Extending Mark2 to 3 heads

[foehnsturm 970]

It's time now to make a start on this project And we've got a question.

The 3rd head will be parked in the front left corner, basically using mirrored parts for the dock and the head. The printing area will stay the same, no additonal reduction. But ofc the standard electronics can't handle 3 extruders. Therefore we are looking into the possibilities of adding an extension board to multiplex the required in/outputs. However it's uncertain if this is feasible for a reasonable budget. Plan B is replacing the (old )UM2 electronics with something up to date, like Duet3D, which would offer a lot of additional benefits as well.

So, would you guys take such an upgrade, which is some € 250 extra for the electronics, into consideration at all?

[neotko 1,417]

IMO there's a list of pros and cons for using duet3d as it is

Cons

- You need to crimp 5 connectors from a normal umo+/um2 to make it work (endstops x3, 5v hotend fan and psu) All is easy but you need a crimp tool and minimum skills.

- Firmware by default doesn't have a fancy bed leveling assistant. But it has connectors for bed level sensors and has rutines to use them and auto level.

Pros

- Is silent. Like, really silent compared to an um2 board.

- It actually has 5 steppers (x,y,z,e1,e2) current um2 boards are supposed to only have 4 steppers and empty (chip-less) slot for chip 5. So much less possibilities to future mods.

- It has available an extension board to get 5 more steppers. Even servos.

- It has wifi or ethernet so you can fully control the printer on your net. It even saves last jobs on the internal SD and you can make folders and arrange the gcodes for later use.

- The steppers can handle up to 2.0A without extra cooling (um2 max used is around 1.3A and um2 boards get errors in summer at 30C+ room temp (at least I got them)). I did lots of prints this summer without any issue, but my umo+2.1.X boards did need a year ago heat sinks on the stepper chips to survive summer in Madrid.

- You can make gcode macros, so making the park/pick sequence could be a simple tast of writing a gcode that you can edit with the http access.

- No need to reflash to change stuff like esteps, size, endstops, reverse motors, change boot sequence, change minimum hotend temp for the fans to go on. Most of this stuff on um2 is only possible with the great Tinkernome firmware.

- Stepper chips don't have the Zebra effect of um2/um3 boards. They work from 16 to 256 microstepping and at 16 they have automatic interpolation to 256 for slow moves (done by the stepper chip).

- Fan/Led pwm have a real mosfet not the weak (in real max amps) of the um2 BC817-24. So it could use even stronger fans.

- Z stepper is plug ready to use 2 z screws at the same time (good for future mods).

- It allows to use 4 wire pt100 sensors. I haven't found any suitable for the olsson hotend, but they are know to be more precise. And we know that 5C more or down make a difference when using more than 1 printer and you want to have repetition. And ofc I use um2 pt100 and they work quite the same (um2 is a 3 cable pt100).

And that's all I can think atm. If I recall something else I post. Most of the stuff is quality of life. Silent, less vibrations from the steppers, better movement (microstepping interpolation), wifi upload of print files. For me the printer I have with it is the only I leave at night for the long prints since doesn't disturb my son when he sleeps. And this is with a um2 setup style, with zge and a wood umo frame. Basically the fans do more noise than the printer moves.

Edited July 22, 2017 by Guest