Cleaning hot end exterior

juliean.g

(@juliean-g)

Eminent Member

Cleaning hot end exterior

So I had that dreaded event - a failed print forming a ball of gunk around the hot end. The hot end was covered in black PETG.

I got most of it off, and it prints fine (no clog), but it just looks like crap - black all over. I picked off what I could with tweezers, but it still looks bad. Thought about cleaning it while hot with a damp cloth (maybe in IPA), but was afraid to shock cool it.

Is there a fix for this? Ideally one that doesn't require removing the hot end from the printer?

Posted : 16/06/2018 5:10 am

Martin Wolfe

(@martin-wolfe)

Reputable Member

Re: Cleaning hot end exterior

There are two ways to remove the final bits of the blob after you have finished pulling it off with tweezers :-

The Prusa recommended way is with a brass brush gently brush away the remaining bits.

Bring the hot end to the lowest printing temperature of the material that formed the blog then wipe it down with kitchen towel or an old rag being carful not to burn your fingers.

Regards,
Martin

Martin Wolfe

Posted : 16/06/2018 7:11 am

dimprov

(@dimprov)

Noble Member

Re: Cleaning hot end exterior

A nylon brush with stiff bristles also works too for cleaning off PETG after bringing the hotend to temperature. It's what I used when I faced cleaning the blob of doom. It's less abrasive than a brass brush.

Posted : 16/06/2018 5:04 pm

juliean.g

(@juliean-g)

Eminent Member

Topic starter answered:

Re: Cleaning hot end exterior

A nylon brush with stiff bristles also works too for cleaning off PETG after bringing the hotend to temperature. It's what I used when I faced cleaning the blob of doom. It's less abrasive than a brass brush.

Question: The material that globbed on was PETG, which I usually print at 241C. Nylon is printed at 240-260, I believe. Is this an issue? Will my hotend melt a nylon brush if I scrub with it?

Posted : 19/06/2018 3:48 pm

dimprov

(@dimprov)

Noble Member

Re: Cleaning hot end exterior

A nylon brush with stiff bristles also works too for cleaning off PETG after bringing the hotend to temperature. It's what I used when I faced cleaning the blob of doom. It's less abrasive than a brass brush.

Question: The material that globbed on was PETG, which I usually print at 241C. Nylon is printed at 240-260, I believe. Is this an issue? Will my hotend melt a nylon brush if I scrub with it?

Good point. All I can say is that I have not observed any problem, maybe because with a scrubbing motion the duration of contact of each bristle with the hotend is actually very short (similar to moving your finger quickly through a candle flame--nothing bad happens). So, be mindful of that and do the brushing quickly.

Posted : 19/06/2018 4:01 pm