Failure States

[kcel 11]

Hi,

 

I've had a couple interesting failures in the last week, and I don't think the printer handles either one entirely correctly.  I'm hoping some updates to the firmware can be made to make the printers a little more idiot proof:

 

1.  A couple of times I've received an ER18 error indicating an inability to communicate with the print head.  This error has been resolved just by cycling the printer.  The problem is when the error has occurred it happened mid-print, leaving the nozzle in close contact with the print.  The cooling fans were still on so I think it might be fine but I'm paranoid about what might happen if that failure were to occur when I'm not home.  When ER18 error occurs I wondering if the bed should lower to make sure the print isn't anywhere near the nozzle.   

 

2.  My printer lost power during a print.  User error, no worries.  When I restarted the bed stayed in it's raised position, again with the nozzle too close to the print.  It asked me to remove the print, which was hard because the nozzle was in the way.  So I confirmed that I removed it, then went to the build plate menu and lowered the build plate and removed the print and cleaned up the bed.  Then, suddenly, the build plate raised up and it started to prep things to do the print again.  Bonus points for keeping the print in the queue, but I think it should have asked me if I wanted to start the print again before doing anything.  I had to confirm that I removed the print in order to access the controls to remove the print.  If I had not removed the print, or had some issue removing it, bad things would have happened.  So again, on restart of the printer after a failure, it should lower the build plate and it should make sure to ask for confirmation before restarting the queued print.

 

Not earth shattering problems, fairly easily resolved, but the printer could be a bit smarter about it.

 

Cheers!

[kmanstudios 1,120]

Regarding #1:

 

You should remove the back plate at the top rear of the printhead and make sure the connector is fully seated into the printhead. It can come a bit loose and this will help resolve that issue. This is a bit more elaborate in explanation.

@fbrc8-erin did a great job of explaining it.  (It seems the tagging did not work like it should)

If you are printing very hot and keeping the heat in, it can help make the plastics a bit loose and need to be reset.

 

Regarding #2:

 

Yeah, seconding that one. Especially, as you state, you are trying to clean things up and it just goes about its business.

[kcel 11]

2 hours ago, kmanstudios said:

You should remove the back plate at the top rear of the printhead and make sure the connector is fully seated into the printhead. It can come a bit loose and this will help resolve that issue. This is a bit more elaborate in explanation.

 

Ah, cool.  Thanks for that.

[CarloK 204]

The bug for the printer restarting the last print job was just fixed this week and will be in the next firmware release (can take a few months).

[kmanstudios 1,120]

3 hours ago, kcel said:

 

Ah, cool.  Thanks for that.

ye be welcome matey, happy to parlay......

[Marco_TvM 34]

On 2/3/2018 at 11:36 PM, Indy31 said:

The bug for the printer restarting the last print job was just fixed this week and will be in the next firmware release (can take a few months).

This may be there in the next testing release, with luck, at the end of the week.

[robinmdh 100]

On 2/3/2018 at 11:36 PM, Indy31 said:

The bug for the printer restarting the last print job was just fixed this week and will be in the next firmware release (can take a few months).

ehh, since I fixed it you should know the following:

1. There can still be another print in the queue and yes the queue uses the clean command to know when it can send the next job.
2. you can use the webUI to disable the printer (stop sending jobs to this printer) before confirming the buildplate is clean when it is not.
3. A successful print will not be reprinted if power was lost after it was finished printing but before it was confirmed that the buildplate was clean, this previously resulted in a reprint which was obviously wrong!
4. A failed print (printing during the power fail) is still kept and will be re-started... so same behavior in this case.
5. You can just manually push the bed down before confirming the print is cleaned, to do so automatically is also problematic as the bed <-> print <-> printhead adhesion may be stronger then the Z motor...
   The print may be stuck to the nozzle which is what keep it there, nothing else. So this is certainly is something the user will have to take care off and can't really be helped by SW.