Printing natural pla and wall adhesion.

[BrickHaus]

Alright. I need tome tips from the pros. My root question is: What are your tips for printing natural filaments?


As some of you know I've been printing drill index blocks for my co workers and myself. Well, I've been attempting to at least.

I got both printers set up to print out of my dryer. The natural pla on the right printer is fairly old. ( bought it last year when I got my first printer)

The pla on the left is a fresh spool.

The printer on the right has printed nice drill blocks on my old roll of black filament. Same program with this dried natural pla shows wall separation ONLY on the 3 vertical walls. Each vertical layer is strongly bonded, but the horizontal walls are all un attached. Its done it on 3 blocks with slight programming differences.

after my first one showed this, I looked at my sliced program, qnd I had my fan speeds at 100%. With the dual fans this is over kill, so I figured I over cooled the walls.
So I re ran it with 40% fan speed like I typically do on this printer.


The one I pulled this morning showed this issue as well.


I looked through my parameters this morning, and I changed the " outer wall offset" by a value of 0.2mm which is said to help adhesion.

I also changed the outer wall flow to 103% figuring it would help.

I just got home to this... same exact thing, and it seems to be this filament specific.

I recall being told by my old co workers that natural filaments are harder to print. I alwqys thought it was because they stayed goopy too long without cooling..

Do you guys do qnything special to print clear filament?

I can give a list of my print settings, but I figured the base question for natural filament may not require it.

[goofyman23]

I dont have any specific knowledge on natural filaments, but what is your wall overlap set to? Do you get delamination elsewhere or issues with layer separation? I might also try a temp tower and then a fan tower to see where that specific filament might be happier.

[BrickHaus]

Ill check wall overlap. Thats a stock value in cura I'm sure. I try to not mess with variables until stuff doesn't work, but I assume I need to change something here. Ill look into it.. whats a good rule of thumb? Im running the typical .4mm nozzle for reference.

For this print the skin has a few flaws sporadically, but the inner walls are tough. The infill (lines) is plenty strong and adhered to everything around it. Its simply the 5 outer walls are all by themselves.

The 45* face has some flaws in it, but its solid.

[goofyman23]

For functional parts, I usually use a line width of .48 and a layer height between .2-.24.

Yes, Cura has a wall overlap setting, think default is 30%. Can also try a different infill pattern.

[XEMON]

I'd check line with too ...
what's your speed and temp?
do you print infill or walls first?

PS: you can cut your infill density down, gonna save you some filament.

[BrickHaus]

All my line widths are .4.

Been at 212 at the nozzle, 60 bed. going to scrap current print.

The sequence is outer walls, inner walls, infill, hop.

and thanks on the infill. I had it at 5%, but cura seems to default back to 10% after a reboot or something. I have 2 active versions of cura so it gets all messed up.. this was a 2 AM start a print and go print.

I feel I have have to do lines to increase my odds of having infill under the base of all of the drill spots. But 5% seems to work.

I went through like every infill messing around trying to hit every drill or tap holder as it climbs. Being they all start in space. Eventually I got sick of it and just did lines and made more of them.

[XEMON]

well ... doing lines always help 😅

212 seams a bit low, but i tend to print hot ... less details, but better adhesion.
Whats your print speed?

If you are worried about it, make a tiny hole from the bottom of the part to the bottom of the holes, teh slicer will think its "outside wall" ... abasically tricking the slicer to make internal support where we want.

[BrickHaus]

Thats where I think natural filament gets tricky. I always thought hotter prints will make clearer lines, and let more light through. With natural filament it seems to retain heat longer or it at least likes to stay soft longer so it gets goopy and stringy.

Run it cooler and the lines look nice and clean, but adhesion is tough.

Again this is just my theories. Ive wanted to make clear parts since day one, but natural filament is proving to be hard to use.

This really stems from my rocket molds. I wanted to initially make clear enough molds that I could hold them up to light, and see how the foam was expanding. Ive never been able to print clear well enough to do just that.

[Rainmaker]

I'm not sure if this would help, but have you tried rotating the part on the print bed a little? Like 5 degrees or more? I founds sometimes that forcing the printer to use both X and Y steppers (diagonal line) can do something different than when just printing aligned parallel to your axes. I don't know, might do nothing. Also it wouldn't help you "understand" the problem.

My only other thought was to ask if you have calibrated your e-steps?

[Rainmaker]

Edited: Meant to say it WOULDN'T help you understand the problem

[BrickHaus]

Honestly. The E steps is a huge factor. I figured that out last night, and Im running one now to see what it looks like tonight. My ender 3 v2 seems to pitch the settings after a while. With my current extruder I need to set the e steps to 137.3. I have that memorized because it defaults back to 93 after the printer sits for a long time.

Well, I got these going the other way, and I haven't shut them down, but the e steps were 93.. i set them to 137.3, stored the settings, went to the main menu, cycled power, and it was still 137.3. Yet after my next print it defaulted back to 93.

Im fairly certain I need a firmware update on this printer, but I'm afraid of bricking it trying.

With my set up, I need

[BrickHaus]

I changed a bunch of variables, wall line width from .4 to .2, temperature from 220 to 225 ( max on the roll), and turned on " connect infill lines" which seems to help eliminate a ton of recreations.

What I really wanted to share and chuckle about is the fact the the infill is global on the slicer, so I rotated my part and now the infill is 90* out from the walls rather than 45* Once again I threw a program together before work and headed out to work, so this was a surprise.

Looks good enough