Dual extruders

[p38nut]

I'm new to all this and have ordered a Max v2. Looking down the road what changes if any do I have to do to the Rambo board to allow it to use a 2nd extruder, if anything? I know about changes to the configuration file, and Repetier file, but do I need an extension board for the Rambo board? Will the 2nd extruder temp show up in the LCD? Sorry to sound like a newbie, but I am one. Mike

[Eaglezsoar]

I'm new to all this and have ordered a Max v2. Looking down the road what changes if any do I have to do to the Rambo board to allow it to use a 2nd extruder, if anything? I know about changes to the configuration file, and Repetier file, but do I need an extension board for the Rambo board? Will the 2nd extruder temp show up in the LCD? Sorry to sound like a newbie, but I am one. Mike

Take a look at the following topics, they should be of some help.

http://forum.seemecnc.com/viewtopic.php?f=54&t=4319
http://forum.seemecnc.com/viewtopic.php ... l+extruder

[p38nut]

Thank you. I'll read through them. Mike

[Polygonhell]

There is an error by me on the first page of the second thread, the SeeMeCNC firmware does have the same change as the one I originally set up, you need to remove the pin assignment for the Hotend fan in configuration.h and remap the heat2 pin to 7 in pins.h.
If you don't undo this change attaching a second extruder to the heat2 pin will cause it to heat at the maximum rate ignoring the thermistor reading so be careful.

I recently added a second extruder and there is more messing around in the firmware than you might initially think. Do it one step at a time and test everything piece by piece, does he second thermistor read the correct temperature (I think by default he second thermistor is incorrectly mapped to the same pin as the bed thermistor) etc etc. again not fixing this will cause the Hotend to heat in an out of control way.

Short version is be careful, a runaway Hotend can be one of the few dangerous conditions on a printer like this, the SeeMeCNC hotends have 30+ watts of heating power, they will happily burst into flames if they run away and you don't catch it, the all metal hotends ship with 40W heater cartridges, they will glow red hot before the cartridges fail, wood,paper and plastic can all be ignited by them in that state.