Underbed Piezo Mounts

thingiverse

I started following the Precision Piezo thread on RepRap forums when some people began sharing brilliant ideas about utilizing piezo disks as highly sensitive switches/probes for bed probing. DjDemonD and Moriquendi were among those who came up with innovative concepts, which eventually evolved into something called Precision Piezo (www.precisionpiezo.co.uk). I had obtained one of the earlier Piezo boards from Moriquendi and initially tried using it to mount the hotend, but I found it extremely challenging to fine-tune and the results were inconsistent. This was largely due to my own DIY solution. So, I opted for the underbed method of mounting the piezo disks, and the outcome is truly impressive. DjDemonD came up with this idea (https://www.thingiverse.com/thing:2446460). Here's a video showcasing the entire system in action while running grid leveling - you can see the mounts around 00:30 : https://photos.app.goo.gl/cz5BhU3H960tHeKa2. I designed the mounts for my 22cm diameter bed heater, and they should work with most round beds. This design is specifically intended for use with 20mm piezo disks. The model consists of three parts - the bed mount, cap, and plunger, with the piezo disk sitting between the mount and the cap. I didn't bother gluing the cap to the mount because it worked well without it, and I could adjust things as needed (e.g., flip disks). For a delta printer, you'll need three of each part, along with three M3 bolts (I used 12mm) and some T nuts. The bed rests comfortably on the plungers with a tiny gap between the mounts and the bed to prevent limiting the bed's vertical movement while probing. Make sure the plungers can easily fit through the hole in the caps. I printed this model using three outlines and three base/top layers from PETG. I would likely want to avoid using PLA if you're utilizing a heated bed, although it might still work okay.