Welcome! Log In Create A New Profile

Advanced

Motors necessary for a cubic meter printer based off D-bot

Posted by rodrigo 
Motors necessary for a cubic meter printer based off D-bot
July 04, 2017 12:33AM
Hi everyone,

I am building a 1 cubic meter (1x1x1m) printer for research purposes WITHOUT an extruder and heated bed. Basically I am building a gantry with XYZ movement and an acrylic bed.
The plate moves up to 50 kg up and down with 4 lead screws powered by one (or two if necessary) NEMA 23 motor with a large timing belt around them in a rectangular shape with the motor's pulley attached straight to it (simplicity is of utmost importance). An aluminum frame is moved in the x axis via 2 motors and in the Y direction with one motor mounted on this same frame.

I have come across the D-bot electrical diagram here cdn.thingiverse.com/assets/15/31/5e/8b/3c/D-Bot_Electrical_Diagram.pdf and would like to modify it for simplicity without the heating elements and LED strip.

Basically the questions are, how do I modify the diagram (do I just remove the components I won't be needing?)? Do I still need a relay if I won't use a heating bed? Do I need to change anything other than the PSU to use these more powerful motors (NEMA 23 345 Oz.)?

Thanks for helping! As a mechanical engineer, my electronics knowledge is somewhat impaired.

Hopefully I can get a reply soon, I need to order the components tomorrow (I got this research opportunity just a few days ago smileys with beer )

Edited 1 time(s). Last edit at 07/04/2017 01:13AM by rodrigo.
Attachments:
open | download - Mammoth.PNG (596.2 KB)
Re: Motors necessary for a cubic meter printer based off D-bot
July 04, 2017 01:22AM
Ok it seems I'm basically building a CNC milling kit for 3D printer use (it will eventually have some extruder, just not a melting one) so I came across this amberspyglass.co.uk/wiki/EShapeoko_Complete_Kit however, it does not use RAMPS and I do need the functionality of RAMPS later on. How could I adapt that one to my design?
Re: Motors necessary for a cubic meter printer based off D-bot
July 04, 2017 02:17AM
this controller is basically the same as a ramps, minus the mosfet and thermistors, probably running grbl firmware (processor is a Atmel Atmega 328p vs a Atmel Atmega 2560, ie 2560 has more ram and rom)


To convert all you need to do is wire the steppers to some ramps type plugs and plug into a ramps with what ever firmware you want. even can use the same driver modules.

Edited 1 time(s). Last edit at 07/04/2017 02:19AM by Dust.
Re: Motors necessary for a cubic meter printer based off D-bot
July 04, 2017 02:27AM
re larger steppers

You have to use stepper that can be driven by standard pololu modules (Pololu A4988, or Pololu DRV8825)

for anything larger, you have to use external stepper drivers, anything that uses the standard step,direction and enable can probably be used.. You simply remove the driver modules and use the step/dir and enable lines. (some external stepper drivers do require you to change the pulse width, as they can't respond to such quick pulses)

ie something like

NB this image contains an error, the +5v line needs to be plugged into vcc not +5v on that 3 pin connector

Edited 3 time(s). Last edit at 07/04/2017 02:33AM by Dust.
Re: Motors necessary for a cubic meter printer based off D-bot
July 04, 2017 06:42AM
Thanks a lot Dirt!
So I started checking the TB5650 drivers and they would be able to handle the 3A NEMAs.
If I understand right, there is nothing else that needs to be changed right? I just plug them to the ports where the Pololu drivers would have been.
Also, are they also good for 1.5A NEMA 17s? I decided for now to use those for the XY movement but still have the chance to later upgrade if necessary.
I will soon upload a fritzing diagram hoping it is correct.
Re: Motors necessary for a cubic meter printer based off D-bot
July 04, 2017 01:31PM
IMO, Arduino/RAMPS is a reasonable choice for small budget printers. But to get a good print quality from a printer with 1m^3 print volume you will have to spend a lot of money, and it doesn't make sense to use budget electronics in such systems. There are alternative (ore expensive) electronics solutions that will drive Nema 23 motors without having to use external drivers, and with additional benefits.


Delta printer calibration calculator, mini IR Z probe, and colour touch screen control panel: [escher3d.com]

Large delta printer, and other 3D printer blog postings: [miscsolutions.wordpress.com]

Full disclosure: I have a financial interest in sales of the Panel Due, Mini IR height sensor, and Duet WiFi/Duet Ethernet.
Re: Motors necessary for a cubic meter printer based off D-bot
July 04, 2017 10:49PM
24V for NEMA23 is the bare minimum voltage. Don't know, how fast you want to lift the bed, but they'd sure like to run on 36-60V driver modules.
Re: Motors necessary for a cubic meter printer based off D-bot
July 05, 2017 12:43AM
Hmm ok then, I guess I can use 24V power. This is a project for my university so more expensive parts would also be ok, however one of the goals is to try and manage it as cheaply as possible to study the feasibility of building such a printer on a tighter budget. So far the only "crazy" requirements are lifting 50 kg (which is not even that much considering the Gigabot we have here has a 60x60x.7cm aluminum printer bed) and the size, but other than that I am basically moving lightweight rollers across a longer distance which can be easily achieved with NEMA 17s even.
I have also decided to use 2 NEMA 23s to lift the bed just to make sure. As you can see, the requirements are not that high, I just have longer travel distances.
Re: Motors necessary for a cubic meter printer based off D-bot
July 05, 2017 01:23AM
So there are no RAMPS or TB6560 modules in fritzing, but basically I will use the diagram given by Dots to wire the motors, the first diagram I linked for wiring the endstops and fan, and this [reprappro.com] for wiring the second X movement motor.

Only one question remains, how do i know if my components are 24V compatible and how do >I make the change from 12V to 24V?
Re: Motors necessary for a cubic meter printer based off D-bot
July 05, 2017 06:52AM
You can run a RAMPS with 12V max. without hacking a few things. The Nema17 are OK with 12V and for the two Nema23 you can use a small DC-DC boost converter to feed the external drivers. That's cheaper than two power supplies.
Re: Motors necessary for a cubic meter printer based off D-bot
July 05, 2017 07:21AM
I'm actually using a Taurino Power with a RAMPS Premium and they should be able to handle 24V [ooznest.co.uk] . I am ordering also a 24V 350W PSU [ooznest.co.uk] which I am not totally sure is necessary as I don't know what the rated voltage VDC/phase means (the NEMA 23s are 3.6V 3A and the 17s are 1.68A).
Re: Motors necessary for a cubic meter printer based off D-bot
July 05, 2017 02:48PM
Taurino Power does indeed handle 24v as designed
Sorry, only registered users may post in this forum.

Click here to login