Hello Mike Found your post interesting, what is the z axis calibration in your chart? II assume that the printer is a delta from the photo that was included. I did a number of repeatabiliy tests using the Precision Piiezo production electronics with the piezos nested in the center+/- of a rectangular bed, the piezos ranged from the smallest-10mm to the largest 40mm all mounted under bed. theby Chowa - Tech-Talk
Idris would love to try it out. What diameter disk? I can do the four that are produced. Jebk The build plate sits on the carriage held in place with screws, springs wing nuts on four corners. I will try and dig up a foto. The motor drives a belt attached to the carriage Stefby Chowa - General
I have the under bed piezo mounted at the x intersection of the bed carriage. Printer is the black widow piezo is 20mm with the plunger type.by Chowa - General
It may be appropriate to put a small drop of wd40 onto the pot, this is noted elsewhere in the instructions. I have done this as I was testing various size murata piezo disks. One point to consider is the various resonant frequencies in the xyz directions of the various printers out there and select an appropriate size disk based on its resonant frequency. In other words, if your printer rumblesby Chowa - General
Your proximity sensor should make no difference. Either it is normally closed NC or open NO. I have proximity sensors on X & Y with the piezo under bed, My preference. Using hot end version action is same. Change or verify your firmware to reflect the active low condition when activated. I have tested both on my black widow with various size piezos. Follow the instructions on setting up theby Chowa - General
One thing not being considered is that Idris already has clamping Shotky diodes on the input circuit. These clamp the piezo signal to +/- the forward voltage drop of the diodes. Putting in a bridge rectifier in advanced what is in there would be superfluous. In my under bed system I use one 20/27mm disk and the sensitivity is such that walking by on a wooden floor causes triggers. This is only anby Chowa - General
Just to answer your other questions 're the heat from the bed, in my rig you can see in the second image an aluminium covered foam blanket, dont know what kind but assume it is high temp, probably neoprene. Also assume the piezos in parallel rather than series for the Orion, Idris may shed light on that. From previous discussions parallel was used for multi sensors. Stefby Chowa - General
Those candy boxes were my first iteration for underbed using Simon's stl for his mini delta. The last image 2121.jpg is the nest of the various piezo mentioned previously. I should also mention that the cables connecting the various piezos two are shielded audio cables and the shield connected to ground at the electronics. I also tested twisted pair and twisted 3 wire. Im leaving the piezo nest aby Chowa - General
Here are some images of my rig. I should also note that double sided tape ca 1mm thick was used to attach the piezo pucks to the carrier. the work plate is attache to the carrier with spring loaded screws to the corners of the x carrier.The thick D/S tape may provide some mechanical noise isolation.by Chowa - General
I should have clarified-- the larger the piezo, the higher the output voltage per given flex. The resonant frequency may play a role in noise pickup that a specific printer may generate. To illustrate, if your printer generates noise during probing in the 2.2 kHz range, the 41 mm piezo would not be a good candidate as a sensor in my opinion. This was observed in moving x, y, z axes during my teby Chowa - General
To AlmostNeverAgain: Not familiar with your proposed design. Perhaps an under bed configuration may be more appropriate for your design if the build plate and the support carriage only moves in Y direction, the Z with effector/hot end moves vertically for your proposed design. I have tested all except the early versions of the hot end. The Orion beta, the PP20 V 1.1, the V2 with/without mountby Chowa - General
Hardy I have a number underbed with different sizes of discs. The holders are mounted to the under bed carriage to which is mounted the work plate using 4 corner springs. I have previously posted images on this thread. Stefby Chowa - General
Hardy: From the thingy image it appears that a grove mount on the hot end would work. Specifically the new Orion Regards, Stefby Chowa - General
As one of the testers, I can vouch for the features Ascribed. I am torn between the hot end mount and the underbed. Having tested both installations with multiple sizes underbed, the Orion is the way to go for those who can only use the hot end version. Great product innovation Simon, Idris and teamby Chowa - General
Which version of marlin is being used? Line numbers would be useful Stefby Chowa - General
That function needs to be enabled in firm ware. In V1.1.5 in line 725, Uncomment to enable the feature and recompile and upload. Stefby Chowa - General
Not sure myself which mode is being sensed. The bed uses 4 spring mounted adjusters With the piezo s mounted beneath the build plate . On an x shaped carriage on which are mounted the 4 different size piezos. I did post photos previously. I do have a small microphone that could be mounted on the carriage to see what the resonant frequency is. Stefby Chowa - General
Having the under bed piezo, I am not sure if the label "MICROPHONE" mode applies as the print bed is adjusted to tightly squish the plunger of the piezo. So whatever vibration from the nozzle contacting the print bed is mechanical or audio I can't say. For sure it works well! I also must say that there is an insulating blanket of a black foam (assume neoprine) covered with an aluminium foil. So wby Chowa - General
Diego: If I may comment on your last 2 lines. I do not have a delta! I have tested all sizes of the piezo sensors under bed and found that all work with the appropriate tuning. The sizes ranged from the 12mm to the gigantic 41mm. I only used one sensor mounted on the carriage holding the print bed surface at a time, although all 4 were installed, only one was tested at a time. My findings are, cby Chowa - General
Could you give the version I'd of the board? E.g. V2.xx ? I'm not aware of these boards having leds on both sides unless clones? Can you show a picture of front and back? Stefby Chowa - General
Simon, Happy you got it working. I've had limited success with it. The piezo is the best choice for me. There's more to a product no matter how good its manufactures think it is. It's called support for the product and you and your team won the goldby Chowa - General
The Schotsky diodes are already used in the input to the open amp to clamp the signal from the piezo. Perhaps a Schotsky bridge rectifier could be used? In my testing of the piezo from 12 to 41 mms diameter there is more than enough signal available to operate the circuit. In tuning the electronics, I found that the sensitivity had to be increased for the 12mm disk and decreased for the 41mm diskby Chowa - General
This is a preliminary result of my testing various size piezos with my underbed mount. The photos I have posted previously. The file is written using Notepad++. According to the data collected there seem like not much difference between the various piezos as far as Standard deviation goes. Thoughts?by Chowa - General
Here are the next set of numbers: 12mm twisted pair tuned (had to tune as o/p was low) Cold m48 with anti phase 20mm piezo twisted pair on i/p 2 m48 m48 p20 1 0.024902 0.034095 0.011717 0.017700 2 0.024 0.029 0.007 0.017 3 0.027 0.042 0.014 0.01by Chowa - General
Folks: Here are some images of the underbed sensor array (different size piezos) for testing purposes. The range from 12mm, 20mm ,27mm and 41mm. The main difference besides the size is the resonant frequency and capacitance. I found it necessary to detune the larger piezos due to excessive noise pickup. Here are several probing samples M48 and SD calculations. Note that these are only preliminarby Chowa - General
Simon As I understand the second piezo is mounted to the carriage to act as a noise source(microphone) for the main signal and is 180 out of phase with the sensor signal thus providing a noise cancelling function.and it is not mounted touching the actual build plate? Stefby Chowa - General
I crimped 2 twenties and put them into an existing holder but was not able to confirm operation of the lower piezo. These were mounted brass to brass in parallel red,red blk,blk. Connected to a V1.22 board. Is a plunger needed on both sides? Stef As an afterthought perhaps 2 of Simon's singles glued back to back?by Chowa - General
Hello I am using shielded cable with the shield grounded at the electronics only. Cable is about 40 cm. Will be testing twisted pair and 3 wire twisted with the third wire grounded at electronic ground pin. The shielded cable I scavenged from junk box works great. Stefby Chowa - General
I believe the V1.22 only has a blue led. The V2x has both red and blue . The piezo 20 has both. Checked schematics. Stefby Chowa - General
Thanks for the vid Idris.My hands are not as still as yours. The V2 is working very well on my Tevo BW Happy Holidays and the best in NY Stefby Chowa - General