[GUIDE] How to swap your Rapide Board with a RUMBA Board (WIP)

[bolsoncerrado]

This is a WIP guide. I'll eventually update it as soon as I have time left...


Ingredients:

1.- RUMBA board (or same board with USB to MiniUSB cable)
2.- USB to MiniUSB cable (if you didnt get it on point 1)
3.- 5 (or 6) DRV8825
4.- Ask if your DRV come with heatsinks. If not, order them too.
5.- Ceramic Screwdriver (Philips Head)
6.- Yes, you need #5!
7.- Optional: Thermal Compound


Procedure:

1.- Unplug all printer cables, wires, filaments and turn it 90º over a clean flat surface.
2.- Remove the 8 x Screws on the base
3.- Take a picture of your board and wiring placement so you can keep it on your computer screen while working on the Printer.
4.- Unplug every and all wires from the Rapide board
5.- Unscrew the Board and set it aside
6a. - Optional BUT recommended: get 2 x allen screws to replace the ones in the board FAN (30mm will do) and add some spacing (using nuts) between the fan base and fan itself, so the fan rests HIGHER than before. This is because air flow should go to the new DRV8825 driver heatsinks you should be installing in next step. Note Rapide board has the DRV8825 already embeded in it, not as a sepparate module. Since RUMBA use them in module form (shield), they rest higher than before and air flow with the old fan position is too low.
6b. - Optional: Since the RUMBA board is shorter than the Rapide board, i used one of the plastic rods (left one) to attach an extra blower fan towards the Z and E heatsinks. I plug this fan to the FAN1 connector, add a jumper to turn it 12V and then in my START/END Gcode in the slicer software I instruct this fan to turn on before printing starts. This will ensure no overheating occurs on these "more busy" DRVs and extend their life.
7.- Fit your DRV8825 with the heatsinks, properly. No termic paste is required if you got them with adhesive stickers. The module is positioned in every spot in RUMBA with the chip facing inwards, towards the RUMBA.
8.- Screw the new RUMBA board using the top 2 screws (the ones closer to the printer frame).
9.- Rewire everything using the same cable order. Use the pic you took on point#3 for reference.
10.- Put the JUMPER on the USBPowered position, plug the USB cable to your computer/rasPi and turn on the Printer.
11.- Download, install and launch Arduino IDE
12.- Set Arduino to use ATMega board on the USB port of your printer and OPEN the Marlin.ino file of the Firmware Folder (pending link to modified Marlin for RUMBA on Rapide).
13.- Set up any changes you want on the Firmware settings and UPLOAD them to the RUMBA.
14.- Turn off the Printer and plug back the JUMPER to "MAINS POWER" setting. Turn on the Printer and try Connecting with your printer software. It should be working by now.
15.- Take a multimeter and set it to DC V measuring the voltage you get on the DRV (use the red pole on the potentiometer and the black one on a GND point). For X, Y set voltage to half the mV of Z and E. Refer to your DRV manufacturer as the potentiometers use to be different between manufacturers.
16.- Once all DRVs are fine tuned, re-calibrate your bed (if required) and send a test print job to see if everything works fine.

[grobbins]

A note for you as well is to try setting your extruder's DRV8825 driver to do 1/32 microstepping and then double the steps per unit for the extruder in the firmware. Theoretically this should eliminate a lot of that moire effect that we are all getting in our pritns as I have read that direct drive extruders like ours benefit from the 1/32 microstepping compared to the usual 1/16 because the 1/16 microstepping can actually cause a sort of pulsing effect with the pressure on the extruded plastic.

[bolsoncerrado]

Yes thats step#10 i still have to post about hehe

[ph03nix]

Hey Bolsoncerrado
After 2-3 Weeks I (finally) got the Rumba Board Do you have any advise beyond step 9 that might help?

[Tejase]

I finally got the schematic wiring diagram from Ethan.

RapidLogicBoard.png

[ph03nix]

Nice work
I also found this on the web as well considering the DRV8825 if anybody is interested
http://reprap.harleystudio.co.za/ste...sited-drv8825/

[bolsoncerrado]

After installing mine, they didnt happen to be "that noisy"... it just requires some finetunning... so i didnt apply the step above.

However I do recommend everyone to try avoiding GeTech (china/alixpress) DRV8825's.... If you want reliability, ask for Pololus, the originals...


https://www.pololu.com/product/2132

[bolsoncerrado]

First post updated, let me know how it goes!

[ph03nix]

Hey Bolsoncerrado,

Thanks for the Update I have chinese manufactued ones :-/ Came straight out of Hong Kong :-/
Think that will make a big difference?

[bolsoncerrado]

Well if they work on first instance, chances are they may work for a while...