Z Axis. How I Murdered PINDA - NO Regrets
Hello Fellow Tinkerers. I am new to 3d printing and so far I'm having a blast with my recently purchased MK3. I just wanted to share my findings about the well known issue of z axis consistency/pinda non pinda much talked about. Well, I had an especially hard time getting a consistent first layer. The calibration of the machine changed randomly each and every time. I had the suspect my pinda probe aka inductive proximity switch was particularly crappy. I come from electronics and furnished of oscilloscope I ventured in a quest for consistent pinda readings. Well..the sensor turned out to be even crappier than I thought. Of the signal trains in output from the sensor, the majority of the square wave pings were either missing, distorted or both.
The time response of this thing, or at least mine, is basically insufficient to get the job done. Long story short I bought a Contrinex DW-AD-502-M8 I stick it in there and...done! The machine works like a charm, it's consistent beyond my belief and it doesn't give a crap about the temperature of the bed extruder or surroundings. This is a 10-30v sensor and is easily installed in the machine. Just give the brown wire the main 12v supply from the psu and you're done. Contrary to what people might say or think the signal voltage applied to the load will be only slightly higher than pinda or at about 5.25V. The signal from the bed is picked up loud and clear every time with a repeatability of 0.1 mm according to specs but in my case I think that's even better.
Re: Z Axis. How I Murdered PINDA - NO Regrets
Is this for real?
You have the just shipped in the last two days MK3?
You had it long enough to evaluate the new PINDA, order a new one, and then replace it?
Picture was taken 12/1 at 10PM... Did you have overnight shipping?
Re: Z Axis. How I Murdered PINDA - NO Regrets
Judging by the screw of the Pinda Probe being on the left side of the Probe and not on the right side i would say its an MK2. But i am not a Prusa Version expert so... i dont realy know...
The only thing missing from that post is an affiliate link to the Contrinex new awsome probe that fixes everything 😉
Re: Z Axis. How I Murdered PINDA - NO Regrets
good to know there are better alternatives, just looked it up, its a rather expensive sensor though, 65 pounds compared to 11 euro's for the pinda
Wonder how things are with the MK3, with my mk2s its ok, if you keep the probe high enough when heating the bed.
Re: Z Axis. How I Murdered PINDA - NO Regrets
That is definitely not an MK3 fan shroud.
Re: Z Axis. How I Murdered PINDA - NO Regrets
Hello Fellow Tinkerers. ...
❗ 💡 ❗
acutally you are going to murder your RAMBo board as well !!
when you supply this probe with the 12 V and connect the npn-collector output directly to the RAMBo port, you'll sooner or later fry it if you don't add a diode (anode in direction to the RAMBo board, kathode to the probe)!
you haven't added a diode and that's why you already get the 5.25V at the output when it is connected to the RAMBo (you'll get 12V when you disconnect the connection to the port).
actually you are trying to pull up the port of the RAMBo to +12V through the internal pull up resistor of the new probe between +12V and the collector of the probe. it won't last long until the port is severely damaged.
the port of the atmega2560 already suffers because it's higher than the +5V Vcc.
so add a diode as quick as possible if you want to keep your printer alive (seems for me to be an MK2S).
about the diode: no specific type required. any standard silicium diode will do the job (like 1N4148 or 1N4001); no need to go for a shottky diode.
should have known this then, eh ?
...
I come from electronics ...
dem inscheniör is' nix zu schwör...
Re: Z Axis. How I Murdered PINDA - NO Regrets
s
dem inscheniör is' nix zu schwör...
Re: Z Axis. How I Murdered PINDA - NO Regrets
Agree with JeffJordan.
The Contrinex inductive sensor has an internal pullup resistor of 47k to supply (12V) and will properly kill your input on the RAMBo board.
The added diode protects your input from over voltage!
If the inductive proximity sensor was NPN Open Collector type, it could have been used without diode.
Have a look at my models on Printables.com 😉
Re: Z Axis. How I Murdered PINDA - NO Regrets
but I think we all have to aggree with ermanno.g about the quality of the contrinex sensors.
it's a completely different league when compared to cheap sensors like prusa's p.i.n.d.a. or some chinese LJ8A3-2-Z/BX.
that's like comparing a twizzy with an model-x.
you'll get professional quality & reliability from these swiss guys 😛 ... for a professional price 😥 .
but if you've got a numbered account at a bank like UBS, I think you don't care 
dem inscheniör is' nix zu schwör...
Re: Z Axis. How I Murdered PINDA - NO Regrets
According to the cable holder in the back, it seems to me, this is MK2S not MK3. Please confirm the type of the printer, so we can move it to the correct section.
Whenever you have issues with brand new printer, please contact our support first, before making some update on your own. In case you manage to damage surrounding parts, I don't think you will be able to get a replacement under warranty.
/ Knowledge Base
The guy behind Prusa assembly manuals...
Re: Z Axis. How I Murdered PINDA - NO Regrets
neither do I
... I don't think you will be able to get a replacement under warranty.
I'm moving it to the "improvement" section, because it's a valid information/idea about improving your printer, regardless of the modell type...
dem inscheniör is' nix zu schwör...
Re: Z Axis. How I Murdered PINDA - NO Regrets
Sorry about the confusion created...Guys...I intended MK2 😡
Yes It is correct that it would be more appropriate to put a diode in between the sensor and the Rambo input. The original pinda sensor outputs 4.8V but for the impedance involved in this case and the small currents I honestly think in the long run nothing is going to happen. Maybe I'll do it anyways just to be safe. Today I again turned the machine on, run a mesh leveling, printed from the pc. Right on the money. Cold or warm.
Re: Z Axis. How I Murdered PINDA - NO Regrets
Yes Yes. I should have suggested to stick a diode in there. Just to be on the safe side. My Bad. But I can assure you it won't harm the board anyways. There's plenty of margin.
Re: Z Axis. How I Murdered PINDA - NO Regrets
I've nuked atmega ports with less than 12V through 47kOhm... 😥
... There's plenty of margin.
dem inscheniör is' nix zu schwör...
Re: Z Axis. How I Murdered PINDA - NO Regrets
The 12 volt supply gave away that it was not a MK3 since it(MK3) is a 24 volt printer. 😆