Corrupted gcode in SD card

[ballanux 0]

Hi all!

I finished my ultimaker yesterday and started printing immediately :cool: , the print quality is good, but sometimes the printer head starts doing weird things, like moving to another location outside the object and come back to start printing some layers above the object.

I checked the gcode in my PC and everything was right, but then, I checked the gcode in the SD card (I'm printing from the ulticontroller) and it seems corrupt at some point, which causes a couple of layers to appear in mid air!

Do you know what can be causing this?? Defective SD card? I'm using the one that came with the ulticontroller...

Thanks!

 

[illuminarti 18]

If it's specifically just the file on your SD card, I guess it could be a bad card. It might also be file corruption due to you not properly ejecting the card before you remove it from the machine, maybe?

Is the top picture the 'ok on the pc' one... or are they both from the SD card? In both pictures, something looks wrong aside from the missing bits - there's what looks like a skirt and raft floating over the top of your print... those should be at the bottom.

Perhaps if you can post the 'correct' version of the gcode, I can take a look at it, and see if it makes sense. It's also possible that your model is bad somehow, and is confusing Cura into doing odd things.

 

[ballanux 0]

The two pictures show the same corrupted file. But what's more intriguing... I have found that this corruption only occurs during the print!

I did the following:

 

1. Import the STL file in cura
   
2. Save the gcode to the SD card and copy this file to the PC
   
3. Take the card, insert it again
   
4. Read the gcode, it was OK
   
5. Print the object, then another error occurred
   
6. Stopped the print
   
7. Read the gcode in the PC, it was corrupted!
   

 

This is the gcode file view in cura after the print:

This is how the object printed:

Unfortunately I formated the card afterwards without saving the gcode, I should have made a comparison to see exactly what went wrong...

I have tried other SD card, but it doesn't get recognized by the ulticontroller (it's a 16Gb card with a partition of only 2Gb), I don't have any other 2Gb SD card...

Now I'm printing another object with the SD card write protected, I'm at 77% and everything is ok, but you never know until the end...

After this print I will try to replicate the error and see what changed in the file after printing... maybe a firmware bug?

Thanks

 

[illuminarti 18]

I doubt it's a firmware bug, because I've never heard of this happening before and surely someone would have run into it by now. So if it's really happening as you suspect, then I'd start by looking for a problem with the card, or the reader hardware... but it's certainly an odd one, so please do keep us posted as you try to track it down.

 

[Daid 306]

Did you always safely remove the card from your computer? Not doing this could irreversibly corrupt the card, it usually only corrupts a file, but it could corrupt the card forever.

(Which is why we didn't go for SD card storage on my previous job, which had very high reliability requirements)

 

[ballanux 0]

I doubt it's a firmware bug, because I've never heard of this happening before and surely someone would have run into it by now. So if it's really happening as you suspect, then I'd start by looking for a problem with the card, or the reader hardware... but it's certainly an odd one, so please do keep us posted as you try to track it down.

 

You were right!! One of the SD card reader pins in the ulticontroller is smashed down!! :mad: :mad:

Even more, it's pin 3, which is GND. As there is 2 GND pins (the other one, pin 6 is right) this causes the card to work, but being more susceptible to failure, maybe EMC related...

This will be difficult to repair... and I'm pretty sure this had to came already broken, it's very difficult to bend a single pin in the middle of the reader, so I think I will put a support ticket :-|

 

[illuminarti 18]

Pins getting/being bent in the reader seems to have been a fairly common problem lately. Definitely worth opening a ticket with support, yes.

 

[ballanux 0]

The support people replied to me very quickly, they will send me another board. I will print from the PC in the mean time.

If there are problems with this card socket maybe it's time to find another supplier for them.

If any other pin would have been bent instead of GND it would have made the SD card not to work and find the problem immediately, this was a bit unfortunate :???: