Am I oozing too much ???

Thoughts about Raise3D, 3D printing and making in general.
Rockman
Posts: 70
Joined: Sat Jul 02, 2016 7:53 pm

Am I oozing too much ???

Postby Rockman » Tue Sep 20, 2016 12:52 am

Please refer to the images.....

Did a simple dual extrusion test.
It printed the wipe wall fine.
Cube printed well with all colors and edges seemed to align well.

Take a close look to the side of the wipe wall. It looks like the left extruder was oozing a little too much yellow filament. Black was in the right extruder.

What is causing this?
Is this normal ?
Are their settings I can adjust ?

I'm concerned on more complex prints that the yellow ooze will ruin print.

Rockman
Attachments
20160919_204529.jpg
20160919_204623.jpg

User avatar
JohnSays
Posts: 703
Joined: Tue Apr 26, 2016 2:42 pm
Location: Saint Petersburg, FL

Re: Am I oozing too much ???

Postby JohnSays » Tue Sep 20, 2016 2:04 am

That is classic under-extrusion. Give us some dertails about what material you are using, temperature, hot end, extruder, speed, flowrate... Also, check the diameter of the filament and input that into the Filament Settings... from the main menu. If you haven't done it, print a 20 x 20 x 10 calibration box. Use JetGuy's instructions: viewtopic.php?f=2&t=278&p=2620&hilit=extrusion+volume#p2620. Do this for each nozzle one at a time for the exact material and color you are going to use in it. Yes, even the color can change the print characteristics. E.G. I have some ABS+ in black that prints beautifully at 250C, but the blue ABS+ looks like junk until 260C.

I'm not sure how new you are to this. If you are new, then just get one nozzle working correctly at a time. The ooze is not your problem and is not that bad within the yellow and black print. Ooze control is done via retraction distance, retraction speed, coasting, z-hop, print speed control, temperature, and object geometry -- for example, a sudden 90 degree turn is fast deceleration, full stop, and then an acceleration all while trying to vary the amount of filament being extruded to match the speed. Not all filament is going to take well to that. Each filament type behaves differently. PLA is just plain runny unless you can "freeze it" in its tracks with a cooling fan it is going to ooze. ABS, not so much. Nylon yes. PETG is more forgiving and may be the easiest material there is to print with right now. I can hear the objections starting already... Anyway, that is my experience.

The filament even in the black squares is screen door'ish -- which also means under-extrusion. So, you could be too cold, too fast, flowrate too low, filament too thin (say 1.60 vs. 1.75). Also, the nozzle could be partially clogged with some carbonized filament from an earlier extrusion. This can happen with some filaments if the nozzle is left at full temp for too long. Especially PLA.

So a word about PLA. What makes PLA hard to work with is that it flows all at once. You don't creep up on it so that you have some flow and then a little more flow as the temperature gets hotter -- as you do with ABS. PLA hits a certain temperature and then pow! it just starts to flow right now. You can take advantage of this by getting the hot end to just the right temperature for it to flow and then quickly cooling it as it prints to freeze it right were you want it. So that is the good thing if you know these datums. The point is, that if you are using PLA and not cooling it or heating too hot, then you will have too much ooze no matter what else you do. Retraction probably will not help if it is just too hot.

Tip: When your first layer goes down it should sort of squish a bit and be flat on top vs. rounded. If not, the nozzle is too high off the bed. Beware, because too low and the nozzle backs up with filament and then either spits out when it lifts or it clogs. Balance is the answer. Your first layer should place each print pass right next to the last and flat. No visible space between runs. If you don't see that when the print first starts, then stop it, change your settings to increase extrusion rate/amount and try again.
Last edited by JohnSays on Tue Sep 20, 2016 3:56 pm, edited 1 time in total.
- John

2 Raise3D N2 Duals, Bondtech BMGs, adjustable table, Panucatt SD2224 drivers, run-out sensor, thermal overload protection, Firmware 1.1.9ABH - with Lin_Advance, Palette 2 Pro, Custom E3D hot end and ultra-light carriage and printer head

Rockman
Posts: 70
Joined: Sat Jul 02, 2016 7:53 pm

Re: Am I oozing too much ???

Postby Rockman » Tue Sep 20, 2016 2:40 am

Thanks John for the detailed reply.
Here is more info:
R3D PLA yellow filament in the left extruder(205 celsius)
Filaments.ca PLA in right extruder(215 celsius)
Stock hotend with 0.4 nozzle
0.2mm layer height

Infill, top, bottom flowrate is 100% BUT under Filaments Settings it says 94 %
Infill and top infill speed is 90 mm/s


Tried to measure diameter at a few spots with callipers seems to be around 1.76 to 1.78 for both.

I will try the Jetguy's calibration test tomorrow.

For the nozzle height, I dont have feeler gauge. Can I use a standard sheet of paper to check? I believe 1 sheet is 100microns. How many microns should nozzle be from printbed ?

User avatar
JohnSays
Posts: 703
Joined: Tue Apr 26, 2016 2:42 pm
Location: Saint Petersburg, FL

Re: Am I oozing too much ???

Postby JohnSays » Tue Sep 20, 2016 3:09 am

Your are welcome Rockman and good luck. The calibration cube is going to be your best friend. I would start by reducing your infill speed to 60. Flowrate for R3D PLA is usually 94% and every 100% is then actually the 94% flowrate -- goofy but you'll get used to it.

Simplify3D has a very good print quality document you need to know about: https://www.simplify3d.com/support/prin ... gh-plastic

Don't sweat the the height with a gauge. Just take a plain old business card and get a little drag on it. Then print some straight lines and check the squish with your eyes. If not enough, lower the head. If too much, raise it. It needs to pass the eyeball squish test not the feeler test. The feeler just gets you close. I like an easily manually adjustable table because I will raise or lower on the fly as the print starts. (And -- rant 1,298 -- that is what I do not like about "auto-leveling" tables and factory leveled tables. They may not get my first layer right -- not necessarily -- and build tables get out of true and out of level from just everyday stresses. Raise3D really needs to add manual leveling. It is a user requirement to be able to move the table z-height and level once the print is started. I can level my whole table just by printing a 12" x 12" skirt around the table and twiddling my thumb screws to get the right squish.)
- John

2 Raise3D N2 Duals, Bondtech BMGs, adjustable table, Panucatt SD2224 drivers, run-out sensor, thermal overload protection, Firmware 1.1.9ABH - with Lin_Advance, Palette 2 Pro, Custom E3D hot end and ultra-light carriage and printer head

User avatar
walshlg
Posts: 1350
Joined: Wed Mar 23, 2016 12:01 pm

Re: Am I oozing too much ???

Postby walshlg » Tue Sep 20, 2016 3:47 pm

I wonder if some of the underextrusion is because the yellow head is dripping so much plastic while its printing the black material. Its amazing that you can get it to print at all when you've lost so much material. By any chance do you have the bottom of the fan duct covered? It seems to be acting like the head is too hot. Make sure that the thermocouple and heater block are screwed in tight (yellow printing nozzle).


Return to “General”

Who is online

Users browsing this forum: No registered users and 2 guests