Nozzle scrub brush is damaging my nozzle tip

[Penatr8tor]

40 minutes ago, geekandi said:

These are exactly what I use and I have destroyed 3 CHT nozzles with them in 2.4s and Trident.

I have changed my start now. I still hit the brush but for far less swipes (about 1/10th - 3 swipes) and my nozzles thank me, and my wallet.

Ditto. Same Amazon brushes and I also reduced the number of swipes to three. My nozzle is set so that the tip is only a couple mm deep into the brush.

Here's a pic of mine that I took a few days ago when I upgraded to TAP and cleaned up my hotend. It's a Rapido with Diamondback .4mm nozzle. This hotend and nozzle has printed well over 500 hours & 3000 meters of filament. If you look closely, there's a few small grooves where the tip is mounted. For the most part it's fine tho.

Edited February 8, 2023 by Penatr8tor

[geekandi]

44 minutes ago, Penatr8tor said:

Ditto. Same Amazon brushes and I also reduced the number of swipes to three. My nozzle is set so that the tip is only a couple mm deep into the brush.

I got some 1200 hours out of my original CHT on my Trident with scrubber in place.

Then, back to back to back, had printing issues on 3 machines and every one of them had a horrible amount of damage on the nozzle.

Brushes were installed at different times over different orders so it is not a specific batch.

I'm almost to a point where I am going to forgo the scrubbing. I have done some 100+ prints over the last few months where I was *at* the printer and had no ooze or strings hanging around. I also changed things after the initial CHT issues where I retract some 15mm of filament prior to park and cooldown then upon start I push forward 7-8mm then let the purge line continue to actually prime.

[Penatr8tor]

17 minutes ago, geekandi said:

I'm almost to a point where I am going to forgo the scrubbing. 

Yup, Any decent hotend these days will heat up in under a minute and the thermal expansion between 150 and 270 isn't enough to affect precision so just do all your probing at 150 and heat up and purge right before printing. Getting the order of operations correct is the difference between success and frustration.

[Buurman]

For the next one, I ordered brushes in 10 places I think, to test them... and yes, some were steel.. assholes..  

Also received some that barely have some wires in them.. 

These are great, tested them with magnet and are brass or copper... and still cheap, right size, and good thickness of wires.

https://nl.aliexpress.com/item/1005004110875937.html?spm=a2g0o.order_list.order_list_main.46.21ef79d2Lja6Vv

 

[geekandi]

quick reply:

I have updated things further and now have a few hundred hours without any nozzle scrubbing at all.

1. end of PRINT_END - retract 15mm
2. end of PRINT_START, just before purge - extrude 7-8mm (still testing)
3. all pre-printing temps at 150C during homing (Tap), QGL/ZTA, meshing, re-homing

Haven't had any issues across multiple printers.

[Agilato]

On 2/17/2023 at 9:52 AM, geekandi said:

quick reply:

I have updated things further and now have a few hundred hours without any nozzle scrubbing at all.

1. end of PRINT_END - retract 15mm
2. end of PRINT_START, just before purge - extrude 7-8mm (still testing)
3. all pre-printing temps at 150C during homing (Tap), QGL/ZTA, meshing, re-homing

Haven't had any issues across multiple printers.

And you don't have any clogs? I had couple of nasty clogs with my Stealthburner on Dragon Hotend and Bontech CHT nozzle, when END_PRINT macro had 6mm retraction distance, after changing to 3mm no clogs but leaking.

[YaaJ]

On 2/8/2023 at 11:06 AM, Rixi said:

Has anyone ever considered or tried to use a simple toothbrush for this?

I've been using cheap ones for 3 or 4 years. Banned the metallic brushes.

And always brush by hand. But had fun making a crappy scrubber and some macros in Marlin, until I was tired with replacing the nozzles.

Edited December 1, 2023 by YaaJ

[WINEDS]

Although I've tried them I never like the idea of using an abrasive brush to scrub nozzles.  Coming from an electronics background we always use a wet sponge to to clean the soldering iron tip.  So this is my goto for nozzle cleaning now.  Buy some kitchen cleaning sponges from the Supermarket and cut them into smaller rectangles then moisten them with a spray bottle.  Works a treat and is part of my 3D printing workflow now.

Edited December 6, 2023 by WINEDS