Burning & Blobbing  

RE: Burning & Blobbing

As it stands right now, I think my issue(s) were....

1) The nozzle got clogged once... I ran a cold pull to clean out the nozzle

2) That clog likely did not get completely cleared which lead to more "junk" and poor extrusion of the filament

3) This caused blobs and excessive deposits due to excessive pressure build-up behind the extruder nozzle

4) These blobs created build-up within the model, just like you described... half way up the build to start with and then the problem started creeping closer and closer to the build plate until eventually, I could not get the 1st layer to print clean.

5) This build-up would catch the nozzle, stick to it and gum up material all around the heatsink block which lead to more clogs and more build-up

6) Wash, rinse, repeat... this just kept getting worse and worse with every failed build

My solution was multiple things being done....

A) Replaced the nozzle with a PRUSA factory purchased nozzle (gonna buy a dozen more to keep on hand for the future)

B) A thorough cleaning with a brass wire brush of the heat sink and surrounding components

C) A thorough purge of the system... literally used around 1/2 cubic inch of material to purge out

D) Bought a triple pack of silicon socks for the E3D print head... money well spent to prevent blobbing build-ups from sticking to the heat block and nozzle.

E) Even though the beds were all thoroughly washed with Dawn in super hot, soaking water... then thoroughly cleaned with Acetone (the strong stuff... not watered down nail polish)... I tried a print and adhesion issues still remained so I used the glue stick.  Problem solved

While the glue stick, in my opinion is not the actual answer to correct the root problem... it is a viable "work around" to the adhesion issue.  It gets me printing again to make my deadlines to my customers... making me money once again.  Eventually I will get around to further digging in to find out why I need the glue at all but for now.... the glue makes the parts stick and I'm getting 5-6 prints from the bed before I have to thoroughly clean the glue off.  Piece of advice... go to Lowes/Home Depot/etc... get a 3-pack of *plastic* putty scrappers or paint scrappers.  They won't scratch up the bed but they do an excellent job of cleaning that glue residue off.  If they dull.... break out a palm or belt sander and give them a good honed edge again.

I hope this helps others that have/are having similar issues.

RE: Burning & Blobbing

@scott-a-mayo

Hi scott, from amazon I have had success so far with GIANTARM filament, I have only used two rolls but its been perfect, I found the temp best at 210oC.

Nicely wound as well.

RE: Burning & Blobbing

I’ve used Overture, Hatchbox, 3D Solutech, eSun PETG, all worked great. And of course Prusament, which is great (and the way it’s wound is a beauty to behold) but shipping to the US adds to the cost.

Actually I just got a spool of gray Prusament PETG, and it’s giving me some layer adhesion issues. I guess I’ve got to run a temp tower for it. 

RE: Burning & Blobbing

I have had success with several rolls of SunLu PETG filament on my 2020 MK3S kit build.  I clean my textured plate with a few drops of Dawn every two weeks and have not used alcohol for over two months.  I had problems similar to the original post and solved that by moving to a smaller Live Z of -1.345.  Just a few hundredths (x.xx) change in the Z cause mine to go from pictured blobs to a smooth.  Don't give up as there is a setting where everything will work 😊 .  I switch from PLA to PETG regularly with few or no problems.  I wash the sheet, scrubbing lightly with a wet paper towel and dry with a paper towel; then put the plate on the machine and set the Preheat to PETG to finish the drying process.

I originally worried the cheap (US $16) SunLu might be poor quality but found it lay down as smoothly as Pursament.

RE: Burning & Blobbing

I want to thank people for chiming in. By washing the bed in dish soap and changing the model to have more square inches of footing, I got through the PETG print. I then switched back to PLA for what should have been a slam-dunk simple print - basically a box, open at the top - and the bottom layer curled upwards at one corner and ruined the print. I broke out the glue stick for the first time ever and got through the print job, but I'm pretty sure there's just something no longer quite right with the printer. It passes tests, and the only issue is that I haven't been able to get the X belt tension up to 240 (it's 238) and I don't think that's the problem. Prints that succeed generally come out neatly, so I think the problem is strictly in Z or temperature. (The surface of the bed is reliably 3 degrees C colder than the printer thinks it is, maybe a factor.)

I'll check out the suggested filaments. What's the shelf life of a spool once it's opened up? I had black PLA filament snap when the printer tried to pull some in; I reloaded it and it worked ok,  if a little blobby after that. It's been out in open air for 3 months. Is that an issue?

When I have more time I'll do extensive tests with the Z setting

RE: Burning & Blobbing

@fuchsr

I keep trying SunLu as if my hopes will make it better filament than it is.  I've returned 3 different color spools of SunLu filament because of a complete deviation from filament size.    One spool was completely at 1.05mm diameter in the middle of the spool..  The gears wouldn't even grab it to move it forward at that diameter..  I was trying to figure out why my print just stopped extruding...   Ridiculously bad quality control.

My current less expensive filaments are solutech, overture, hatchbox.   Wish Prusament wasn't so insanely priced in the USA.

RE: Burning & Blobbing

@christopher72

Ah, I just can't keep myself from re-ordering Galaxy Silver PLA from Prusa, despite the shipping. 

"We wants it, we needs it. Must have the precious".

RE: Burning & Blobbing

I have to agree - Prusament glaxaxy silver pla and FilamentOne Silver Glint are my two favorites.  

RE: Burning & Blobbing

@kendred

You shouldn't need a dozen spare nozzles mate.

Get your nozzles from E3D directly. It's cheaper and is where Prusa get them from anyway.

I also recommend getting the 'plated copper' nozzles instead of the standard brass ones. They are nickel plated, which makes them virtually non-stick. This makes them easy to clean and less prone to jamming/clogging.

RE: Burning & Blobbing

@morphias

AWESOME info bud... I had no idea about the plated nozzles.  I will order a couple of those instead.  Thanks again!

RE: Burning & Blobbing

@morphias

What size nozzle comes standard with the MK3S? My eyes can't make out any markings, and I want to replace with the same size I have now. Is it 1.75/0.3mm?

RE: Burning & Blobbing

@scott-a-mayo

0.4mm is the standard size

I also highly recommend 0.25 is you are going to be doing prints with fine details and/or small text.

I swap between 0.25 and 0.4 up to 6 times a day. Getting to the point where I need a printer dedicated to each size.

RE: Burning & Blobbing

Can I assume these multipacks of nozzles from amazon are going to be hot garbage?  The ones I purchased were like 6 quid for 10. I have not used them because the nozzle end is longer meaning adjusting the pinda and stuff so they have remained there. But looking at E3D a single one is 9 quid.

RE: Burning & Blobbing

@garethsnaim

I think you've answered your own question. 🙂  They are not correct for your printer.

Yes, the genuine ones from E3D are more expensive, but they last a very long time - especially the plated copper ones as long as you're not using abrasive filaments like CF/Steel/Glow.

There is an old saying: "Buy cheap, buy twice".

Things that are dirt cheap are dirt cheap for a reason. You'll likely find those cheap nozzles will clog and not extrude properly. There will likely be tiny 'dags' and swarf in the castings and the aperture is unlikely to be accurate/in spec. I mean, we're talking about tenths and hundredths of a millimetre. The chances of them having being cast with any sort of accuracy are very remote.

I do a lot of printing for my business and am yet to wear out a plated copper nozzle after 9 months of heavy, daily usage.

RE: Burning & Blobbing

At 46 years old I am well aware of the value of things! Which varient do I need on E3d, V6?

RE: Burning & Blobbing

Posted by: @garethsnaim

At 46 years old I am well aware of the value of things! Which varient do I need on E3d, V6?

Yep. E3D V6 hotend is what the MK2 to MK3S+ run. They fit the Mini as well.