Precision Piezo Z-probe Now available.

Here is the same mount on a delta:
Unfortunately it's running Sh*ttyware and it doesn't support probe accuracy testing.

Has anyone got a link to the 20mm piezo discs? I broke mine

they can be had from digikey [www.digikey.com]

Thanks. How can they justify £12 shipping though! RS components have them free next day delivery

Edited 1 time(s). Last edit at 10/20/2017 03:24PM by totalitarian.

rs components might be a better choice for you then [uk.rs-online.com]

Perfect thanks

Endstop cables are now back in stock, so any orders from today onwards will come with a standard 70cm endstop cable with the correct pinout for Piezo PCB.

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

executivul Amazing DXF's thanks for sharing.

Edited 1 time(s). Last edit at 10/24/2017 03:55AM by DjDemonD.

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

I see the Chinese have cloned it

Gotta love how the Chinese link directly to your sales site and Youtube for resources

Edited 4 time(s). Last edit at 10/24/2017 02:21AM by klcjr89.

Yes and I've no idea if their clone will work. However linking directly to our documents is a bit cheeky and not entirely to their advantage.

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Some more help and advice on how to get things working well.
[plus.google.com]

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Hi Simon
After a screw mount board, are you still making these? if so let me know when you have stock please.
After one for the HCE I'm about to start building

Ian

Hi Ian do you want the Piezo20 pcb on its own. I'll pm you. If you want a screw mount module ready made they're on the store, we now do a kit which is temporarily out of stock. [www.precisionpiezo.co.uk]

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

PM sent

Received my board in the mail today!

Unfortunately still, I am on my 3rd failed try to imagine a mount that fits my d-bot carriage with the Titan Aero extruder

Guess I will wait until someone smarter than me gets a good idea.

@coredump put a picture of the current mount, maybe we can think of something

Quote
executivul
@coredump put a picture of the current mount, maybe we can think of something

They usually look like one of those:

[www.thingiverse.com]
[www.thingiverse.com]

And there are some new re-designs appearing that are kinda like this

[www.thingiverse.com]

The major difficulty is not having a heatsink hanging out like the previous titan or other hotends, everything is inside that block leaving only the hotend piece out (what kills one of the common places to put the piezo).

I am printing my 4th try now to see if I get a hit, but ideas are always welcome.

Just press on the nozzle (when cold of course) and see if the vertical piece gets any flex, if it does just superglue the piezo so that it gets bent when the part flexes.
To get an idea about what I'm talking about take a look at the first photo https://www.thingiverse.com/thing:707392

I have to say these enclosed extruder/hotend designs like the one shown in coredump's 3rd link, and the Mk2/3 prusa remind me of when car engines got big plastic covers over them (to put people off from tinkering with them). So I don't think they necessarily improve your 3D printing, in fact their added, unnecessary mass may even give you ringing artefects and the like.

I've been musing over the prusa Mk2/3 hotend design for a while and seeing if we can get the piezo in there, I think we can with some minor modifications. The best idea is to modify the hotend clamp height, to allow enough space for a drilled 20 (or 16mm) piezo disc to sit on top of the hotend in the clamp, with a 3D printed spacer (or nylon washer or something similar) to insulate it. Now the overall assembly is practically the same size/shape/functionality but when the nozzle hits the bed a compressive force will be transmitted to the piezo disc.

Its not quite as sensitive as a bending force as used in the Piezo20 module, but the circuit is still quite sensitive enough to detect it. Time permitting I am going to give it a try soon.

And yes sticking a piezo (Or if not sensitive enough try 3 wired in parallel) to anything that might bend fractionally on nozzle contact should work. They are practically microphones used in this way, which nicely fits their real purpose, as low cost speakers.

Edited 3 time(s). Last edit at 10/26/2017 09:00AM by DjDemonD.

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Hey everyone,
just wanted to let you know about my experiences with the Piezo Kit board. I had it running for quite a while successfully on my VORON CoreXY printer using a custom carriage. In the beginning of this week, my probe started acting up, driving my nozzle into the bed. After a few hours of trying to re-tweak the potentiometers I was suspecting a broken piezo disc and got to work to insert a new one. My problems however, did not go away. 2 days later I noticed that the probe would sometimes (kinda) work and sometimes not at all (led was constantly illuminated no matter what I did). I went out on a limb and touched up all the solder joints by tapping them with my soldering iron/ adding some solder where I felt the pad was too dry.

This revived my board somewhat, I still haven't gotten back to the old glory, but I suspect that is due to me drilling a 4mm hole into the new disc instead of a 5mm hole, so the judgement is still out on that. Also I think my potentiometers suffered during the two days trying to get the tuning right. The sensitivity one adjusts between 0.2M and 0.4M and then suddenly jumps to 8M. I already tried the WD40 trick without much luck. Looks like a potentiometer replacement is in order.

Finally I have one suggestion for the kits and their respective manuals. All manuals, as far as I can tell, tell you to turn the potentiometers, however, they don't tell you in which direction you should turn them. It took me longer than I care to admit to figure out how to turn the sensitivity pot after I stumbled upon a post in this thread where the "higher resistance => more sensitivity" relation was mentioned. For VR2 I had to closely watch the videos on youtube to make out in which direction the potentiometer was turned. I suggest to put the turning directions into the manual too.

Other than that I want to thank anyone involved in creating this magnificent probe. I'm sure once I have fixed my oversights the probe will be back to being stellar!

Bests,
aMpeX

Edited 1 time(s). Last edit at 10/26/2017 09:57AM by aMpeX.

HI aMpex,

Thanks for your feedback. If you PM me I will send you a replacement PCB, if you would be kind enough to return the old one we can see what the failure mode is for the future, and possibly recondition it to use in-house.

The issue of potentiometers and their wear, is one that we are grappling with. We have tried larger more robust pots, but at greater expense and size per board. We are looking into a digital version at some future point with a microprocessor onboard which might remove the need for potentiometers and be auto-calibrating, or at least could be programmed/adjusted via serial.

I will amend the instructions to show which way the pots should be turned.

Regards
Simon.

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Hey Simon,

thanks for your offer. I don't know if the board will be of use to you, since I already took the soldering iron to it and, consequently, the broken solder issue is fixed (for now). If you still want to examine the board, I'll be glad to mail it to you. However, at this time, I need it on my printer (a semi-working probe is better than no probe ) so that would have to wait a bit.

I like the idea with the auto-calibration. If you need some programming muscle, please let me know (if you want a reference, I'm the guy on github that worked with teemalut to get your probing pause into Marlin. I'll also share the Voron mount I whipped up, but I have to iterate it once more to fix some issues with it.

Have a nice day!

Florian

Edited 3 time(s). Last edit at 10/26/2017 10:38AM by aMpeX.

Hi, yes thank you. Currently, Mike (Leadinglights) has been working on the microprocessor version (in assembler). So we'll see how that pans out. But might need to change this to a higher level language for a finished product or I will have no chance of being able to help people with it. Happy to drop you a new PCB, if send the old one back when you have got the replacement working that would be very helpful.

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

What uC version? What do you want to do with the uC?

Quote
executivul
What uC version? What do you want to do with the uC?

MCU is a PIC12F1830 although I am looking at a more recent PIC as well, I am using the MCU to look for the shape of a nozzle contact by looking for an unchanging signal followed by a rise where both the rate of rise and the trigger value can be programmed in. The fully evolved idea is to use it also as a mini-oscilloscope so that you can look at the signal on your printer's graphic display and tune the trigger parameters.

Mike

Quote
leadinglights

Quote
executivul
What uC version? What do you want to do with the uC?

MCU is a PIC12F1830 although I am looking at a more recent PIC as well, I am using the MCU to look for the shape of a nozzle contact by looking for an unchanging signal followed by a rise where both the rate of rise and the trigger value can be programmed in. The fully evolved idea is to use it also as a mini-oscilloscope so that you can look at the signal on your printer's graphic display and tune the trigger parameters.

Mike

I'll buy one in a heartbeat, that would be a well received board!

The one thing I was thinking about with the analog board was multiple comparators instead of the single input. Would be useful for a delta toward the outer edge where one or some of the piezos give180 degree out of phase signals.

Quote
DjDemonD

And yes sticking a piezo (Or if not sensitive enough try 3 wired in parallel) to anything that might bend fractionally on nozzle contact should work. They are practically microphones used in this way, which nicely fits their real purpose, as low cost speakers.

So, I did that and glued it to a part of my current carriage and lo and behold, I could see the blue light on the piezo 20 blinking. I started doing the calibration but wasn't getting much of a result on my duet wifi, I decided to start again from the beginning and measured the resistance between the points mentioned on the manual. It ranged from 0.8 to 0.2, but I could never find the correct knob or direction to go to get it to 0.4

It doesn't matter tho, because I am an idiot and on one of those tests I must have connected the wires inverted and fried something, because now I can turn the left pot until I get the blue light, but banging on the piezo or changing the sensitivity won't make it trigger again.

I guess it was not meant to be this time

I will keep an eye on the store so I can buy a replacement and try it again sometime.

Inverting the wires shouldn't have fried anything. The potentiometers are pretty delicate, it's just a function of their size. If you look carefully at the right hand pot you should see a flat side on the twiddly bit, turn that flat side to the bottom. This is the normal setting, it should work for almost everyone. The blue led should normally be off and flash on when triggered.

Idris

---

{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.

Quote
leadinglights

Quote
executivul
What uC version? What do you want to do with the uC?

MCU is a PIC12F1830 although I am looking at a more recent PIC as well, I am using the MCU to look for the shape of a nozzle contact by looking for an unchanging signal followed by a rise where both the rate of rise and the trigger value can be programmed in. The fully evolved idea is to use it also as a mini-oscilloscope so that you can look at the signal on your printer's graphic display and tune the trigger parameters.

Mike

You must see the timings and speed of rise, if the ADC can cope with it. I would rather use all analog/simple circuitry for it. Don't trust isolated smart chips (see BLTouch).