y axis and everything seems to be working correctly. I'm now working on a power board for the fans as I seem to be getting all kinds of heat off the drivers. I'm also Waiting on the identical steppers to get here, as now I I am concerned about the drivers as you commented that the stock steppers are rough on driver boards. Can you suggest a good search or link for setting the pots correctly? I seem to be getting the same reading with my multimeter no matter where I set the pots.

Thanks for all the help so far!

[bikejunky98]

UPDATE

First successful GCODE run today!

Using Pronterface and Slicer but hoping to get back to SD prints with KISSlicer eventually.

Still having issues implementing the double y stepper that JetGuy shows in his build.  I think I have an issue with the capacitor.  

working on getting the E3D V6 mounted.  Really stinks not having a printer as I would have printed the mount and several other parts that are temporary for now...

[Hugues]

Do you need some prints ? I will be happy to help you. Mp if you want

[bikejunky98]

Thanks! Trying to get by for now but I'll be in touch if I run into a must have!

Got the adapter done and fitted for the e3d v6. Finally getting the hang of making a boring tool for my mini lathe! It fits a little tight, but I don't mind the extra security of a tight fit!

I'll try to post some pics/ video tomorrow night

[Rodney Wells]

What Stepper Motor Driver step stick do you use.   I run a home made Hybrid version of marlin and BFB original system.

The standard   A4988 just could not cut.      I needed the  DRV8825 Stepper Motor Driver .  

[bikejunky98]

I'm still using ramps/ A4988 drivers. Swapped out the steppers for those described in jetguy's post also. Having trouble with the dual driver y setup but I think it's due to the 100uf/50v cap I installed on the stacked drivers.

!Just because I'm ignorant, what's the difference to the drivers u are using?

[bikejunky98]

[bikejunky98]

Some Photos.  Still a WIP but getting there!

[Rodney Wells]

Thanks for the photos That was interesting I liked your approach to some of the installs The A4988 where weak especially driving the z.   Most of the time the motor just did not step  

here is my install of the optic stop

[bikejunky98]

Finished some quick calibrations and a makeshift fan setup for the RAMPS Board.  Using KISSLICER and SD Print.  Not a big fan of Slic3r and Pronterface, but I would not have been able to set up the printer without them.  

Print is using MatterHackers Pro 1.75 PLA.  

Hoping to design some new printed mounts for the endstops this week.  Calibration for Z axis appears to be correct, but I am getting about 0.2mm less x/y travel than expected.  

<iframe width="420" height="315" src="//www.youtube.com/embed/2WNw0aOi1M8" frameborder="0" allowfullscreen></iframe>

[bikejunky98]

Hi Rodney

I'm running into the missed step issue on Z that you commented on with the a4988 driver. I ordered the driver you reccomended. In the mean time I dropped to 1/8 stepping and it seemed to help, though from all the reading, it shouldn't have.

Any reccomended settings that you could provide as a starting point?

Thanks!

[bikejunky98]

Things are up and running pretty well now with RAMPS 1.4 and KISSLICER driving from SD Card.  I am waiting on a DRV8825 from Polulo to replace the A4988 driving the Z axis.  Hopefully the new driver will allow some more fine tuning of the Z.  

For the build I used the following:

Sainsmart Ramps Kit With LCD and SD Reader and mechanical end stops

JETGUY's build setup for the steppers and the stacked A4988 Y driver

Stock wire for the most part with a customer supply board mounted to the carriage

Stock Pulleys and belts

E3D V6 hot end with custom mounting adapter shown earlier in this thread

MARLIN Firmware

As of now I have not tried to mirror the original X0,Y0 origin in the back left.  Its set in the front left same as RepRap printers.

Currently working out some custom end stop mounts to print as well as a printable 2nd extruder (temps are very well isolated with the E3D hotend.  Also looking for some longer cable that can be used to move the LCD to the same position as the original CubeX display.  

I am also attaching a copy of my Marlin settings.

 

Video of latest build : http://youtu.be/nKxzO0zWnRg

[Rodney Wells]

I found the DV8825 to be a much better board I had some good prints with it. I don't think i can help with settings as I am still using 3D systems controller But its driving the DV8825.

 I have a home made MB using the last Version of the 3D touch firmware. 5.4 .2  My Mb is Bit from her and bits from there  . lol

[bikejunky98]

Hey Rodney,

Any advice on the setup process for the dvr8825? I can't seem to get a consistent measurement for the z axis movement. The stepper appears to be missing steps no matter what I'm setting the vref to, by sound or by calculated value. It will move between .8xmm and 1.2xmm, with inconsistent cycling up and down as I move the bed to increase z height. Also I'm calculating a much higher vref (lots of humming or high pitched humming) than what the setting comes out to by sound.

2Ax0.7x0.8=1.12v
By sound .6v to .7v

Thanks

[Rodney Wells]

Have you pinned down its Stepping ration jumper pins. You do know it can do 1/32 step and its jumpers are different to you other sticks 

[bikejunky98]

Yeah, I've tried 1/32,1/16,1/8 jumper settings. All had the same issue with consistency.

[Rodney Wells]

I have tested the ramps system on a few occasions I have experienced every thing you have mentioned in your post and a few issues you haven't posted

Try This 

Just deleted my first post because the schematic was in error

[Rodney Wells]

I am in the middle of re designing the The CubeX MB on a few weeks there will be an alternative for this printer that will change a few things 

6 months i have been working on this 

On Wednesday, 27 August 2014 07:43:08 UTC+10, bikejunky98 wrote:

[bikejunky98]

Hey Rodney,

So if I understand correctly by your diagram, the drv8825 driver is being used trigger a specific voltage and amperage via the diodes, being fed from the 17vcc to the stepper coil? I'm not really good with electronics as I am self taught and just started getting my feet under me with components/ functions

[bikejunky98]

I found a max step rate setting in marlin that May have been too high. It was set to 40000. I tried to find some definitive answers on how to calculate this but came up more confused than ever. I think I'll try experimenting with lower settings when I have some time as this may be the culprit in the missed steps issue.

[Rodney Wells]

Yes that is most likely the cause.  

I would like to raise a question about the electrical system associated with the general use of boards like the drv8825 and the others.

When I installed the stepper drive boards into my CubeX mother board there was an issue with building any object that was circular.  The X and Y motors would create reverse voltages in the system and would upset each others accuracy. The diode configuration I put on the previous post would eliminate this well suppress it enough.     All coils in any system return the energy consumed on power on.  like a car ignition coils. A stepper motor is no exception.  Not as extreme but its there. 

 

I have seen this on all occasions when testing theses driver boards.  

Would you look into this and post what you find in your prints as you perfect your conversion.  

 

  Is there any body else who is using a open source Ramps or Marlin in a converted CubeX.    

[bikejunky98]

I think the maxstep setting was the culprit.  Lowering the setting to 25000 seems to have almost completely eliminated the issue.  I also slowed acceleration down to 200 and Jerk to 15.  Today I also go my PCB heated bed installed, and re-leveled the bed.  I am running my first test print now.

Heated Print Bed First run

For the Heated Bed:

Installed a 12x12 pcb heater from EBAY.  They are supposedly built in the US, which I kind of dig as everything else I have bought has been out of China.  

I cut an old window to fit as a glass plate.  Everything I have read indicates that 3mm 'ish plate glass seems to work fine as long as you don't heat unevenly and so far this seems to be working fine.  

To mount the bed, I drilled four 3mm holes in the stock bed plate.  I then covered with some Hobby Lobby .125 self adhesive cork.  The PCB goes directly on top of the cork and then I used bolts and washers to secure the plate.  

[gwece]

Hey bikejunky98,

I've been following the thread for a while to guide my CubeX conversion. I was wondering if you only changed the default_acceleration to 200 or if you also lowered the default_max_accelerations (they're 9000 by default). Movements with the parallel dual-motors in the Y-axis are much louder than with the X-axis. I'm not sure yet if it's the accelerations, micro-stepping, or my current limit that's causing it.

[Rodney Wells]

What stepper driver IC are you using?  

[bikejunky98]

I've noticed this also. Im not sure what the cause is, but I think it's due to the dual a4988 drivers. My best guess is that the dual drivers are allowing full power to each rather than spitting the voltage as normal parallel wiring would do.

Maybe one of the more knowledgable electical guys could weigh in on that...

[mon...@ecolecatholique.ca]

Did the stacked setup finally work for you and why did you install a capacitor there?

[Jetguy]

Stepper drivers are massively drawing pulses of current. Per the data sheet, every control board on the planet that drivers plug into use LOW ESR capacitors for the motor power rail as close as possible to the socket. Since we are stacking drivers, each driver needs it's own direct bulk motor capacitor.
This is critical to system stability for the driver.

[Jetguy]

Again, since these are stacked drivers, the UPPER driver does not have it's own dedicated socket and resulting nearby located bulk cap.
This system properly allows standard A4988s or newer DRV8825s to drive the dual Y motors to RATED spec.
The motors are rated at 1.68A to reach rated torque. Anything less than 1.68A per motor is LESS than rated torque and prone to skipping steps since the Y axis in a CubeX is a serious several pounds of moving mass.
Since a typical A4988 cannot safely push past 1.5A without serious heatsinking, 2 motors in parallel driven by the same drivers results in each motor only getting 1/2 of the output current.
I say again, if you max out an A4988 and push it to the breaking point of 2 Amps, each motor would only see 1A each. That's roughly 1/2 the torque below rating.
Even on a single DRV8825 rated at 2.5A MAX, two 1.68A rated motors in parallel is over that rating,resulting in less torque.

This is why we used stacked drivers and this is why we use stacked driver with a proper circuit that includes additional rail capacitance to ensure the top driver of the stack is seeing the same electrical connection that the lower driver is seeing.

[msch...@gmail.com]

Hi bikejunky98,
I've burned my factory CubeX MB while changing the hot end and wanted to upgrade the printer to a RAMPS setup...
I've been collecting bits and pieces of information from different places and just want to make sure I will have a good setup.
I'm planing on buying the Sainsmart RAMPS 1.4 board, with the Arduino Mega, 5 A4988 drivers and 3 optical endstops (http://www.sainsmart.com/3d-printing/ramps1-4/sainsmart-ramps-1-4-mega-2560-r3-a4988-opto-endstop-switch.html). I will also get their LCD with SD slot (http://www.sainsmart.com/3d-printing/ramps1-4/sainsmart-smart-controller-ramps-1-4-lcd-12864-led-turn-on-control-for-3d-print.html).
Getting a E3D V6 hot end is also on the list, but I'm not sure about the mounting adapter. Any suggestions on that?
I'm a little bit confused about the stacked Y driver... The RAMPS board seems to have 5 slots for drivers, couldn't I use two separate ones?
What about your issues with the Z axis? Did the DRV8825 driver fix it?
Finally, what power source would you recommend using? Is the stock one enough?
Thanks for any help!
Manuel

[Nate Schnase]

The 8825 helps on the Z axis but I've seen stepping issues if I stray away from optimum layer heights in my slicer.

If you aren't using a second extruder then you won't need the stacked drivers to drive the Y axis. A single extruder setup allows you to drive each y stepper with some adjustments to marlin.

Sent from my iPhone