Extruder Pluggable Wiring Convention
Please note this is a proposal so far.
This page is here to document a proposed wiring convention to enable interchangeable extruders. The idea is that if you have a convention for your plug interface, you could readily swap out your entire extruder and replace it with another one without much effort at all. One of the key ideas behind this is to leverage existing affordable connectors that are suited to pulling the current that an extruder uses. The existing PCI-e power cabling standard can be leveraged. One can cheaply order an extension cable such as [[1]] from many sources, cut it in half and splice the wires into it between your microcontroller and your extruder, thermistor, and extruder motor. This prevents people from having to crimp these cables themselves, saving labor, and the need for a crimping tool. These plugs are very easily detachable, yet lock into each other to keep them securely connected as the extruder moves. They also are keyed so that you don't accidentally plug in the wrong component in, or plug it in the wrong direction when swapping extruders. The above PCI-e power cable has two 4-pin plugs called 41 and 42. We propose using 41 for the thermistor and heater and 42 for the extruder stepper motor. The exact wiring is as follows:
F41 (female) - reprap side - thermistor & heater
F42 (female) - reprap side - stepper motor
M41 (male) - extruder side - thermistor & heater M42 (male) - extruder side - stepper motor
LOOKING AT WHITE FEMALE F41 (Heater & Thermistor)
|-------------------------| | | | | Heater | Heater | | | | | |\ /| |------------+------------| | | | | Thermistor | Thermistor | | | | |\ /| | \-------------------------|
LOOKING AT WHITE FEMALE F42 (Stepper Motor)
(RR = RepRap ribbon cable, Mtr = Stepper Motor wires)
|-------------------------| | | | | Motor A- | Motor A+ | | | | |\ /| | |------------+------------| | | | | Motor B- | Motor B+ | | | | | |\ /| \-------------------------|
This wiring idea was first used by jkeegan and devzero in their repraps. We've posted it in the hopes that others might find it useful. If more people adopt this convention, it will enable folks to swap out components in their repraps more easily. This is especially useful as the idea of using different tooling heads on a reprap moves forwards.
- Thanks for trying to standardise things. Virtually all RepRap electronics use 4 pins in a row for the motor connectors, previously Molex KK156 types (4 mm pin spacing), now Molex KK100 types (2.54 mm pin spacing). Is there an urgent reason to change that or is it just the first thing you found at newegg? About all the RepRap shops should have proper cables available. --Traumflug 09:48, 28 October 2012 (UTC)
- The idea is that you still use whatever connections you need for your electronics (standard headers, etc), but that connects to the white female part of this locking, secure, and standard connection. Then your extruders all have connections to the black male side (I have an additional chocolate block between my hot-end wiring and the corresponding black male connector, with the stepper motor soldered straight to its black connector as that almost never needs changing. Also note that this allows you to swap extruders that require different motor directions (such as Wade's vs Greg's) with ease, as you just wire the black connector appropriately for the extruder it is connected to. Here is a video I recorded a year ago on the subject, but haven't uploaded until now (I threw it into iMovie too to add this URL to the end): RepRap Extruder Connector Standard - Jkeegan 14:20, 28 October 2012 (UTC)
