I finally got tired BL-Touch pin drops, inconsistencies and finally the bent pin! I decided to research into piezo bed leveling. I picked up an Orion Precision Piezo PCB. The journey didn't go quite a smoothly as I was hoping; mostly self-inflicted design flaws of my custom brackets since I wanted to utilize as much of the stock components as possible (e.g. fans, effector, etc...). I also didn't want to use a PTC fitting.
Added latest v15 tops and removed the excess ones including the twist top. The conical inside increased to help dampen the noise considerably which is something I was running into with previous versions. I also added Orion_Groove_Clamp_3-NUTS-v2.stl that uses M3 nuts instead of brass inserts for those that don't have them readily available. Mind you, they are not better than brass inserts, just an alternative I used since the inserts I purchased were too big and wouldn't fit next to each other in one place.
Added Orion_Groove-TLM_Top-v9-PTC-Insert.stl for those that would like to use embedded collets. I personally am trying this model now since the inside walls are too smooth on the SLA prints to hold the tubing on the main model design. I can get it to work if I slip some sandpaper around the tubing for grip but some of the "sand" falls in - not good.
Uploaded v9 versions that clean up the model (from Tinkercad to Fusion360) and offers deeper wells for the threaded nuts.
I added the following, per request:
Orion_Groove-TLM_Top-v5-M10 - threaded top for M10 PTC fitting
Orion_Groove-TLM_Top-v5-Original - simply the top of the original PP mount on the TLM mount
Orion_Groove-TLM_Top-v5-Retainer - like the original PP mount, but modified without the groove on the groove mount and taller.
You will need the following hardware:
(1) M3 x 35mm tapered head screw
(4) M3 x 16mm tapered head screws
(4) M3 x 8mm tapered head screws
(4) M3 x 12mm socket head screws (stock fan bracket screws)
(4) M3 nuts
(5) M3 x 4mm x 5mm brass inserts
Use the (4) M3 x 8mm screws to mount the fan bracket.
Heat and press the M3 nuts into place on the top bracket.
Continue the video to install the board and top bracket.
First, remove the two brass standoffs for the BL-Touch. Use the stock bracket screws to mount the hotend. Remove the two screws that hold the groove mount, they are no longer necessary.
- Delete existing heightmap.csv and config-override.g (perform a pid tune again later)
- Comment/Remove the M98,M401,M402 lines in bed.g to deploy and retract the BL-Touch
- Comment the M280 in deployprobe.g & retractprobe.g files, rename them, or delete them.
- Comment/Remove the BL-Touch commands in the config.g (M307,M558,G31)
- Add the following lines at the same location as the BL-Touch:
; Precision Piezo
M558 P5 I1 R0.6 F380 X0 Y0 Z0 A2 H3 ; Set A2 to A1 for single tap, P5 to P8 to live on the edge of sensitivity
G31 X0 Y0 Z-0.05 P100 ;
- Hit Save and Reboot.
- After machine reboots, Hit Home and adjust the sensitivity of the probe (https://www.youtube.com/watch?v=L4OCfqMVTWk)
- Let's find the Z height. Since the mount consumes some of our overall height, this will be a simpler method:
a. Create a Macro (i.e. Tiny Z Movements) with the contents:
b. Hit Home
c. Descend the hotend until a piece of paper drags underneath (I hit like -50 Z nine times, -5 a couple times, -0.5 until I can't drag the paper then +0.5 once, -0.05 until I can't drag the paper then +0.05 once, then Tiny Z Movements macro until I get a nice drag.
d. Note the current Z position (i.e. 26.72)
e. Open the config.g and update the H parameter on the M665 with CURRENT H value MINUS the value on previous step (i.e. H503 - 26.72 = H476.28)
f. Hit Save and Reboot
- Home Printer, Auto Calibrate (G32) and pray it doesn't slam into the bed. If you lack faith, have your hand on the on/off switch. :-)
- After a successful auto, do it again and look at the before and after values in the results which should be close to each other.
- Perform a mesh bed leveling (G29)
- All looks good, I recommend you perform a PID tuning twice since the config_override.g was deleted (M303 H1 S240). You can PID tune the bed if you really want to, I don't find it to be as crucial as the hotend.
M500 - save results, print!
Thanks to Mitch Mitch in the FB TLM group for providing MKS instructions. I haven't tried it, but it's a start for you.
The white wire now goes to Sig on piezo and the red (V+) and brown (GND) power it up. The yellow and black are not used.
TIP: I personally would move the yellow wire to the white position so I can use the YBR tri-wire set and remove the black and white altogether.
In the config update the zprobe.probe_pin value to 1.28! (yes, with exclamation mark).
Slow acceleration down for calibration, after a successful calibration you may put acceleration back. This lowers the chance of false triggers even after sensitivity was adjusted.
No other changes should be needed
It took a few iterations of the design to provide a nice balance of rigidity and noise dampening to set the sensitivity.
FDM is nice, but why not try SLA flavors instead?
Here's an assembled version of Orion_Groove-TLM_Top-v9-PTC-Insert.stl
** Orion_Groove-TLM_Top-v15-PTC-Insert-E3D.stl ** & **Orion_Groove-TLM_Top-v15-PTC-Insert-TL.stl** for which PTC brass collet you choose to use. I personally like the Triangle Labs one as it seems to be beefier.
This is like 1/4th the prototypes I've made. I went back to FDM parts cause the resin I was using would turn soft on me over time.