Prusa One: Nozzle Cleaning Error  

RE: Prusa One: Nozzle Cleaning Error

Anyone, when cleaning the nozzle with ABS filament installed and configured, shouldn't the nozzle temperature be greater than 170C, what do others see ?

RE: Prusa One: Nozzle Cleaning Error

I have the same Problem with PETG, even if the Process is done properly.

Sometimes i need up to 5 attemps to get it started.

RE: Prusa One: Nozzle Cleaning Error

I have also the same problem with PLA Silk. I need up to 3 attempts to get it started. Please  Prusa Equipment, do you have this same problem?

ABS, PETG and PLA all absorb moisture from the surroundings if left open; PETG is affected worst of the three but all are affected and one symptom is that the water boiling off in the hot end messes with the internal pressures causing oozing which, of course, interferes with the levelling procedure.

For this reason those in the habit of loading the printer, leaving it loaded and starting a print later are making a rookie mistake. [Unless, possibly, they are running from active dryboxes] as the degredation starts as soon as the filament is exposed to the air.

The only sensible way to operate is to load freshly dried filament and start the print job immediately, that way, although the outer layers of the spool are absorbing moisture you are likely to be using it before it has time to deteriorate and the layers newly exposed are also used before they are spoiled.

At the end of the print unload the remaining, now damp, filament and load fresh for the next print so generally you will be printing with one set of filaments whilst the others are being dried.

As you have to be present to unload remove the print and load new filament you never need to worry about remote starting problems - unless you are running a farm in which case your employees will be handling the machines and you need only concern yourself with the queue.

'Silk' filaments are designed to foam as they are heated so they always mess with the internal pressures and ooze - they will cause levelling problems even if properly dry.  If you *must* use silk the best trick is to start a first layer of regular dry filament and switch to the silk for the second layer onwards, otherwise you will have to babysit the start of the print and wipe the ooze away as it forms.  If you are using silk just for cosmetic affect be aware that you can often get as good if not a better finish with filler, sanding and spray painting.

So, dry your filaments and keep them dry, many profiles will probe at a lower temperature to reduce oozing but boiling water will always win.

Cheerio,

RE: Prusa One: Nozzle Cleaning Error

I don't think my issue is really anything to do with moisture though. The filaments are new (< 1 month old), it is working in a low humidity house room, < 44% (its been dry/warm the past 4 or more weeks in the UK). Over the last 10 years with other 3D printers in use here, moisture has not been an issue with the ABS I have used (most previous prints were in ABS and some filaments were over 4 years old). Even if the print quantity was affected, at least the printers printed something.

Does anyone know what this nozzle cleaning process actually is and how the printer determines it has failed ?

I would assume the printer oozes out a touch of filament and then moves the head close to the print surface to scrape off a bit of filament, and if it sees no filament has moved through the head (some means ?) it indicates failure ?

Is 170C with ABS hot enough to actually ooze out the filament for this if so, is this temperature adjustable ?

Is there any way to disable this nozzle cleaning process ?

I don't think my issue is really anything to do with moisture though. The filaments are new (< 1 month old),

This ought to be a sticky.   New does not equal dry.  It was packed dry but you have no idea how long it sat on a wholesaler's shelf or how it was treated in transit.

it is working in a low humidity house room, < 44% (its been dry/warm the past 4 or more weeks in the UK).

I usually try to get filament below 15% humidity, I don't always succeed.  I too am in the UK; dry, meaning no rain, does not mean a dry atmosphere.  Spring and autumn are always the worst seasons worldwide but add summer in the UK.  When no heating or aircon are needed the indoor ambient air is at its most humid; right now a print started with freshly dried PETG is showing stringing from about 6 hours in, not enough for problems completing but if the spool were left on for another print I would expect oozing, zits and cleaning issues so it will go into the drier whilst a freshly dried spool will be loaded in its place.

If the nozzle oozes during preheating the filament is damp.   'Zits' from the levelling probe mean the filament is damp.

The 'cleaning' process dabs to break off any old ooze and then taps the build sheet looking for a crisp response.  If a pad of fresh ooze remains the response is soft and cleaning has failed.

Cheerio,

RE: Prusa One: Nozzle Cleaning Error

My filament have ten days...

RE: Prusa One: Nozzle Cleaning Error

There is an issue with the nozzle cleaning process and its a known issue. Support knows about it and in my conversations with Prusa they are hoping 6.3.3 FW will solve it. 

This has nothing to do with wet filament. 

RE: Prusa One: Nozzle Cleaning Error

Thanks a lot Print_Fandango. I’ll wait for the next fw update

RE: Prusa One: Nozzle Cleaning Error

I would make sure to follow up with support in case you decide to return the printer. 

I sent mine back for this and another issue, bed level. I didn't want another hobby fixing a printer. So I will send it back as many times as required unless they offer me a 100% refund including my shipping costs