Aluminum Heat Bed and RRP Proximity Sensor

Hi All,

I recently added the modulated IR sensor from RRP to my Prusa I3 Duet Conversion and thought I would post about my experience. It was actually a pretty simple process to get it working once I figured out how everything was supposed to be wired. Here's a look at my electronics:



Compared to the stock installation manual I had to switch the pins around on the 3 prong connector so that ground & positive were on the right pins up top. Once I made that change things started working. I am also still using a mechanical endstop for my x-axis as I wasn't really sure how the proximity sensor would work and the z-height was my primary concern.

I am using a temporary mount that has the sensor about 2mm off the bed.



I couldn't find any prior knowledge on how the sensor would work with aluminum so I was a little concerned but it seems to work just fine.
I've printed several parts and the z-height has been perfect every time so I'm crossing my fingers the days of "paper-sliding" are almost over.

I know this doesn't quite fit the Ormerod thread but I think this is the place most Duet folks hang out at and hopefully someone will find this helpful.

Nice mod! The sensor should work fine on bare aluminium, or through Kapton-on-aluminium; it's what we do with our Huxley Duo printer. It's if you put glass on it that there's a problem; the glass is invisible, so it sees the aluminium underneath! As the probe is most accurate in the 2 to 4mm range, the glass is too thick to get a good reading, so we put paper targets on top of the glass.

Ian
RepRapPro tech support

Quick tip with the RRP probe... when it gets knocked it screws up the homing, and by knocked it can include a failed print getting caught up in the head!

So, I've made this block that reinforces and protects the probe unit, its a 5 minute print that can save you a lot of wondering why your Z heights are suddenly screwy!

[www.thingiverse.com]

Very useful, thanks much!