<p>The basic RRF board has a single Z driver which connects to two Z stepper sockets.</p>
<p>In order to individually drive two steppers, you need an optional stepper driver like in a dedicated Z2 stepper driver or a spare E1 driver to function as the second Z driver. The basic RRF board only has four drivers, so this board alone will not bring the functionality of individual driven Z steppers.</p>
<p>The extension board for support of IDEX gives access to another two stepper drivers, an X2 and a E1. Both are required for the second X-axis, so this expansion board will not give you a spare for the second Z driver.</p>
<p>With the boards you acquired you can therefore not have both dual individual driven Z screws and an additional X-axis with additional extruder (IDEX) using the current onboard drivers (including the breakout board). You need a board with at least 7 stepper drivers, but, if there are free pins available you could add an additional stepper manually in firmware.</p>

CC BY-SA 4.0
2021-10-15T12:00:45.810Z
Thank you, I'll have to look at it later to determine if there are free pins.  Do you happen to have any resources (videos/articles etc) for how I would add a stepper if there are free pins?
Joseph Crozier
CC BY-SA 4.0
2021-10-15T20:20:42.140Z
@JosephCrozier Excellent question, please post it!  On second thoughts, [this](https://3dprinting.stackexchange.com/a/10657/) might answer it. If not, post a question.
0scar
CC BY-SA 4.0
2021-10-15T06:48:48.063Z
2021-10-15T21:13:02.210Z
2021-10-15T21:13:02.210Z
0scar
<p>Long story I'll try to bullet point to speed up so bear with me:</p>
<ul>
<li>I have a heavily modded Ender 3 Pro</li>
<li>Relevant mods for this question: Control board swapped for BTT E3 RRF, Dual Z motor, BLTouch</li>
<li>Ultimately I'd love to convert the Ender 3 pro to have IDEX, probably after I make it bigger with an Ender extender kit, but it's cool if it takes a long time</li>
<li>Whether or not its easier to just build a large printer with IDEX (rather than continually changing my Ender 3) is a different question, but I just like modifying my printer.  I like learning along the way</li>
<li>Right when I got my BTT E3 RRF and my dual Z motor, I thought it'd be awesome to be able to do <code>G34</code> auto alignment, much <a href="https://www.youtube.com/watch?v=6UgT9YqY3UA" rel="nofollow noreferrer">like Teaching Tech describes in this video</a>. The BTT E3 RRF has a port for a second Z-axis motor so I thought I was good</li>
<li>Come to find out that (I believe) the second port on the board is actually just driven off the same driver, I don't believe it can be controlled separately (correct me if I'm wrong).</li>
<li>Somewhere on the internet I read that if you get the IDEX expansion board from BTT it can do that, so before I researched further, I bought one.</li>
<li>And <a href="https://www.youtube.com/watch?v=QHblq2AReqQ" rel="nofollow noreferrer">as you can see in this video from Aurora Tech, you can do indeed do <code>G34</code> with the IDEX board</a>.</li>
<li>The problem is, it looks like in that video she actually plugs the Z motor into the slot meant for the extruder motor.</li>
</ul>
<p><em><strong>Which brings me to my question:</strong></em></p>
<p>I want both. I want to be able to do <code>G34</code> but also eventually run a fully functioning IDEX. I've already bought both the BTT E3 RRF and the IDEX board....   am I out of luck?  Do you need an Octopus board or something? Or is there a way to do both with the hardware I have now?</p>

<creality-ender-3><bigtreetech>
Possible to get G34 auto align and IDEX with Ender 3 Pro and BTT E3 RRF?
Joseph Crozier
# Possible to get G34 auto align and IDEX with Ender 3 Pro and BTT E3 RRF?

(Asked by: username_0 on 2021-10-14)

Long story I'll try to bullet point to speed up so bear with me:

* I have a heavily modded Ender 3 Pro
* Relevant mods for this question: Control board swapped for BTT E3 RRF, Dual Z motor, BLTouch
* Ultimately I'd love to convert the Ender 3 pro to have IDEX, probably after I make it bigger with an Ender extender kit, but it's cool if it takes a long time
* Whether or not its easier to just build a large printer with IDEX (rather than continually changing my Ender 3) is a different question, but I just like modifying my printer. I like learning along the way
* Right when I got my BTT E3 RRF and my dual Z motor, I thought it'd be awesome to be able to do `G34` auto alignment, much [like Teaching Tech describes in this video](https://www.youtube.com/watch?v=6UgT9YqY3UA). The BTT E3 RRF has a port for a second Z-axis motor so I thought I was good
* Come to find out that (I believe) the second port on the board is actually just driven off the same driver, I don't believe it can be controlled separately (correct me if I'm wrong).
* Somewhere on the internet I read that if you get the IDEX expansion board from BTT it can do that, so before I researched further, I bought one.
* And [as you can see in this video from Aurora Tech, you can do indeed do `G34` with the IDEX board](https://www.youtube.com/watch?v=QHblq2AReqQ).
* The problem is, it looks like in that video she actually plugs the Z motor into the slot meant for the extruder motor.

***Which brings me to my question:***

I want both. I want to be able to do `G34` but also eventually run a fully functioning IDEX. I've already bought both the BTT E3 RRF and the IDEX board.... am I out of luck? Do you need an Octopus board or something? Or is there a way to do both with the hardware I have now?

**Tags:** creality-ender-3, bigtreetech

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## 1 answers

### Answer by username_1 on 2021-10-15. Score: 1 | Accepted answer

The basic RRF board has a single Z driver which connects to two Z stepper sockets.

In order to individually drive two steppers, you need an optional stepper driver like in a dedicated Z2 stepper driver or a spare E1 driver to function as the second Z driver. The basic RRF board only has four drivers, so this board alone will not bring the functionality of individual driven Z steppers.

The extension board for support of IDEX gives access to another two stepper drivers, an X2 and a E1. Both are required for the second X-axis, so this expansion board will not give you a spare for the second Z driver.

With the boards you acquired you can therefore not have both dual individual driven Z screws and an additional X-axis with additional extruder (IDEX) using the current onboard drivers (including the breakout board). You need a board with at least 7 stepper drivers, but, if there are free pins available you could add an additional stepper manually in firmware.

> **Comments:**
> **username_0**: Thank you, I'll have to look at it later to determine if there are free pins.  Do you happen to have any resources (videos/articles etc) for how I would add a stepper if there are free pins?  
> **username_1**: @JosephCrozier Excellent question, please post it!  On second thoughts, [this](https://3dprinting.stackexchange.com/a/10657/) might answer it. If not, post a question.  

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