Piezo probe workaround for broken component

jrlederer

Hi all,
It's been proposed by some that there is the possibility to use alternatively available circuit boards (in this instance, dc42's mini IR board) and perform kind of modification to the board and thereafter utilize the modded board in place of the board of just accidentally busted such is the logic board for the piezo probe by DJDemonD. If this is easily doable, it would save me from needing to rebuy another piezo probe kit just for the logic board. Major simplification in my life. Thanks in advance to anyone who can direct me on how to make the miniIR board emulate the piezo probe board, even if not prefect. Just need to make it work well enough. (IIRC, it may have been Mr. Crocker himself who I might've heard make mention of his own sensor potentially being used for this exact purpose…hey, dc42, could you please help me out here? Thank you, in advance, sir.)

dc42

It should be possible to use the mini IR sensor board to read and condition the signal from a piezo, by removing some of the IR components, changing a resistor, and adding another resistor and a TVS diode. However, changes to the firmware programmed into the on-board microcontroller would also be needed.

DjDemonD

Hi Jonathan,

I've been working on using generic microcontrollers to condition signal from piezo discs. An arduino Nano ($3) and 1Mohm resistor and you can set an analogue threshold for a piezo adc reading.

Also working on a software differentiator version also.

jrlederer

Hey guys,

thanks for the response, btw, David, I appreciate it. DJD, glad you chimed in as I really should've probably PM'd you since I have been having nothing but trouble, incredibly, with this seemingly exceedingly simple device!! Making me wonder how dumb I really am after all…? Anyway, long story short, on the first day after receiving the two promo kits from you, as you may recall from my post, I mistakenly missed insulating the piezo disc from the metal of the e3d hotend which resulted in a burnt board component -- rendering 1 kit useless at the get-go.
I've got a number of projects going on currently, so decided to avoid possible further frustration and put the second (only working piezo kit) on a shelf until recently. I was meticulous with the way I handled everything (so I thought) and finally plugged everything in and powered up my machine...YAY! no magic smoke nor any signs of problems -- until I read through your manual as well as nearly the entire long thread on the topic you created and tried to research as best I could regard how to tune this using the two potentiometers .... god damned this thing -- I don't know how else to express my feeling of frustration with this bit of electronics. At no point am I able to obtain either (a) decent results (less than 2.5 as opposed to everyone else's 0.003 -- at this point I'd be thrilled to get 0.3 quite honestly, or (b) consistent, repeatable results. At this point, the f@#$king knobs on the pots have been turned so many times they turn with the current caused by speaking the vicinity. I am going mad over this.

Please help.

Kindly,
Jonathan

P.S. --> on a much brighter and lighter note, how's the new board I donated treating you?

DjDemonD

Why don't I send you a ready made, ready tuned (don't adjust it at all) Piezo20 module which I will have tested to 0.01mm accuracy when I assemble it? Free of charge.

The duet board works thank you, one of the fans mosfet seems blown but it's not a problem.

jrlederer

That sounds like a great idea (who am I to turn down such an offer, right?)…although it does leave me with a disproportionate number of piezo discuss versus controller boards why which to make use of them. Additionally, it leaves me feeling retarded with no path to anther conclusion; being the only one on earth that's ever tried your product and not been immediately successful. Here's a better idea I think:

I'll take you up on your list generous offer to send me a pre-assembled and tested unit, then in addition, toss 2 additional controller boards into the box and then let me know how much to PayPal you so hot compensated for ever. Min this way, I'll get to approach your little headache maker anew ? but if I run into similar frustrations, I can always sidestep then by moving into the pre-assembled solution. You've got my address...thanks a bunch.

DjDemonD

Ill send a PM via reprap Jonathon.

jrlederer

I thank you sir.