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help with lost adhesion please?  

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jpadie
(@jpadie)
Eminent Member
help with lost adhesion please?

I've had an Ender 3 for about a year.  I recently came to the realisation that I was spending so much time nursing it that I had become a 3d printing hobbyist, rather than an electronics hobbyist that needed a 3d printer to help with a few small aspects. 

So I junked the printer.  In the year that I had had it, I got 6 prints that were any good.  And spent more than 20 man days trying to get good prints.  

So I decided to spend 4x the money and buy a i3mk3 in the hopes that this would 'just work'.   and after three days of building the printer slowly, I was pleasantly surprised that the first week of prints were all more or less perfect.  

yesterday I printed a pogo pin clamp for a sonoff, in PLA and it was perfect.  I went out whilst it was printing, came back a couple of hours later, removed it from the bed, cleaned the bed as usual (90%+ IPA) and turned off the machine.

today I have spent four hours trying to get a single print to work.  I'd lost all adhesion.  So I cleaned the base (smooth) with acetone and tried again.  No improvement.  I recalibrated, no improvement.  I brought the PINDA probe a notch closer to the bed; no improvement.  I redid the wizard self tests and that was fine. 

In more than 30 calibration prints, I have not got one that is even vaguely right.  at most I get half a line and that's rarely adhered - at very high z-offsets I get all the lines but no precision on the corners and no adhesion - the filament is just draped on to the board).  In the near right hand side of the bed, the filament seems to start bundling into the hotend and then by the time it gets to the wee rectangle it's just a plastic bung.

Before I give up and junk this machine are there any known fixes that I can try?  

Just to reiterate:

1. zero changes between yesterday and today except ambient temperature perhaps 1.5-2C warmer.  
2. i reiterate: zero changes.  none at all.  

3. today I have tried with the known good PLA and when that failed on all of 25 prints, I changed to a new roll of PLA; no improvement. 

 

thanks in advance.

Justin 

 

Postato : 13/03/2020 2:12 pm
bobstro
(@bobstro)
Illustrious Member
RE: help with lost adhesion please?

This one's a leap of faith, but trust me: Take it to the kitchen sink and give it a dunk under the kitchen sink. Give it a scrub with plain dish soap (Dawn in the US, Fairy in UK). Use a clean plain paper towel (unscented etc.) to scrub it and another to dry it. Avoid touching the print are. Do not wipe it with alcohol or any other preparation. Immediately do a Live-Z adjustment, Jeff Jordan's "Life Adjust" is recommended

The PEI print surface is amazing stuff, but it must be kept clean. Alcohol & acetone break down surface grease but do not wash it away, so it can accumulate. The dunk washes the crud away with many times the volume of liquid, so is amazingly effective. If I had a sink nearby, I wouldn't use any other cleaning technique on PEI.

These alien technologies can be baffling. I've got more notes here you may find interesting. Good luck with it!

My notes and disclaimers on 3D printing

and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan

Postato : 13/03/2020 2:30 pm
jpadie
(@jpadie)
Eminent Member
Topic starter answered:
RE: help with lost adhesion please?

@bobstro

happy to try washing with a surfactant but I'm nowhere near Jeff's print calibration square.  at the moment I literally have zero adhesion.  just filament wafting across the print bed until it bundles up.  

Postato : 13/03/2020 2:41 pm
DJ
 DJ
(@dj-6)
Trusted Member
RE: help with lost adhesion please?

@justin-adie

You mentioned that you tried recalibration. I just want to explicitly ask if that included the Calibrate Z selection from the menu.  I always have to do this after a power cycle because my z axis is adversely affected by gravity when the z motors turn off and this affects my z height. 

DJ

Postato : 13/03/2020 2:52 pm
jpadie
(@jpadie)
Eminent Member
Topic starter answered:
RE: help with lost adhesion please?

Hi

Yes I did the start up wizard again and this recalibrates all axes. 

Postato : 13/03/2020 3:00 pm
bobstro
(@bobstro)
Illustrious Member
RE: help with lost adhesion please?
Posted by: @justin-adie

[...] happy to try washing with a surfactant but I'm nowhere near Jeff's print calibration square.  at the moment I literally have zero adhesion.  just filament wafting across the print bed until it bundles up.  

Which sheet are you using? Smooth or textured? The Dawn Dunk should work with either but it would be helpful to know.

Do the wash and let us know where things stand. Is it possible the printer was bumped or moved overnight? That could throw Live-Z out of adjustment. If Live-Z is too high (less negative) you will get very much the pattern you've described as there's nothing to press the filament onto the PEI. In any case, a clean print surface is an essential 1st step and both PEI cleanliness and proper Live-Z calibration are essential.

Based on your description, I'd do the wash the PEI then zero Live-Z and work downwards (more negative). Specific numbers depend on your printer, but for a smooth sheet, expect to go down -0.500 or more. Just work slowly and let the printer respond before making dramatic adjustments.

Once you've done both correctly, you should have no issues with adhesion:

Please update with your status. This is a common experience, so don't get too stressed out about it.

My notes and disclaimers on 3D printing

and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan

Postato : 13/03/2020 3:18 pm
jpadie
(@jpadie)
Eminent Member
Topic starter answered:
RE: help with lost adhesion please?

@bobstro

thanks for the help.  I followed your advice and scrubbed the base with fairy liquid (although I am based in France, I happen to have some of the real thing from the UK).  I then redid the z-calibration and another 15 or so calibration prints.  I eventually started getting adhesion at about -1.1mm.  Although to my eyes the filament looks much too squished.

the first 'real' print I tried adhered adequately but the detail was no good.  I suspect this is a design issue as some of the internal structure requires 0.4mm walls.  

i then tried the live-z test you suggested and got pretty questionable results.  I am curious as to whether received wisdom is that this shows the z height as too close to the bed (too negative) or the inverse or something else altogether!  

pic of the print is here:
life-z

Postato : 13/03/2020 8:51 pm
rmm200
(@rmm200)
Noble Member
RE: help with lost adhesion please?

Picture failed to come through...

If you can't see it after you post - we probably can't either.

Forum is really picky about what works.

Postato : 13/03/2020 10:37 pm
Nigel
(@nigel)
Honorable Member
RE: help with lost adhesion please?

Use Glu stic it always works for me. The PEI and textured sheets do not work, despite many attempts by me. The first layer is always corrupted.  I now use UHU glu stick on my textured  and PEI steel plate sheets. Problems for first layer gone away. I have tried many times with first layer calibration. But always some part of the bed fails and corrupt first layer. When I print large objects.

Questo post è stato modificato 5 years fa da Nigel

Nigel
Life is keeping interested and excited by knowledge and new things.

Postato : 14/03/2020 4:14 am
Nigel
(@nigel)
Honorable Member
RE: help with lost adhesion please?

First layer calibration I tune to be perfect. But final print always has issues with adhesion and gaps. I did clean with 99% IPA and recommended window cleaner. Glu stic always sorts this out when applied to the print bed. PEI and Textured. Textured  is much worse.

Questo post è stato modificato 5 years fa 2 tempo da Nigel

Nigel
Life is keeping interested and excited by knowledge and new things.

Postato : 14/03/2020 4:23 am
jpadie
(@jpadie)
Eminent Member
Topic starter answered:
RE: help with lost adhesion please?

@robert-rmm200

That's odd as I could see it in the preview and in the thread after I posted. And can see it now!  

 

Here is an external link

 

https://photos.app.goo.gl/swYWesxSW7F134jC6

Postato : 14/03/2020 10:03 am
jpadie
(@jpadie)
Eminent Member
Topic starter answered:
RE: help with lost adhesion please?

@nigel

I used glustick on the ender 3 with no result. Both on the flexible surface and on a glass bed I bought.  

I am reticent to try it on the MK3 as the spring steel sheets are crazily priced and I've read all over the place that glue can actually prevent adhesion. 

 

My take on this is that I would really like to understand why the prints suddenly failed overnight with zero intervening change.  The z gantry recalibrates on z-home, the pinda probe doesn't move independently of the extruder and there is no possibility of jogging as the printer is in a closed off room.  

 

In any event hopefully the reposted photo link will shed some light on the current issues and your collective wisdom will guide me!

 

Thank you!

Postato : 14/03/2020 10:08 am
JoanTabb
(@joantabb)
Veteran Member Moderator
RE: help with lost adhesion please?

@justin-adie

Hi Justin, 
I am on e of the moderators on here. 
I added your picture to your post, above.  this will preserve the link for future readers. 

Are you using 7x7 mesh bed levelling?   the printer is normally sett o the default 3x3 mesh bed levelling, 
change using the LCD controls on the printer!

regards Joan

I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK

Postato : 14/03/2020 11:51 am
jpadie
(@jpadie)
Eminent Member
Topic starter answered:
RE: help with lost adhesion please?

@joantabb

Thanks for that .

I changed to 7*7 but I see no improvement.  In fact since then I get no adhesion at all. 

 

I fear that's as much time as I can afford to spend on this. 

 

Thanks anyway. 

Postato : 14/03/2020 2:45 pm
Nigel
(@nigel)
Honorable Member
RE: help with lost adhesion please?

@justin-adie

Its easily washed off as water soluble. These Glu Stics I bought from E3D in a sale. Back in the day. They no longer sell them?

Its my solution, it maybe not for others. However my large PETG print, came off the bed easily after print ended, with zero artifacs on first layer. This print covered the majority of the textured print surface. A large bracket.

Nigel
Life is keeping interested and excited by knowledge and new things.

Postato : 15/03/2020 3:32 am
Nigel
(@nigel)
Honorable Member
RE: help with lost adhesion please?

@justin-adie

Precisely my problem with larger prints. I use 3 x 3 levelling. Try this print with added glu stick across area of print. It can be easily washed off after.

@Joan I will try 7 * 7 mesh levelling.

Nigel
Life is keeping interested and excited by knowledge and new things.

Postato : 15/03/2020 3:40 am
Peter M
(@peter-m)
Noble Member
RE: help with lost adhesion please?

Keep steel plate clean is important.

Wash with dish soap, a few times 2 or 3 times.

Z layer adjustment is very important, ( i had the problem also, it was not low enough). Try to go lower.

All axis calibration is not needed, except if you move the printer, z calibration you can do, check if it hits the top, at the same time.

Extra settings to try, slow first layer to 10mm or 15 mm.

1 layer, make the extruder hotter, 5 degrees.

With every print check the first layer, and adjust it on the fly, this is very important.

Postato : 15/03/2020 5:13 pm
Peter M
(@peter-m)
Noble Member
RE: help with lost adhesion please?

3dprinting will never be easy, you have to learn.

And it will never be like start and it works, and model is ready, there will always be problems.

Your creality will work if you learn it.

Postato : 15/03/2020 5:16 pm
Peter M
(@peter-m)
Noble Member
RE: help with lost adhesion please?

On the forum is a movie for first layer, with a good zoom on the layers. Search for this.

Questo post è stato modificato 5 years fa da Peter M
Postato : 15/03/2020 5:25 pm
jpadie
(@jpadie)
Eminent Member
Topic starter answered:
RE: help with lost adhesion please?

I am grateful for all the advice.  genuinely.

My real question is 'what could have changed' to make a perfectly functional printer into something entirely useless?  Given the precepts that nothing physical or electrical interacted with the machine from the moment of the final successful print and the next morning.  The _only_ change being an increase in ambient temperature by 1.5C.  

Since that moment I have only had one test print that has stuck and that was awful.  In _every_ other case either the filament just wafts across the bed or it balls up around the nozzle (which is not blocked).  

applying glue may be a sticking plaster type solution but the bed surface should not fail adhesion after only 20 hours of printing.  and by the by the underside of the bed (never used before) exhibits identical symptoms.  

This is not a simple z-height issue.  I've tried re-calibrating and now more than 100 first layer prints at changing 0.1mm heights. nothing works at all. 

It's as if, somehow, the entire extruder construction has cr*pped out.  

do I disassemble and rebuilt the entire assembly or is that a pointless exercise?  In which case I'm guessing the answer is that this will never be the workhorse/minimal intervention printer that reviews claim it to be and I should abandon the milieu until it matures further.  

I'm open to anything sensible that doesn't involve glue - but really I want an answer to the _cause_ of 'what's changed' rather than a patch to the symptoms

Postato : 15/03/2020 7:32 pm
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