8mm Inductive Probe holder for Taz 5 w/ E3D Titan mount by taxilian

Last crawled date: 3 years ago

This is intended to be used with a side mount E3D titan extruder on the Lulzbot taz 5; it may work on the taz 6 as well, I'm not sure.
The best upgrade I ever did was to change to using an aluminum bed instead of a glass bed; this is the second best upgrade, though, which is just to add the inductive probe.
As you can see in the mockup picture this actually bolts to the extruder mount, not to the extruder plate itself, which should make it possible to swap extruders as long as the extruder you use is one which does not use the full width, such as the e3d extruder here: http://www.thingiverse.com/thing:1965603
I actually used a different mount, but it's compatible with this one and I can't find the owner of the one I used so I'm not going to post it without permission.
The probe I used is the LJ18A3-8-Z/BX 8mm Approach Sensor NPN NO: http://a.co/8DG012q
(note with these instructions: you can use +12V instead of +24V in any place I say +24V)
Something to note about this probe, and please test this yourself to verify. When connected correctly you will provide it with +24V (Brown wire) and Ground (Black wire) and then the output (blue wire) will be 3.3v when it doesn't detect anything and 0v when it does. (NOTE: I know that reading the specs this looks like it's connected wrong -- it's not. If you use the wiring that you would naively expect you will blow up your board. There is no danger as long as you hook it up right -- but I take no responsibility regardless. Always check with a voltmeter before doing something like this.
On the stock taz if you run a +24V line to the probe you can then take the blue wire on your Z endstop to the blue wire on the probe and the black wire on the endstop to the black wire on the probe (ground is shared between the Z endstop and the 24VDC system) and it should work as a drop-in replacement for your Z sensor, at least from a wiring standpoint. You do not need any voltage divider with this probe.
You will need to enable auto bed leveling in your marlin firmware, however. That's a tough topic, but I'll answer what questions I can in the comments.
Edit Apr 10, 2016: I found that the previous version of the probe holder broke off a bit too easily, so I've made a new one following the same principles as the Prusa MK2S uses. This one doesn't require the hex nuts and is actually easier to install. If you print the "small" version you'll need to use a screwdriver to pull the circle open to insert or move the probe, but it shouldn't require any hardware to hold it; if you use the "normal" version then you should use a pair of M3 screws and a pair of M3 square nuts to tighten it after positioning it where you need it. This is both more durable and also easier to adjust.
V2 also holds the probe closer to the nozzle, which should give you slightly more accurate readings