Filament not sticking to the plater on left and right front corners.  

RE: Filament not sticking to the plater on left and right front corners.

From that picture it looks like you are also having some adhesion problems towards the centre back too. Is your filament dry enough do you think? I ended up buying a filament dryer in the end because I was having adhesion issues and it was only eventually fixed by drying my stock (Elegoo white PLA was the very worst offender for not sticking)

RE: Filament not sticking to the plater on left and right front corners.

You might also give the sheet a good cleaning with a paper towel soaked in dawn, and warm water. And of course, don't touch it after that.

RE: Filament not sticking to the plater on left and right front corners.

That’s a new one on me - definitely adding that to my list of ‘hacks’  nice one!

oh and for anyone in the UK, fairy liquid is the same as dawn!

Posted by: @fabnavigator

You might also give the sheet a good cleaning with a paper towel soaked in dawn, and warm water. And of course, don't touch it after that.

RE: Filament not sticking to the plater on left and right front corners.

Thanks. I doubt it is a matter of moisture. The MK4 worked perfectly until recently. The filament has not changed nor the environmental conditions. I have a Mini+ sitting next to the MK4 and have no adhesion issues with the same filament I am using with the MK4. I think it might be a heating issue with the bed. I have asked Prusa support for their thoughts on the matter but haven't received a response in several days.

RE: Filament not sticking to the plater on left and right front corners.

Thanks for the reply. But apparently you read my post very quickly or just the subject line. I said in my OP, "I have cleaned the plater thoroughly with dawn and or alcohol."  But thank you for taking the time to respond.

RE: Filament not sticking to the plater on left and right front corners.

I have also problems with filament (all sort) not stikking to plater started with 2,.8 and firmware upgrade i say that temp hotend now is 210 (was 175) by firstlayer call.

Mayby ?

RE: Filament not sticking to the plater on left and right front corners.

Thanks Wim. My bed temperature doesn't change when I raise it in Prusa slicer. I think it is either a mechanical issue (heat bed) or the firmware. I'm running firmware 6.0.3. 

RE: Filament not sticking to the plater on left and right front corners.

i agree

I just printed an "old" object that was sticking to bed (very good mayby to good) with the old bgcode (for 2.8 and 6.03) ... but now with 6.03 ... disastrous so it can hardly be anything other than firmware. Unfortunately I don't know how to restore old firmware.

RE:

from an old post in a different thread on how to revert to an old FW version:

1. Copy FW to the USB drive (make sure it is FAT32)
2. Insert the drive into the printer (turned off or running)
3. Turn on or restart the printer, upon the boot double press the knob
4. Wait for a few seconds, screen informing you about flashing the firmware will appear
5. Flash the FW.

RE: Filament not sticking to the plater on left and right front corners.

thanks,

I printed the object again,

but now with firmware 6.0.0no luck so we can write off firmware

However, the problem remains, does anyone have any ideas

other than cleaning (I have already done it many times)I also checked nozzle and many screws (nozle and z axis).

RE:

Poor adhesion is almost always due to poor bed cleanliess or, on older machines, a miscofigured first layer 'Z' offset.

Each of the solvents used to clean print-sheets has it's limitations, the trick is to use several different ones - alcohols are better at shifting grease than water but worse with sugars ... so change from time to time. 

Think about your working environment - what might be contaminating your printer and what cleans that?

We are assuming the contaminents are human fingerprints, filament residue and PEI oxidants.

But if you are using aerosols in the same room, or spraying paint, laying fibreglass, arc welding ... anything that creates dust, smoke, spray... You get the idea. The bed needs to be clean.

My routine:

Clean with IPA between prints.

At the first hint of a problem, use dishwashing detergent (Dawn/Fairy) and HOT water.

If this is not enough rub neat dishwashing detergent into the sheet, wait a few minutes then rinse clean with VERY HOT water.

If that's not enough use acetone: *On the smooth sheet only* once or twice a year at most. With satin/textured sheets only use acetone if the only alternative is scrapping the plate.

Cheerio,

RE: Filament not sticking to the plater on left and right front corners.

Hi Diem. Good points. But they don't apply in my case. The lifting always occurs in the same place (left and right front corners) and with different printing sheets (satin powder coated and steel sheet). The print sticks everywhere else so cleanliness probably isn't the problem. I'm rater disappointed that Prusa Help hasn't replied to my two inquires regarding this issue.

Hmmm ... maybe - but the front corners are the most likely sites for thumbprints...

Cheerio,

RE:

If cleaning is not the most likely culprit anymore, what about temperature? Did you print successfully when it was much colder? It that’s the case, what about directing a fan at the printer to bring down the temp?

also are you using the old bcode? With new versions of the slicer also come new profiles and usually things like temperature etc get changed… just trying to be systematic here 🙂

good luck

RE: Filament not sticking to the plater on left and right front corners.

chmax, I think temperature is exactly the issue. I have a laser heat detector and it shows 70 degrees C when the bed temp is set at 90.  And of course the left and right front corners are lower still.  My problem is how to troubleshoot the issue. If I knew what voltage the bed receives at certain temperatures I could determine if it's a motherboard issue or a bed issue. If you, or anyone else, knows of any way to troubleshoot bed temperature  issues I'd appreciate hearing them, thanks. I hate to spend money on parts without knowing what the exact issue is.

RE: Filament not sticking to the plater on left and right front corners.

That is a big difference. Did you try to reseat the cable connector that goes from CPU to plate?

RE: Filament not sticking to the plater on left and right front corners.

Alternatively try to rise the bed temp hntil your laser measures the right one and try to print…then you know what it was for sure…

RE: Filament not sticking to the plater on left and right front corners.

That's my plan. I'll also check the bottom of the heat bed to make sure the tape and grid are attached correctly.

RE: Filament not sticking to the plater on left and right front corners.

I did raise the temperature to 100 degrees in settings and still got 70 C. Thanks for the good suggestions.  I'll report back if I find the culprit.