Need some help configuring Marlin for a custom, rebuild Cubex Duo printer

[drock1985]

Hi,

Ive been working off and on for the last 5 months on converting an old Cubex Duo printer into a RepRap (Marlin) printer. This is mainly due to the fact that the software on the printer before was proprietary, and was limited to how/what slicers I could use. So, I gutted the electronics and replaced the mainboard with an MKS Gen L and fitted the XYZ drives with TMC2208 and the extruders with A4988. I also added a BLTouch clone (3D touch) to the system as well.

This is not my first 3D printer per say but the first time configuring from vanilla Marlin. There is a lot of extra space inside the cube this machine occupies due to the dual extruder setup and also that it has the ability to use a purge bucket (not sure about that one yet; going slowly). What I'm stuck on trying to figure out is how to best use the negative (non-print bed) space of the frame to maximize the build volume, but also get the best results when probing the bed with the probe. What settings would I need to modify in a Marlin 1.1.9 build file in order to ensure that the carriage head moves to the right positions of the bed? Also, I can't find much documentation on the 3D touch ABL sensor and wasn't sure how high to mount it from the nozzle.
20190601_121943.jpg20190601_121951.jpg
Any help would be great. I have the system itself moving and homing with a mechanical Z stop switch so that part works fine; just want to get it where I want it.

Thanks,

[maxh22]

Hi,

Ive been working off and on for the last 5 months on converting an old Cubex Duo printer into a RepRap (Marlin) printer. This is mainly due to the fact that the software on the printer before was proprietary, and was limited to how/what slicers I could use. So, I gutted the electronics and replaced the mainboard with an MKS Gen L and fitted the XYZ drives with TMC2208 and the extruders with A4988. I also added a BLTouch clone (3D touch) to the system as well.

This is not my first 3D printer per say but the first time configuring from vanilla Marlin. There is a lot of extra space inside the cube this machine occupies due to the dual extruder setup and also that it has the ability to use a purge bucket (not sure about that one yet; going slowly). What I'm stuck on trying to figure out is how to best use the negative (non-print bed) space of the frame to maximize the build volume, but also get the best results when probing the bed with the probe. What settings would I need to modify in a Marlin 1.1.9 build file in order to ensure that the carriage head moves to the right positions of the bed? Also, I can't find much documentation on the 3D touch ABL sensor and wasn't sure how high to mount it from the nozzle.
20190601_121943.jpg20190601_121951.jpg
Any help would be great. I have the system itself moving and homing with a mechanical Z stop switch so that part works fine; just want to get it where I want it.

Thanks,

Hello Drock,

I would like to know the process you did to rebuild the ciubex 3d printer. My motherboard broke and I want to rebuild it like you did.

Regards,

Max

[drock1985]

Hello Drock,

I would like to know the process you did to rebuild the ciubex 3d printer. My motherboard broke and I want to rebuild it like you did.

Regards,

Max

Hi Max,

Sorry for not replying earlier. I meant to and forgot about it until now.

I did quite a bit of trial and error work on my Cubex over the last 2 years rebuilding it the way I wanted. I basically started by gutting all the PCB boards from the extruders, motherboard, LCD, etc to get rid of all the proprietary hardware. (this was after trying to use the CUBEX firmware and a modified slicer program that worked with it. Didn't get the results I watned). After that I looked at the wiring and kept the motor wiring for the Y axis and threw away the rest as it all has non-standard connectors on them for the motors (unless you go Duet; which I think those are standard on). I also tossed the hotend assembly that the Cubex was using but decided to keep the extruders since they are part of the frame assembly for the carriage.

For the mainboard at the time when 32bit boards were in their infancy; I went with an 8bit MKS Gen L and TMC2208 drivers in standalone mode for XY and A4988 drivers for Z and the extruder (decided to only do 1 extruder on this printer; I do not like the idea of having to level the nozzles mechanically) and ran new wiring to the carriage assembly. I also installed a BLTouch clone (3D Touch) for bed leveling as I removed the springs that were worn out on the printer and used solid mounts instead. I also replaced the existing print surface with a piece of glass the same size and modeled the little alignment studs they used and glued them in place on the underside. I secure that to the frame with a binder clip from my CR-10. If I had to do any of this over again I would definitely go 32bit with the board just to have some extra serial ports and communication with the motor drivers. I decided to keep the stock Xmin and Ymax endstops that the Cubex has to get the most out of the bed space.

The hotend is a stnadard V6 clone (Triangle Labs) with an adapter I created to fit into the existing Cubex extruder. It's basically the top of the Cubex hotend chopped off and coupled to the top of a V6 hotend with a 3D printed part. The hotend cooling fan just couples to the heatsink like normal. The part cooling fans are the standard Cubex as I haven't modeled anything better yet and just have a basic fan duct on one of the fans to try and redirect the air.

The motherboard I have on the Y axis also installed an external motor stepper driver that is connected to each of the Y axis motors to keep them moving in sync. You may be able to get away with just one but with the external stepper I can provide each motor with around 1.1a of power vs. the splitter which would split that amount over both motors.

As for controlling it I just use Octoprint (since there is only 1 serial connection on this board) and a standard RepRap full graphics screen to set things like offsets and monitor prints.

Let me know if you want any more information. One thing as a tip that I learned the hard way is that you will want a good motor driver on the Z axis that will provide a lot of torque. That Nema23 motor is power hungry and needs all it can get if you do 12v like I did. a 24v system would probably run better.