.25 Nozzle a mess using PolyLite PLA Old Mini with new .25 nozzle

Printed one small object but now there is filament all over the nozzle. Used the following set by Cura as the profile for PolyLite PLA. Have printed this part before up to 5 at a time without any problem.

Filament is kept in a low moisture box. And it is relatively new. Used High Detail setting. Hot tip at 210 and build plate at 60. Cleaned build plate but didn’t use any glue. Also skirt with 5 lines.

Not only is there filament all over the nozzle but the filament did not adhere to the build plate like it should.

So what about temperatures? Do I need glue on build plate? Why poor adhesion? How do I clean the nozzle? Also this is a very small part about 30 x 30 x 15 mm.

Thanks, Jay Beckham

How was your first layer squish? When changing heads you may need to re-adjust your Z offset to ensure the first layer is pressing down enough for good adhesion but not so much that it is digging into each layer. If it is too low then the head might catch bits of the previous layers oversquish. Might be a good place to start.


Set the flow for the first layer to 102% to 103%. That is Custom > Material > Flow > Initial Layer Flow Rate 102% is what I have.

The micro nozzles like that are always messy. They are covered in ooze and pick up the filament hairs and just turn gross. Heat and wipe clean with the 3M red pads between each use.

Using the flow rate turned up slightly should make plate stick better though.

PS. Don’t adjust your Z-Height unless the flow rate adjustment doesn’t work. If you are printing for accuracy you get other problems. Increase the flow rate instead.

Most likely a Z-height adjustment.
Or, is filament oozing from top of block? (Is top of nozzle (internally) seated tightly with bottom of the heartbreak?)
I print PolylitePLA frequently, 100% flow, use 1000 grit on build plate weekly and wipe down the plate with alcohol/water mixture before each print.
Oh, and printer setup is for .25 nozzle?

Thanks for the advice. I set it at 103% and cleaned the bed again using 1000 grit and alcohol and got a good print.


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What exactly is 3M red pads?


All I can find is 18 inch diameter pads for polishing floors.


3M is the company, Scotch-Brite is the brand name. You can search for Scotch-Brite and find lots of information / sources. I believe “red” is actually “maroon”.

SCOTCHBRITE GRIT CHART (courtesy of Charlest)
3M Scotch Brite Nylon Pads:
7445 - White pad, called Light Duty Cleansing - (1000) 1200-1500 grit
7448 - Light Grey, called Ultra Fine Hand - (600-800) 800 grit.
6448 - Green (?), called Light Duty Hand Pad - (600) 600 grit
7447 - Maroon pad, called General Purpose Hand - (320-400) 320 grit
6444 - Brown pad, called Extra Duty Hand - (280-320) 240 grit
7446 - Dark Grey pad, called Blending Pad (180-220) 150 grit
7440 - Tan pad, called Heavy Duty Hand Pad - (120-150) 60(?)
Green Scotch Brite is available EVERYWHERE. It's 600 grit.
Blue Scotch-Brite is considered to be about 1000 grit.
(The value inside the parentheses is directly from 3M.)
3M Chart
Less Aggressive --------> More Aggressive
7445 7448 6448 7447 6444 7446 7440
Finer Finish --------> Coarser Finish

Thanks. I did find Maroon but wanted to be sure. Thanks for the quick reply.