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Precision Piezo Z-probe Now available.

Posted by DjDemonD 
Re: Precision Piezo Z-probe Now available.
October 04, 2018 09:18AM
OMG I got it. smileys with beer

I changed the microspepping of the Z achses to 1/4 and now it works fine drinking smiley

so the frequency of the motors plays a major roll for the sensitivity of the Piezo.

for the next revision of the piezo i would recomend some kind of filter. If I am thinking right it should be a lowpass.

best regarts Kevin

ps.
I must say I realy like the idea of the piezos on a PBC as a "spring" and i took me a while to figure out not to thighten the screws to much, to allow bending of the PBC

Re: Precision Piezo Z-probe Now available.
October 04, 2018 10:12AM
Usually you want the z-axis to move as smoothly as possible, what speed and more importantly acceleration and jerk are you using for Z-probing.

The bottom clamp is designed to flex, not move when probing, it shouldn't make any difference how much friction there is on the screws. The caveat is that it the strength and flexibility of the clamp plays quite a large part in the sensitivity of the module.

The circuit includes a filter, that's most of what it does.

Idris


{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.
Re: Precision Piezo Z-probe Now available.
October 11, 2018 04:27PM
Hey
So was away for some time and now it doesnt trigger anymore -.-

The bottom clamp is printed in our PA CF pro, which is the most stiff material I know of. So I might reprint it with unfilled Nylon or PETG

the speed is 300mm/min, jerk is 12 mm/s^3 and acc is 250mm/s^2

best regarts
Kevin
Re: Precision Piezo Z-probe Now available.
October 11, 2018 04:43PM
Have you got spacers between the clamp and the PCB?

I would also suggest reducing acceleration and jerk. Personally I use very low acceleration and jerk, 5mm/s^2 and 0 jerk.

Idris


{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.
Re: Precision Piezo Z-probe Now available.
October 12, 2018 08:42AM
i have no spacer, there is nothing mentioned in the documentation..

are you sure that you have 5mm/s^2 acceleration? it seems ridicules slow.
Re: Precision Piezo Z-probe Now available.
October 12, 2018 09:17AM
There shouln't be any spacer, it looked from the picture as thought there was something between the PCB and the clamp.

5mm/s^2 is very slow but that's what I'm using, only during probing, though that's with a very different mechanical setup. I'd suggest reducing acceleration, perhaps 50mm/s^2 and reduce jerk to zero.

Idris


{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.
Re: Precision Piezo Z-probe Now available.
October 12, 2018 04:11PM
I also reduced my Z accel to 5mm/s/s when homing Z, and as a part of a macro for doing mesh leveling. I wanted to set the piezo sensors as sensitive as I could, and avoid false triggers. My Z acceleration is much more reasonable when printing, so that the whole printer doesn't need to come to a screeching halt every time it needs to lift the nozzle. (I accidentally left it there while trying to print. It wasn't pretty.) It is ridiculously low, but it sure doesn't shake the printer chassis when it starts moving the axis.


MBot3D Printer
MakerBot clone Kit from Amazon
Added heated bed.

Leadscrew self-built printer (in progress)
Duet Wifi, Precision Piezo parts
Re: Precision Piezo Z-probe Now available.
October 15, 2018 11:54AM
Quote

If I'm honest I don't think that the Orion is the cause of the problem but to eliminate it as a possibility I'm happy to send you a replacement.

I might be mis-remembering the over travel thing. Are you using the zprobe.dwell_before_probing option?

Can you PM me your order number please?

Idris

Hey, I havent heard back regarding this and unfortunately am still having issues. What is the best way to get a replacement sent out? Would emailing the website be better then private message here?
Re: Precision Piezo Z-probe Now available.
October 15, 2018 12:17PM
Huh...

I could have sworn I sent out a replacement but looking through my postage receipts I can't find a record of it. I'll send you a replacement out tomorrow but I must warn you, I've just been informed by Canada Post via Royal mail that they are expecting 4-6week delays in processing incoming mail... it's gonna take a while.

Idris


{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.
Re: Precision Piezo Z-probe Now available.
October 16, 2018 03:01AM
I may be able to get the replacement to you much faster, I've sent you a PM.

Idris


{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.
Re: Precision Piezo Z-probe Now available.
October 16, 2018 08:56AM
Due to an error on my part today I crashed the head and cracked my head mount - didn't have the spare printed I thought I had so.. one epoxy bodge later and I am printing out a new one or three!

while I print these I figured I should see what the opinion was as to my best options?

I have a Titan aero mounted to a CR-10(ish) but my current project is converting to MGN12 linear rails

as well as the current bracket I am using I am also printing out a couple of the Mount by Precision Piezo

has anyone mounted these directly to a MGN12H carriage? while I will need to design a spacer to attach the drive belts to I think height may be an issue but I wonder if the carriage is big enough to mount the bracket to or if it would need more surface area to prevent any undesirable flex(I get the bracket needs to flex the disc to work but only in one direction)? also looking at some modular carriage designs as well but not found one I like yet so that's on the back burner.

while I understand the piezo disc is more sensitive in flex than compression I currently just have it squished between the Titan aero and the bracket and this seems both extremely sensitive and rigid enough that repeatability is fantastic so I don't want to change just for the sake of it.
Re: Precision Piezo Z-probe Now available.
October 16, 2018 11:18AM
Quote
windiesel
i have no spacer, there is nothing mentioned in the documentation..

are you sure that you have 5mm/s^2 acceleration? it seems ridicules slow.

I am back with a PETG buttom clamp and it works, which is kind of strange because it works an 3 machines with our super stiff material.
Now it has acceleration of 250mm/s² Jerk 0.
I also try 1/16 with interpolation and it works as well.

best regarts and thnaks for your support.
Kevin
Re: Precision Piezo Z-probe Now available.
October 18, 2018 01:40PM
Hi!

I'm wondering if anybody has tried this with arduino or other controller?!

I've brought one of those chinese craps (I would LOVE to buy original one, but for Brazil is too expensive sad smiley a lot of TAX and other things....anyway...) and it didn't work well......so I pickup one of my arduino nano (less than $3 on ebay) and tried a simple code that just read analog and blink led on piezo touch.....and looks perfect! I dindt' tried in printer itself, but I think it will work fine. I'm planing to use just output of any pin to trigger controller probe detection (using opto-coupler or transistor would be more safe, but I don't think it's required in this case) and the best part is that this doesn't need any calibration!

About sensitive, for first test (just touching any surface) looks pretty good! The voltage reading for default reference if 0,00488v/step (10-bit ADC)......but if you want more sensitive, there's two options: use external ADC with more resolution; or just use less voltage as reference voltage (for example, 3.3v regulator, which gives me 0,00322v/step).

A litthe video of my test (the only componente used is a 1M resistor):

[www.youtube.com]
Re: Precision Piezo Z-probe Now available.
October 18, 2018 02:53PM
The output from a piezo disk will typically be from a few volts all the way up to about 90V and the current it can drive is more than sufficient to give a readable value to an analog input. Having said that, it is not a foregone conclusion that it is enough of a signal or that it is the best way to go. The circuit developed by Moriquendi filters the output from the piezo/piezos to give a usable signal while also protecting the microcontroller from excessive transient voltages. The various mechanical arrangements of the piezo disks that builders have used along with the mechanical frequency response that they give to a nozzle contact event covers a much wider range than a simple analog pin would cope with.

If the mechanical arrangement is solid (contact of the nozzle is not damped and results in a fast rising edge) then using a digital input would be preferable as the interrupt latency will be less than with an analog signal. I would suggest having a resistor in the input (about 4.7k or 10k) with two 1n4148 diodes, one between the sigal pin of the arduino and +5V with the cathode to the +5V; the other between the signal input pin and GND with the cathode to the signal pin.

Mike
Re: Precision Piezo Z-probe Now available.
October 18, 2018 03:43PM
I don't know. Using an Arduino to replace one of the PP boards is kind of...

It's not like the design isn't open-source. You could build it on some prototyping breadboard with a few dollars worth of stuff from your on-line parts supplier of choice. You may need to substitute a DIP package for the surface mount IC, but those should all be available.

I have original parts, because aside from shipping time, it's not bad at all where I live, though last weekend, I did price out what it would cost me at Digikey to make my own, and it wasn't too bad. Even better if I use a bunch of the parts that I already have in my electronics box. the ones that I'd make would be physically larger and heavier, since I'm not much good with surface mount stuff. (Means the BOM that they supply isn't much good to me, since that's all surface mount stuff, but it's not like I can't find equivalents.)

It does seem to me though that going with a well refined open source solution is going to be easier, and better than hacking together a solution and having to go through the fine-tuning and problem solving yourself. It seems that you'd be likely to need to buy some stuff from your on-line supplier to do this anyway.


MBot3D Printer
MakerBot clone Kit from Amazon
Added heated bed.

Leadscrew self-built printer (in progress)
Duet Wifi, Precision Piezo parts
Precision Piezo Andromeda announcement
November 06, 2018 08:43AM
NEW PRODUCT!

Precision Piezo Andromeda.

Designed to address some of the issues with drilled and bare piezo disks, this product brings the improved accuracy and durability of the Orion to a more adaptable, and easier to use, form factor. Designed primarily for under bed sensing but usable in any situation. Requires connection to a Precision Piezo Universal PCB or Piezo20 PCB.




Available singly or in packs of three or four.


{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.
Re: Precision Piezo Z-probe Now available.
November 08, 2018 04:19PM
I got my Orion the other day and while trying to set it up it stopped working all of a sudden.
The red LED lights up as usual and when triggered the blue LED also lights up. However, Marlin never gets the info that Z min is triggered, it always stays open.
I've tried reverting to the firmware I started with where it worked (although not all things worked, which is why I upgraded the firmware) but that does nothing.
I've also removed the Orion and plugged in the IR sensor I used before, that still works fine, so I'm pretty certain it's not an issue with the wiring or my MKS board.

The only thing I can think of is that the Orion somehow is broken, even though it's been mounted in the same place during this whole process.
Are there any other things that may cause this behavior?
Re: Precision Piezo Z-probe Now available.
November 08, 2018 04:42PM
If you turn the potentiometer does the red light go out when the blue light come on?

Idris


{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.
Re: Precision Piezo Z-probe Now available.
November 08, 2018 06:07PM
Quote
Moriquendi
If you turn the potentiometer does the red light go out when the blue light come on?

Idris

Which direction should I turn the potentiometer?
I'm a bit hesitant to turn it too much.

Edit: So I turned it counter clockwise until the blue LED was constantly on. The red LED is still on, and the sensor is still open when I run a M119.
I turned it the clockwise to further than it was initially, that didn't seem to have much of an effect. The red LED is still always on, but the sensor never reports closed.

Edited 1 time(s). Last edit at 11/08/2018 06:12PM by Akegata.
Re: Precision Piezo Z-probe Now available.
November 09, 2018 02:47AM
It sounds like your board is defective, the red led shouldn't be on at the same time as the blue led. I'll send you a replacement. Can you please PM me your address and order number?

Idris


{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.
Re: Precision Piezo Z-probe Now available.
November 09, 2018 02:57PM
The replacement is in the post, hopefully it gets to you soon.

Idris


{Precision Piezo} Accurate, repeatable, versatile z-probe plus piezo discs, endstop cables, pt100, 50w heaters.
Re: Precision Piezo Z-probe Now available.
November 09, 2018 05:28PM
Awesome, thank you!

Quote
Moriquendi
The replacement is in the post, hopefully it gets to you soon.

Idris
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