Duet 2 to upgrade Creality CR-30 ? Possible or not ?

StAnZ-007

Good morning,

I would like to know if a Duet2 Wifi card can be used to install in a Creality CR-30 printer.
The design of this printer is special because of the infinite Z axis. The X and Y axes are based on the main XY system but Z is a belt, there is no Z printing plate at all. And the X and Y axes are tilted by 45°.

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So I have some questions about this project before I start:
First of all, has anyone ever made this kind of modification to the design of this printer?

Can Duet 2 hardware be used for this type of printer? (I have 1 unused Duet2Wifi card in stock)
What about the firmware configuration for this printer?
Can the RRF configurator be used for this printer if the configuration choice is based on the XY core?
What would be the specificities to take into account for the configuration of this machine at the hardware level and at the FW level?

Thanks for your help.
Sincerely.
Stephane from France.

oliof

@StAnZ-007 X and Y are more or less standard CoreXY on this machine, You could just give Z a very high maximum axis length to make best use of this.

What's more challenging is to implement the repeat function (M303) in RepRapFirmware so that slicers emitting repeats can be used without additional post processing. You will also need to reset Z position on repeats because you can't set just the Z axis to relative mode which would be the best solution for a belt printer.

The printer also has some design limitations to take into account even if you get it to work with RRF:

The original Core driving motors tend to flex under belt tension; you might want to look at the NAK3D double shear motor replacements.
The X carriage tends to dip because using V-wheels on a 45 degree extrusion causes it to be unstable; you might want to look at replacing it with a rail mounted solution (I believe NAK3D also provides a kit for it but I am not sure).
The print head itself has precious little clearance to the surface due to the way it's mounted; using something like the "nonplanar nozzle" can help with clearance but requires a different cooling solution.
The print surface heater tends to buckle, you can shimmy it to avoid that normal v6 heater blocks seem to have just the right height.
Tuning Z height is notoriously frustrating: too close to the top surface and the belt will spring back after it's being printed on causing weird; too far and no print adhesion. Using glue or other adhesion helpers is not an option.
Tensioning the belt correctly is a bit challenging but not impossible. Unfortunately Creality swaps out belt material without announcement so what works for one printer may be inappropriate for another.

StAnZ-007

@oliof
Hi,

Thank for your information, I have check a lot of videos, tutos, and other CR-30 informations.
I will update the printer with NAK3D motors mount, allready ordered and a replacement Belt. It's same belt material seen on Ideaformer 3D Belt printers. So I hope better than the original one.
I see the linear rail kit from NAK3D, but it's expensive and not sure about quality for long time use, I will do same kind of kit by myself with HIWin linear rail.
For the nozzle system, I think I will try with the original at the bigging, and switch with orbiter system or similar after first custom step...