Understanding the Max electronics

[Toyguy]

Does anyone have any insight on why the Max gets wired up with the hot end on Heat 0 but the PEEK fan on Heat 1? Why would you not want the first extruder's PEEK fan on Fan 0 to match up with its respective hot end? Was it done to keep Fan0 open for a layer fan?

Thinking about 2 extruders in the future, it seems like it might make sense to reserve Fan0 and Fan1 for their respective extruder layer fans, allowing them to be controlled by your Gcode. Perhaps wire the PEEK fans, in parallel, to the 12V Aux Motor Out source on the Rambo since you almost always want them on anyway. You could put a toggle switch in on the front panel to turn them on and off, I suppose, if it was necessary, unless that Aux Motor Out can be controlled via an alternate M42 command with an appropriate pin number.

[Polygonhell]

Does anyone have any insight on why the Max gets wired up with the hot end on Heat 0 but the PEEK fan on Heat 1? Why would you not want the first extruder's PEEK fan on Fan 0 to match up with its respective hot end? Was it done to keep Fan0 open for a layer fan?

Thinking about 2 extruders in the future, it seems like it might make sense to reserve Fan0 and Fan1 for their respective extruder layer fans, allowing them to be controlled by your Gcode. Perhaps wire the PEEK fans, in parallel, to the 12V Aux Motor Out source on the Rambo since you almost always want them on anyway. You could put a toggle switch in on the front panel to turn them on and off, I suppose, if it was necessary, unless that Aux Motor Out can be controlled via an alternate M42 command with an appropriate pin number.

I think that's probably my fault.
All the outputs are the same regardless of the label, I did the original setup for repetier, and when I added a peek fan, my connector wouldn't reach fan1, so I used the open extruder port.

When John did the official Repetier version, he probably just copied what people were already using.

[MSURunner]

I've got my hotend cooling fan wired to the 12v output on the board. As you said, you could install a switch on there but the sharper the transition the better for printing, regardless of material, so I would rather have that fan kicking out air the entire time the printer is on.

[johnoly99]

ToyGuy,


The 'standard' for all 3d printers at the time was that heat_0 was the hotend and fan_0 was the print fan, we didn't used to have electronics and such that would support more than one hotend, one heated bed and one cooling fan, so i kept that theory, as we still sell quite a few of the BYOE (bring your own electronics) kits, so the firmware would be more 'universal' across electronics. That, combined with polygons firmware mods I had read, i just kept it that way

Yes, it could/has caused a few issues when people set up a dual extruder machine (sorry guys!) it satisfies the 99% while catching the 1% off guard. (wouldn't it be great if the rest of the world worked that way )

You can also change it in the firmware if you'd like. In configuration.h there is a COOLER_FAN_PIN that you can specify a different pin if you'd like to open that one up for a second head. Also, just having the peek fan on all the time really is the best way to do it. The new orion firmware writes that pin high in the setup, so the firmware doesn't even need to know about a COOLER_FAN_PIN anyways. It really should be on any time the machine is on, i guess thoughts being that a fan is cheap compared to frustrations from forgetting to turn it on