mortal shard
I’ve been struggling with under extrusion on my rookmk1 are quite a bit now and it usually happens after a travel movement or retraction, but it can just happen without that either. I’m trying to figure out why. I’m using a triangle labs extruder and hot end so that shouldn’t be the problem and I am printing at 220 Celsius. It’s probably slicer settings if anyone could help that would be great thanks!
pure ice
Heh, if not about imprecise movement, and you have retraction tuned properly. Try to use a bit of detraction. Have to use it on one of my machine to add just a little plastic to start on a new line
mortal shard
Does it seem to be much under extrusion, if anything it looks over, extruded in some places, but than others like thinner, circular parts, it under extrudes a bit I can share my or slicer profile if that might help
mortal shard
Yes, I do have callipers and it’s just PLA but it’s probably a bit moist that could be a bit of the under extrusion problem but it did the same thing with a brand new spool maybe I just don’t have my retraction set properly but on the benchy I printed there weren’t much strings at all.
This is my first 3-D printer I’ve built so I’m kind of new to changing a bunch of settings
opal kiln
measure the inner wall thickness , if the filament is wet im expecting it to be 0.42 ish
mortal shard
dull hatch
Does it seem to be much under extrusion, if anything it looks over, extruded in ...
Bottom is over-extruded or z-offset is too low, top surface is over-extruded, and the filament is either wet or needs retraction tuned.
dull hatch
Did you follow the print settings in the guide? The wall should be closer to 0.4. What you have is probably caused by having the Precise wall setting turned on.
mortal shard
I wasn’t aware of the print guide. I’ll try it again without precise walls. Is there anything else I need to modify?
dull hatch
I wasn’t aware of the print guide. I’ll try it again without precise walls. Is t...
Read the guide, it's all there.
mortal shard
Ok thanks
mortal shard
The results are way different now. Those little posts are stuck, but it might just be because the bed was too close to the nozzle. I had to do that though because it was under extruding a bit on the first layer so I had to push it down a little further to get it to stick. The little posts are messed up, not because of part cooling, but they are under extruded if it is hard to see in the picture.
I think I need to tune pressure advance but I don’t think that’s all of the problems
opal kiln
you can turn off PA to make sure everything slse is ok
how thick is the inner wall now?
also looks like you got some warpping
mortal shard
Ya I think it is because of the under extrusion. I’m using a textured pei plate at 60c
opal kiln
what was the inner square wall thickness
mortal shard
I’m using the rookmk1 that I built and I have calibrated the e steps. Also, I’m using Marlin if you’re wondering.
opal kiln
so i would just do a quick check mark 300mm on the filament and exturde 300mm and see how close you are to the mark
nice little printer 👍
opal kiln
300 is always a good test after the 100mm cal
mortal shard
How precise does it have to be? Can the smallest error make a big difference?
opal kiln
as you would if you were printing
mortal shard
Ok 👍
opal kiln
can you also post your last 3mf file of the test print too
mortal shard
Sure
1 sec
here
this profile is the premade ldo room mk1 profile but i changed the speed and some other things like an aux fan because i have one on my printer
opal kiln
im guessing in your marlin config your steps/mm for x and y are the same
mortal shard
yes they are
opal kiln
how is the 300mm extrude test going
mortal shard
I extruded through the hot end but on my LCD display it extrudes pretty quickly probably faster than I’ll ever print. It did under extrude a bit, but that might be just cause it’s pushing so much plastic through the nozzle. I need to somehow extrude at the right speed.
Under extruded by about 3 mm
opal kiln
you should be able to set the speed
mortal shard
I don’t really know if this is too fast
opal kiln
do you have a pc connected you can send the command from there
opal kiln
can you see on the screen the sxrtrusion speed
mortal shard
I can change the maximum extrusion speed
It’s at 25 mm/s right now, but I don’t know if that’s actually how fast it’s extruding
opal kiln
if you can change volumectri rate set to 10^3mm/s or speed set to 5mm/s
opal kiln
It’s at 25 mm/s right now, but I don’t know if that’s actually how fast it’s ext...
thats a bit fast
mortal shard
I did a max volumetric speed test and it was around 14 mm3/s
opal kiln
your printing the test part at 5.6mm/s
opal kiln
thats travel speed not extrusion speed
mortal shard
So I should set it to 5 mm/s for the estep test
opal kiln
or 7 if you want a bit if head room
mortal shard
Ok sounds good 👍
opal kiln
this is just to make sure the foundation settings are corrrrect
mortal shard
The extruder and hotter and combo didn’t really have a problem with pushing the filament through at 6 mm/s but it did under extrude a bit. Is it from the extruder slipping?
opal kiln
you will need to work that out
start with the filament just going from the reel straight to the ectruder
mortal shard
There are teeth marks from the extruder on it so I think it’s gripping well and also if I try to hold the filament well it’s extruding I can’t feel it slipping at all
opal kiln
maybe there is some frinction in the ptfe tube route
opal kiln
1mm slipping per 100mm of extrusion is too much
mortal shard
Should I tighten the extruder and try again?
opal kiln
if there is teeth marks on the filament its ok i think
mortal shard
That’s kind of what I thought too. The teeth marks are not too deep, but they’re also not too shallow.
Actually, I just noticed there looks to be a bit of grinding happening at the end of the filament
Not really sure what caused that
opal kiln
if you try the fiament straight in the extruder and extude 300mm is it ok
mortal shard
I think my tension on my extruder is really loose. I thought I tension it correctly.
Hopefully, I didn’t waste all your time just for a unproperly tension extruder🤣
opal kiln
if you dont know etc etc
mortal shard
Never mind, it was tension
Properly
If anything, it was too tight
I think the reason it grinded is because I inserted the filament wrong
opal kiln
when your done do the 300mm extrude again to make sur e
mortal shard
The very top of the hot end in the cold zone got a bit of plastic in it so I just had to clear it out that’s why the extruder was grinding. Luckily nothing too bad happened.
mortal shard
Depending on my extruder tension, the results will be different every time. Are you sure you’re supposed to calibrate E steps while pushing filament through or do you use flow rate in the slicer to do the final touches
opal kiln
the tension should have little effect on the amount extruded
you need to get the steps/mm very accurate this is a fundimental setting
dull hatch
The results are way different now. Those little posts are stuck, but it might ju...
Your z-offset is still too low.
mortal shard
the tension should have little effect on the amount extruded
Should it really be this hard? I’ve tried the 300mm test about 5 times and it’s not very consistent
I think I will try another day
Thanks for your help😊
dull hatch
I would do it all the way through the hotend, with the nozzle removed, at an extrusion speed of 1mm/s, and get it accurate to within 0.1%.
opal kiln
Should it really be this hard? I’ve tried the 300mm test about 5 times and it’s ...
it should be accurate , thats the point, it that isnt accurate then you will keep getting odd results and then you will be chasing your tail
how far out is your 300mm
opal kiln
@mortal shard stick with it the results will be worth it in the long run
mortal shard
Usually around 10mm under extrusion when in pushing it through the hot end when it’s hot and melting the plastic, but when I’m just pushing it through the extruder with no Bowden tube it over extrudes by about two or 3 mm
opal kiln
That's quite a difference do you have any tight corners?
mortal shard
I don’t think. Right when the filament enters the hot end, the cold part there is a little bit of resistance, but not much.
Do you think I need to tension my extruder
I don’t really know how much is too tight
pure ice
also, if you put the temperature up, would the extrusion distance change? like 20C more? those E3D nozzle has awfully short heatblock, just to test just in case, also, are those 2mm ID? or 1.9mm?
mortal shard
I don’t know. it’s a triangle labs tchc tr6 B
pure ice
I don’t know. it’s a triangle labs tchc tr6 B
Ah ah. Thought it was the Revo cause the red round sock.
Might as well try to crank up the temperature and see if the difference is less?
mortal shard
I’m printing at 220 C is that enough?
mortal shard
I am probably setting my extruder tension wrong but I’m not sure how to get it Perfect. A lot of people on YouTube say different ways to do it.
mortal shard
Quick update I was pushing filament through the hot end by hand and increasing the temperature from 220c to 225C made a huge difference in how easy it is to push through I didn’t know it was that big of a difference maybe printing at higher temperatures will work a bit better because this hot and uses a tiny ceramic heater
But the temperature doesn’t really drop down that much on the LCD display. It usually never goes under 1° below when extruding a lot of filament.
opal kiln
Quick update I was pushing filament through the hot end by hand and increasing t...
well done on finding a solution
mortal shard
I think I just need to do a bunch of testing
What do you think a good base extruder tension is for a BMG clone?
opal kiln
What do you think a good base extruder tension is for a BMG clone?
if there a teeth marks in the filament i wont be far off
if you ever do an upgarde and you didnt mind a bit more mass on the x axix go for a direct extruder
mortal shard
Ya I love direct drive😄
I have a Sovol sv06 plus with a direct drive extruder and it work amazingly
pure ice
Quick update I was pushing filament through the hot end by hand and increasing t...
Yea. I suggested that because until I have my first bowden printer after 2 Direct drive. I notice that a little temp bump helps a lot, especially if you have a weird filament path (mine) or thermistor somewhere that not reporting it perfectly (could be low).
It can simply be your thermistor in the hotend sits a bit far from actual amount of heat that the whole hotend takes, like mine (too close to heat source and right next to it, so the other side of hotend is not the same temp. And my filament path is bended at the hotend 90⁰.
Also personally it looks like the tube is a 2mm ID? Most of the white one is. I suggest to swap to the Capicorn XS, and have it slightly longer (even like 3-5cm). It looks like you have a pretty high restriction at the X0YMax positron. Bowden doesn't like it very much.
mortal shard
Thank you so much for your help 😁
It mostly under extrudes after retractions so that could probably be the Bowden tube
It also under extrudes a lot on the box on the Benchy. I don’t think my retractions are set correctly in this print but other ones that I have printed with good retractions still have problems, especially here.
pure ice
It also under extrudes a lot on the box on the Benchy. I don’t think my retracti...
Yay. Another one I could help, maybe!
Use the normally unused settings of detraction! If you retract like 1mm (I suppose you can get away with it due to short tube but not sure if your 2mm ID could do 1mm, my ID 1.9mm can, about 300mm tube or so) give it like 0.05-0.2mm (test it) Extra length on restart.
I suggest to cut the 1st 8mm bottom of the benchy, set top layer to 0. To tune your PA (if you print fast) you'll see a whole world of issue that way, also the seam, where retraction is would show as well.
Then use the top of the benchy to dial in your overhang
dull hatch
It also under extrudes a lot on the box on the Benchy. I don’t think my retracti...
That filament looks incredibly stringing. I think you need to dry it before doing anything else.
pure ice
That filament looks incredibly stringing. I think you need to dry it before doin...
That too. But tbh, I have some cheapo but extremely reliable (OD wise very stable I check) PETG and it strings like no tomorrow on my DD printer. Even with a good drying and drying while print of my Sunlu E2. Dropping temp also doesn't help much. Even dial down flow to not having it collect on the nozzle.
But I still manage to use up 5kg of it to print my filament stacking rack.
Out my 30 different brand and filament. Only that one has it.
dull hatch
That too. But tbh, I have some cheapo but extremely reliable (OD wise very stabl...
I have had a couple rolls of PETG like that too, from one specific brand...I got them for free, but will definitely never buy any filament from them.
mortal shard
Perfect! Jk
pure ice
I have had a couple rolls of PETG like that too, from one specific brand...I got...
I am actually super glad. 3kg for about $10. I was dreadful not know what to do with it
pure ice
Perfect! Jk
That looks a bit tooooo long lol. I mean original + some more. Just make sure at the furthest end it doesn't seem to bend both end. Nearly straight is enough.
That length for that bed you'll have one hell of slow print ha ha
pure ice
Lol. I knew it. Yea. That looks plenty good)
mortal shard
That filament looks incredibly stringing. I think you need to dry it before doin...
Well, I guess I better get to drying 🤣 i’ve done this before and It works surprisingly well.
pure ice
Well, I guess I better get to drying 🤣 i’ve done this before and It works surpr...
Ohhhh. If it PLA and strings like that you sure need to dry it!
Anyway. After. Use PA test, put in your outer wall speed and accel. Then use that to print your 8mm bottom of benchy without top layer. Save tons of plastic while dialing in different tuning. Try different Extra length on restart - this to fix seam gap. Note: you want it with PA already in place so not to void the result.
Then cut the benchy top off, where there is 4 columns and the roof. This will help actually dialing in your retraction a lot better. Increase the extra amount if needed if you have missing at seams when you got your retraction tune up.
This is how I cut and use the 0 top layer for the bottom piece btw.
Of course only to show. I test the bottom first to dial in the extra length + retraction + wipe on my bowden + Adaptive Pressure Advance (wrong one the inner wall and infill turn to pooopooo).
Then I test the top for retuning retraction, extra length, overhang speed+cooling, and smallest layer time (smoke stack should keep shape and not melted). Basically got a lot of small things done and save plastic and time to not having to print the whole boat.
If top of the roof missing a lot. It's always PA)
pure ice
I have had a couple rolls of PETG like that too, from one specific brand...I got...
And tbh. The rest of their filaments are just gorgeous, from the PETG-CF and ABS, ASA, PA, PLA-filled - anything basically, I daily print their PETG-CF and GF due to how stable they are. Except the PETG-ECO - which... I guess that where the problem comes from. ECO in there probably stand for organic wine, which, without the sulfur, is not much wine is there, if the smell is... wrong.
mortal shard
This is how I cut and use the 0 top layer for the bottom piece btw.
Of course ...
Thank you!
mortal shard
What is a good layer time? I’ve never adjusted this setting so I don’t really know what it does
pure ice
What is a good layer time? I’ve never adjusted this setting so I don’t really kn...
Tbh. Layer time. Shortest is some seconds that your cooling fan can keep up. And longest is... Tbh. Idk, depends on plastic. But half-plate worth of part won't crumble is a good start. So I would say... 30s-60s? Depends on which filaments (PLA close to 60, ABS close to 30)
In short. Too long per layer > plastic below cool down way tooo much (some doesn't care, like TPU, or less so, like pla, petg). Too short layer time > your last layer still tooooo hot. And some plastic doesn't like it. Either melt down, or droop, or not sticking properly
dull hatch
What is a good layer time? I’ve never adjusted this setting so I don’t really kn...
Fully depends on the material, and how strong you need the layer adhesion to be.
The longest it should be is how long it takes for the filament to fully cool on its own with just the ambient air temp.
mortal shard
I can never seem to get pressure advanced tuned perfectly. It always seems to under extrude a little bit after it takes the corner. Is this normal?
opal kiln
I can never seem to get pressure advanced tuned perfectly. It always seems to un...
then your PA value isnt correct
mortal shard
I’ve changed it multiple times and around 0.1 seems the best but it’s not perfect
opal kiln
I’ve changed it multiple times and around 0.1 seems the best but it’s not perfec...
0.1 seems very high, do you have a direct drive or bodem
mortal shard
I have a Bowden and it’s tube is around 350mm long
opal kiln
I have a Bowden and it’s tube is around 350mm long
if you turn PA off, what is the result like?
you can just print a 2 layer wall cube no infill no top to test
mortal shard
I did a pa test and around 0.1 looked good
But when I turn off pa some corners are overextruded and some walls are under extruded. But with pa set to 0.1mm the corners look a bit better but the walls are still under extruded. I’ve calibrated by E steps and done flow testing. I’m really not sure what to do now I’ve tried almost everything that I can think of.
It might be the speed I’m printing at, but I’m printing at 150 mm/s which isn’t too fast and I have a triangle labs TCHCTR6 hot end with a triangle labs BMG clone extruder so that shouldn’t be the problem.
This is with pa off
mortal shard
Pa?
opal kiln
ok print a square 20mm x 20mm 5mm high 3 wall no infill or top layers, as you got to 0.1PA try the cube with PA values 0.05, 0.15, 0.2 and 0.25 see if the error shifts around the corner
this will give you a point to tune too
bowden's can be tricky to tune
mortal shard
bowden's can be tricky to tune
ive figured that out 🤣
i think i need to increase my retractions from 1mm to 1.5mm because it is a bit stringy
opal kiln
can your hotend cope with 14^3mm/s?
mortal shard
I also did a max flow rate test and a safe value I got was 14 mm/s
opal kiln
you inner to outer speeds have a big difference in volumetric rates you may find keeping them similar speeds will help
mortal shard
o good to know
opal kiln
I also did a max flow rate test and a safe value I got was 14 mm/s
what di the max flow go too?
mortal shard
i forgot you can check that🤭 it went to 14.13 maby a bit much
it should be fine i think and the section with all of the gaps only went up to 13
and some other sections that went to 14 seem fine
maby i need higher temps? im printing at 220c
opal kiln
so if your max was 14^3mm/s your safe limit is around 10^3mm/s
mortal shard
i set my max i bit lower to be safe
opal kiln
if you "max flow rate " test toped out at 14 you need to set it to 10
opal kiln
if you set the Max flow to 10^3mm/s , that will limit the max flow rate maybe change the sppeds to be all 100 for now
except small permimeters
opal kiln
would exeleration and jerk need to be changed?
leave them for the moment
mortal shard
ok
mortal shard
You can see right after it does a travel move it under extrudes on the first line that it extrudes. Maybe I need to add some extra length on restart?
It is still under extruding
There’s just a line of under extrusion through the print for some reason
opal kiln
did you try the box prints yet?
opal kiln
i wont be online tomorrow but ill pick it up the next day , or Mxbrmr may help you out
