Precision Piezo Z-probe Now available.

Looks right to me. If you can set low motor current - do so for safety. Then get the bed way down low, send a G30 and tap, make sure the bed stops moving when you tap. If that works, then send G30 and leave the nozzle to contact the bed. If that works - you're done - probe away!

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Simon Khoury

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

Did you modified the original Hypercube carriage? I'm interested in moving my piezo from the groovemount to the carriage, but I didn't have time yet to do the modifications to make room for the piezo...

Cheers

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Ismangil
Sanity check: is this configuration for Hypercube X carriage OK? I tapped the carriage and got the blue light.

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okercho
Did you modified the original Hypercube carriage? I'm interested in moving my piezo from the groovemount to the carriage, but I didn't have time yet to do the modifications to make room for the piezo...

Cheers

No, this is standard carriage. Just loosen it up a bit to insert the piezo, tighten again slightly. The board can piggyback on X endstop using a longer screw and additional nut.

Quote
DjDemonD
Looks right to me. If you can set low motor current - do so for safety. Then get the bed way down low, send a G30 and tap, make sure the bed stops moving when you tap. If that works, then send G30 and leave the nozzle to contact the bed. If that works - you're done - probe away!

The first thing I noted after configuring Marlin 1.1.8 was M119 returned Z endstop is triggered.

So I changed inverted settings to

#define Z_MIN_ENDSTOP_INVERTING false
#define Z_MIN_PROBE_ENDSTOP_INVERTING false

After that M119 reported Z min is open.

Next, G30 moved bed down a bit and then

Probe failed.

I can see blue light when bed started moving down - should I now adjust sensitivity?

What type of printer is it? It might be too sensitive yes. Show us a photo of your machine and a closeup of the piezo sensor.

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Simon Khoury

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

Quote
DjDemonD
What type of printer is it? It might be too sensitive yes. Show us a photo of your machine and a closeup of the piezo sensor.

Hypercube style

[photos.app.goo.gl]

(currently a mess, rebuilding print carriage!)

Okay so when the machine is at rest and you send m119 you get - open?
What happens if you send m119 whilst repeatedly tapping the nozzle upwards?

For tuning turn VR2 to the point where the LED just goes out. Thats the most sensitive. If you want a bit less turn VR2 slightly further and just test by tapping by hand to see what effect it has.
If its way too sensitive, when the bed lowers the vibrations through the frame trigger it.

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Simon Khoury

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

Quote
DjDemonD
Okay so when the machine is at rest and you send m119 you get - open?

Yes.

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DjDemonD
What happens if you send m119 whilst repeatedly tapping the nozzle upwards?

That's strange. It's not triggering at all, I can see the blue light almost constantly on due to my tapping yet several M119 says Z endstop still open.

Quote
DjDemonD
For tuning turn VR2 to the point where the LED just goes out. Thats the most sensitive. If you want a bit less turn VR2 slightly further and just test by tapping by hand to see what effect it has.
If its way too sensitive, when the bed lowers the vibrations through the frame trigger it.

Understood. I'll give tuning a try, and redo the whole test.

Please excuse my lack of punctuation I'm dictating this I think the problem is with end stop pull-ups being enabled if possible change your firmware configuration so that you disable end stop pull up for the Z min

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Simon Khoury

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

Quote
DjDemonD
Please excuse my lack of punctuation I'm dictating this I think the problem is with end stop pull-ups being enabled if possible change your firmware configuration so that you disable end stop pull up for the Z min

It is already disabled

//#define ENDSTOPPULLUPS // Comment this out (using // at the start of the line) to disable the endstop pullup resistors

#if DISABLED(ENDSTOPPULLUPS)
  // fine endstop settings: Individual pullups. will be ignored if ENDSTOPPULLUPS is defined
  //#define ENDSTOPPULLUP_XMAX
  //#define ENDSTOPPULLUP_YMAX
  //#define ENDSTOPPULLUP_ZMAX
  #define ENDSTOPPULLUP_XMIN
  #define ENDSTOPPULLUP_YMIN
  //#define ENDSTOPPULLUP_ZMIN
  //#define ENDSTOPPULLUP_ZMIN_PROBE
#endif

I'm a bit stumped here can you verify the signal wire between piezo pcb and your controller is unbroken? I can't think of what else is going on. Also please attach or upload/link your complete configuration.h and configuration_adv.h

Edited 1 time(s). Last edit at 01/05/2018 12:55PM by DjDemonD.

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Simon Khoury

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

Quote
DjDemonD
I'm a bit stumped here can you verify the signal wire between piezo pcb and your controller is unbroken? I can't think of what else is going on.

Signal wire continuity verified with multimeter. Also it's definitely doing something:

• If I detach signal wire M119 will show

   TRIGGERED 

• If I reattach signal wire M119 shows

   open 

Quote
DjDemonD
Also please attach or upload/link your complete configuration.h and configuration_adv.h

Here it is on [github.com]

Can we run through a couple of things to help with trouble shooting so we can try to narrow down the source of the problem.

With the printer on but not moving and the piezo board plugged in is the red led on the board lit? is the blue led lit?

If you tap the nozzle does the blue led flash?

( if the red led is lit, the blue led is unlit but flashes when you tap the nozzle then the piezo board is working and you either have a connection problem or a config problem)

You say in your last post that with nothing plugged in M119 reports a triggered z-probe, this is not what should be happening. Either the controller is expecting the wrong polarity and you need to invert that in your config or pullups are still enabled. Try inverting the z-probe signal in your config. You can check whether pullups are enabled by measuring the voltage of the signal line of the z-probe connector on your controller (ramps?) when there's nothing plugged in.

The output signal of the piezo board is very brief, it's quite difficult to catch a trigger using M119. If you need to check your setup you can either ask for a probe from near your max z-height and tap the (cold) nozzle to see whether it registers or turn VR2 slightly so that the blue led is permanently lit then call M119. You'll need to re-tune after that.

Idris

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

Because all static tests seems to be OK (board is fine, VR1 resistance normal 0.4 MOhm, etc), Marlin config seems correct, I proceeded to adjust VR2 only, decreasing sensitivity.

And it was a success! I was able to home (video), and also do G30. I haven't tried full bed leveling etc because I'm still doing a rebuild of the hotend, new extruder etc. But at least as Z endstop it is working.

One final issue was the Z home bumping, it was too slow doing the second bump, so disabled the slow speed, setting divisor to 1. I haven't been able to find a way to disable the bump entirely - I'll have to ask Marlin team about that. I also increased the bump distance from 2 mm to 5 mm, fearing too close might not achieve the tap needed for piezo activation.

So a summary for a Hypercube style X carriage, the final installation place is shown here: [photos.app.goo.gl] (previously piggybacking on X endstop was not suitable - it blocks X homing). There is an unused M3 size hole at the corner - it's there for cable ties etc. Obviously a custom place on the X carriage for the board can be designed - this is just an easy way using stock parts.

Changes to Marlin 1.1.8 running on MKS Gen L from mechanical Z endstop to Precision Piezo:

Configuration.h:

//#define ENDSTOPPULLUP_ZMIN
//#define ENDSTOPPULLUP_ZMIN_PROBE

#define Z_MIN_ENDSTOP_INVERTING false
#define Z_MIN_PROBE_ENDSTOP_INVERTING false
#define FIX_MOUNTED_PROBE
#define DELAY_BEFORE_PROBING 200
#define X_PROBE_OFFSET_FROM_EXTRUDER 0 
#define Y_PROBE_OFFSET_FROM_EXTRUDER 0
#define Z_PROBE_OFFSET_FROM_EXTRUDER 0.2

#define Z_SAFE_HOMING
#define HOMING_FEEDRATE_Z  (10*50)

Configuration_adv.h:

#define Z_HOME_BUMP_MM 5
#define HOMING_BUMP_DIVISOR { 2, 2, 1 }

Feedback on installation guide: Mention the need to check M119, z endstop is not triggered at rest.

Thank you everyone for your time and support.

I'll report further on day to day usage once my printer is back up and running.

I know I'm late to the party, but I'd be happy to be a beta tester for a Creality CR-10 machine if there are any more slots free. Would be happy to design or remix current mounts for an E3D V6 to go with it.

Hi I'm working on a CR10 idea now I have a CR10 (got it today), will test it on Monday. If it works it will be super simple to install and use (might be tricky to make but we'll figure that out). Our beta programme is currently full for now, but we might widen it up depending on how the first few units work out. Thanks for volunteering, watch this space.

Ismangil glad you got it working.

Edited 1 time(s). Last edit at 01/05/2018 06:11PM by DjDemonD.

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Simon Khoury

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

Cool beans, and congratulations. If its not one of the updated ones, consider printing a few things before you start:

1. Strain relief mod for bed heater cables
2. Adjustment wheels for bed levelling screws

And maybe doing a few other things:
1. Insulating the heated bed
2. Replacing the cooling fans (very loud!)

Thanks and happy printing

Cool I'll look into that. It's got thumb wheels on the bed adjusters, there fans are noisy-ish but not too bad.

Im sure it will get many upgrades. How do I tell what version it is? It's not the s version.. Is the s version worthwhile?

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Simon Khoury

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

From what I remember, the S version has dual z-screws, a filament sensor, and the controller comes with a bootloader installed. At the moment I think the non-S has much better value (got mine for £267), as the printer seems to work pretty well even without those upgrades - which was a big surprise to me. The thumb wheels on the default printer are ok, but you don't get much clearance to give em a twirl, the ones on Thingiverse really make bed adjustment much easier

E.g. [www.thingiverse.com]

Why advertise a product that is out of stock?

The product is not out of stock, an unforeseeable event has made DjDemonD unavailable, because of that we will be unable to fulfil any orders for a few days. Rather than allow orders to back up or leave people in limbo waiting for orders we've decided to take the shop down for the time being. If this situation last for much longer than a few days we will put contingency plans in place to bring the shop back up.

Any orders that have already been placed will be unaffected.

Please direct any support questions or other issues to me and I will do my best to help.

Idris

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

Edit to update; Idris contacted me shortly after this post, replacement is on its way.

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Hi Idris,

Ordered a kit from you guys, just putting it together now, encountered what I think is a faulty pcb.
I've sent you a message via your site, but just in case I'm missing something simple;

Vsig is around 2.5v, instead of the expected 5v (am supplying 5v in). Am not confident Ramps/arduino will consistently detect this level as a High.

VR1 will not adjust within the correct range. Once I get around 220kohm, it jumps to 11Mohm. Seems to be adjustable from ~15k->190k easily, but absolute maximum I've seen so far has been 238k - definitely less than the 400-800 range expected.

Have confirmed Vsig and voltage levels with multimeter and scope - I am definitely seeing the piezo trigger, but unless I've done something amazingly silly...

Edited 1 time(s). Last edit at 01/08/2018 02:35AM by Scott_H.

I'm following the the install parts HERE on Duet Forum and the Word online document. I have a Duet Ethernet and the V1.22 board. VR1 is tuned, VR2 however has the blue LED come one a and go off, but no red LED ever shows. I am probably at half the turns you say the screw will last, so before I go any further I need to sort some things out.
1. whats the deal with the RED LED?
2. I have it hooked to the E0 endstop ATM, I did have it on the Z-probe socket with the space between the VOLTS and the GND/TGR
3. Using my meter the + and - appear to be flipped on the board for the sensor wires.

M558 P8 I1 R0.8 X0 Y0 Z0 H5 F300 T6000 ; Set Z probe type to unmodulated, the axes for which it is used and the probe + travel speeds
G31 X0 Y0 Z-0.1 ; Set Z probe trigger value, offset and trigger height

CoreXY using a Z Max endstop, the probe only as a probe.

Edited 1 time(s). Last edit at 01/09/2018 05:36PM by Cinpro.

I believe the V1.22 only has a blue led. The V2x has both red and blue . The piezo 20 has both. Checked schematics.
Stef

Please see [www.precisionpiezo.co.uk] for the manual for v1 kit board might help.

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Simon Khoury

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

Its a bit complicated as these things have evolved, the V2 universal kit has a red light which is constantly on when tuned, and which goes off when triggered (the blue light is off when open and on when triggered) and the system uses active low/normally closed which is safer in that if its failed it should stop before diving to probe avoiding a head crash. We called the signal pin TRG on these newer devices to differentiate it from the older units which use SIG.

The V1 universal kit PCB does not have a red power indicator, just a blue LED which lights when triggered (or if you set it up with the blue LED on when open, it will go out when triggered).

The Piezo20 PCB (smaller one with one piezo connector) has a red LED for power only (its not linked to the triggering at all) and a blue LED which behaves the same as the V1 universal kit PCB above.

We will be (after I deal with the family medical problem I currently have - my father is gravely ill in France, where I am now) be moving to a V2 Piezo20 PCB, and a new product which we are currently beta testing (apologies to beta testers this will be a couple more weeks now) which will all use the same system as the V2 universal kit bringing everything into line.

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Simon Khoury

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

1. Using a small insulated screwdriver, carefully turn LEFT/VR2 adjuster- at a certain point the blue triggered LED goes out. Set it to the point just below the point where the LED goes out.

Can someone translate a little something for me? I find it a bit ambiguous. I turn the pot clockwise until the LED light goes out. Now should I keep going clockwise a little further or turn it back counterclockwise a little?

DJ all the best for you and your dad.

Keep turning a little further. You want the blue LED to be off normally, the closer VR2 is to the point where the blue LED turns on the more sensitive the board is.

Idris

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

Thanks for the kind words.

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Simon Khoury

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

Almost there, I see the LED flickers when I tap the hotend. It passes the polarity test when I push up on it. However I ran a G30 as a test and the bed didn't stop and I didn't see a reading in the DWControl. I do see it if I flick the heat block with my finger. I made my mount like the one for the Titan Aero here [www.thingiverse.com].

M558 P5 I0 R0.8 X0 Y0 Z0 H5 F300 T6000