Another Print Core Height Issue

[NewEnglandKeyboard 0]

Hey Everyone, I am having an issue levelling with a new CC print core. No matter which slot I put it in I get "Difference between detected height of both print cores exceeds realistic values". I believe it to be defective. I do have the 7.1.3.0 firmware installed and do not have this issue with my AA and BB print cores in either slot. It will stop levelling before coming close to the bed. I know the sensor boards are sensitive so maybe something defective is throwing it off.

[NewEnglandKeyboard 0]

Update,

I was trying to print Nylon 12 Carbon Fiber. When switching to PLA filament it can level. I guess the electrical conductivity of the carbon was throwing off the sensor board. Going to look for a solution

[MariMakes 199]

Hey @NewEnglandKeyboard,

 

Welcome to the Ultimaker Community 🎉

 

I'm surprised to read about this.
Doesn't Carbon Fiber also need a core change?
Leveling is heavily print core dependent 😮

Did you try any of these troubleshooting tips? 
https://support.ultimaker.com/hc/en-us/articles/360013133699-Active-leveling-errors

Please let us know if you need any more help 💪

[NewEnglandKeyboard 0]

Hey @MariMakes!

 

Thanks for responding. Definitely just seems to be an issue with the Dynamism PA12-CF filament. Just got the S3 to attempt filaments like this with the 0.4 CC print core. It will level with all my other filaments but not the carbon fiber. I know carbon is conductive so I can only assume that is what is throwing the sensor off.

Link to filament https://www.dynamism.com/material/filament/nylon-filament/dynamism-pa12-cf-black-285-500g.html

[MariMakes 199]

Hey @NewEnglandKeyboard,

Good detective work 🔍

 

If you want to know for sure you can submit a ticket on the support page and our Support Experts can analyze your logs in a special tool. https://support.ultimaker.com/hc/en-us/requests/new?ticket_form_id=360000516360

Maybe they have workarounds so you could still print with the material. 

It would be a shame if you cannot print with this cool material! 💪

[kelly67 0]

To fix a 3D printer that begins excessively high, you ought to look towards your Z-offset in your G-Code and make sure that it isn't bringing your Z-pivot excessively high without you knowing. You can change your Z-offset by straightforwardly changing the G-Code inside programming like Printer face or Pronterface  or from your slicer.

[gr5 2,196]

Most/many forms of carbon, including carbon fiber, are not conductive.  Did you check it with an ohm-meter?  It's true that nanotubes are conductive, but carbon fiber should not be.

 

I recommend you watch the leveling procedure - just the first two tests which are different.  There are 3 failure modes:

 

1) Surface detected too early.  As it does the leveling it never even touches the glass.  This indicates electrical problem such as nearby interference.

2) Surface detected too late.  The test relies on the capacitance changing.  The surface isn't detected until the glass moves down without the nozzle moving up.  Visually you see it touching the glass and still moving down more on one core than the other and it's usually obvious.  It could be the springs are too tight on the print bed or too loose on the core but this is very rare.

3) Cores are truly different heights.  This more common than you might think.  They can vary.  If you look in the log file you can see what was measured.  The cores are supposed to be 1.5mm different height nominally with an error of only 0.7mm allowed.  It could be a bit of gunk on the nozzle tip that wasn't hot enough to squish flat during the procedure.  This is extremely difficult to measure on the core itself with a micrometer as it's the height from the tip of the core to how it seats inside the print head so to the 45 degree angled area of the core just above the heat break.  So if it's issue #3 I'd just try a different core on the right core.  Or left core.

 

This below shows you how you can quickly find what the printer measured so you can see if you are failing by just 0.1mm (typical for issue #3) or by many mm.

 

 

 

[NewEnglandKeyboard 0]

Its definitely detecting too early, like a full centimeter. It will only do it when I have the carbon filament loaded. I can switch filaments without touching anything else and it works fine. Will look into pulling logs.

[gr5 2,196]

No need to pull the log if it clearly detects before touching the build plate.  The logs will just be a waste of time.

 

It's unlikely this but it takes 10 seconds to check.  Open the front door on the print head - so you can see the cores.  Part of what swings open includes the base of the print head and there is a circuit board plate there that is one side of the capacitor to detect the print bed.  There are 2 wires going to that PCB.  Tug very gently on both of them to make sure they aren't loose.  They tend to break and come loose resulting in intermittent issues.

 

Make sure there aren't any computers, cell phones, printers, things that radiate electromagnetic radiation within a half meter of the printer.

 

I suppose you may have a rare conductive filament?  Have you measured the resistance with an ohm meter?  It just seems so unlikely to me.  Even conductive filaments tend to be very high ohmage - too high to act as an antenna.  On the order of 1 million ohms per inch.  But if you are at say <10 ohms per inch then that could definitely be the issue.

 

Oh wait - maybe it has magnetic properties?  See if a magnet sticks to the filament.  Maybe that also could change how the capacitive sensor reacts.

 

[gr5 2,196]

Oh - I just looked up new england keyboard.  You are just an hour away from me.  🙂

[NewEnglandKeyboard 0]

2 hours ago, gr5 said:

No need to pull the log if it clearly detects before touching the build plate.  The logs will just be a waste of time.

 

It's unlikely this but it takes 10 seconds to check.  Open the front door on the print head - so you can see the cores.  Part of what swings open includes the base of the print head and there is a circuit board plate there that is one side of the capacitor to detect the print bed.  There are 2 wires going to that PCB.  Tug very gently on both of them to make sure they aren't loose.  They tend to break and come loose resulting in intermittent issues.

 

Make sure there aren't any computers, cell phones, printers, things that radiate electromagnetic radiation within a half meter of the printer.

 

I suppose you may have a rare conductive filament?  Have you measured the resistance with an ohm meter?  It just seems so unlikely to me.  Even conductive filaments tend to be very high ohmage - too high to act as an antenna.  On the order of 1 million ohms per inch.  But if you are at say <10 ohms per inch then that could definitely be the issue.

 

Oh wait - maybe it has magnetic properties?  See if a magnet sticks to the filament.  Maybe that also could change how the capacitive sensor reacts.

 

I did check the board since I had that issue on my ultimaker 3+ after alot of use. The sensor board wires seemed fine. I checked the conductivity of the filament and youre right. It was an insulator. A magnet did not stick to it. Im wondering if I got a defective CC print core. I do not have the packaging so I will have to see how a return could work.

[gr5 2,196]

The way it works - there is a capacitance between that plate in the print head and the metal plate of the print bed.  As the distance gets closer the capacitance increases.  So when you level, starts moving the print bed up and the capacitance slowly increases.  If the capacitance stops increasing then it assumes the nozzle hit the print bed.

 

So if it is failing before it even touches the bed - it really doesn't matter if there is any core in there at all.  Something is wrong with the sensor as it doesn't detect the capacitance increasing as the bed moves up.  This failure is usually caused by radio interference or something is faulty.  You could just disable active leveling and do it manually I suppose.  Or contact your reseller and just start replacing parts.  Usually if you replace a few boards it fixes the issue but I know sometimes they replace everything and it still fails.