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The Everything 3D Printer Thread

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JackOfDiamonds

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Since I got my printer (Sidewinder X1) it has always shown these stepper motor patterns on shiny filament. These are what Prusa is calling "VFA" or "vertical fine artifacts" and they are caused by the stepper motor vibration / cogging (the printer also has other artifacts like ringing, but that's another story...) These VFA's are on every shiny print and correspond perfectly to the stepper motor frequencies. In my opinion, these are endemic to all normal printers, and can be seen on practically all prints if you just print shiny filament and use the right lighting. They are impossible to feel, so it means they are only a few thousanths at most, and don't impact function, but unforunately 90% of my printing is on shiny PETG and I'm just tired of seeing them. They appear to be endemic to all cartesion 3Dprinters, but only show up if you use shiny filament and your printer is otherwise tuned well.

There was a big effort to address these on the Prusa Mk3 with no sure fix, and they have been newly addressed on the Mk4 by Prusa using the most advanced Trinamic drivers and trying different waveform patterns (apparently the latest Trinamic drivers contain multiple alternate waveforms for tuning) with some results. My printer already has Trinamic 2100 drivers with StealthChop, which tells me that I probably can't address these with stepper drivers, and need to do something different. The problem seems to be there are only about 5 full steps per mm, which is "just enough" resolution for 3D printing, and although running 16x microstepping and StealthChop smooth things out a lot, apparently not enough.

I was curious if gearing down the axis would help, so I put in a 3:1 gear reduction on the X axis that simply bolts on in place of the factory stepper. The same belt and mount is used, only needing to update steps/mm in firmware (no need to reflash firmware). This takes the axis to 15 full steps per mm. It did help, as you can see below, and I think I'll do the Y axis next. The downside is I had to reduce my travel move speed from 200mm/s to 80mm/s for reliable operation, although I think I can tune this back higher. And, there is a real chance the higher stepper speeds will introduce new resonances due to the higher RPMs it is now running, although time will tell. This is also working my 8bit board harder, since the stepping frequency is now tripled and soon will be 6x-ed, although I normally print slow like 20-40mm/s anyway, since PETG prints better slow IME.

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XJSuperman

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Well here's a fresh example:
Mini clip: a sunglasses holder that goes on your car visor. I stopped it after a few minutes and could see what was happening.
Bambu petg basic black. Bambu default process and filament settings.
It has been in the dryer for a few hours at a time, RH read 38% when I pulled it out to try it. I think I will try and start it tomorrow morning before work and see how it looks when I get home. I just didn't want to leave it run while I was gone all day. The filament had not really gotten below 38 in any of the drying runs so I figured that was about as good as it gets.
Stringy, breaking and balling up.
20240514_194140.jpg20240514_194051.jpg
Screenshot_20240514_195017_Bambu Handy.jpg
 

XJSuperman

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Dryer showed 30%RH this morning after running several hours. I reset and its running all day today. Once home I'll try another default print and then move to slower speeds if needed.
 

MadeByMiller

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Well here's a fresh example:
Mini clip: a sunglasses holder that goes on your car visor. I stopped it after a few minutes and could see what was happening.
Bambu petg basic black. Bambu default process and filament settings.
It has been in the dryer for a few hours at a time, RH read 38% when I pulled it out to try it. I think I will try and start it tomorrow morning before work and see how it looks when I get home. I just didn't want to leave it run while I was gone all day. The filament had not really gotten below 38 in any of the drying runs so I figured that was about as good as it gets.
Stringy, breaking and balling up.
20240514_194140.jpg20240514_194051.jpg
Screenshot_20240514_195017_Bambu Handy.jpg
I would let the filament dry no less than 24 hours straight at 65C. It will be fine to run unmonitored. The default setting should work just fine, but always change to gyroid infill pattern instead of grid (although I agree this is a 100% infill part). Speeds shouldn't be an issue for the default Bambu PETG filament profile, but you can try setting it to Generic PETG which will slow down all the speeds. I know there's some naysayers when it comes to drying, but I'd be shocked if it's not the root of all of your problems here.
 

XJSuperman

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I would let the filament dry no less than 24 hours straight at 65C. It will be fine to run unmonitored. The default setting should work just fine, but always change to gyroid infill pattern instead of grid (although I agree this is a 100% infill part). Speeds shouldn't be an issue for the default Bambu PETG filament profile, but you can try setting it to Generic PETG which will slow down all the speeds. I know there's some naysayers when it comes to drying, but I'd be shocked if it's not the root of all of your problems here.
Well that's half the issue with the dryer so far then. Its set to 51C right now. What no one has mentioned is what the RH% should read when its "dry".
I've read about the gyroid pattern and was attempting to use it early on, but quit worrying about it with all the other changes in the previous tests. Just have to get through the workday to try the next steps. I will admit this is quickly turning me off from PETG. If I didn't need something to handle temps/elements and hadn't purchased several rolls, I'd be done with it. This roll must have been rescued in a deepsea dive lol.

Speaking of infill patterns....has anyone tried the new CrossHatch method yet? Studio just got a huge update the other day and that was included.
 

MadeByMiller

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Well that's half the issue with the dryer so far then. Its set to 51C right now. What no one has mentioned is what the RH% should read when its "dry".
I've read about the gyroid pattern and was attempting to use it early on, but quit worrying about it with all the other changes in the previous tests. Just have to get through the workday to try the next steps.

Speaking of infill patterns....has anyone tried the new CrossHatch method yet? Studio just got a huge update the other day and that was included.
I don't base my drying off humidity percentages, just time, but I currently have two spools of PETG drying in my Sunlu S4 and the screen is reading 15% RH. The dryer has been running for about 18 hours so far. The filament was brand new, I pulled them out of the vacuum sealed bags just before I stuck them in the dryer.

Hadn't heard about crosshatch until now, but it looks interesting. I use 3D honeycomb on a lot of parts and it's similar from what I can tell. I would absolutely try this over grid. Self intersecting infill patterns can be a massive headache.
 
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jeepxj

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I would let the filament dry no less than 24 hours straight at 65C. It will be fine to run unmonitored. The default setting should work just fine, but always change to gyroid infill pattern instead of grid (although I agree this is a 100% infill part). Speeds shouldn't be an issue for the default Bambu PETG filament profile, but you can try setting it to Generic PETG which will slow down all the speeds. I know there's some naysayers when it comes to drying, but I'd be shocked if it's not the root of all of your problems here.

explain why its just infil and not the whole print if its not dry enough?
 

MadeByMiller

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explain why its just infil and not the whole print if its not dry enough?
I disagree that it's only infill, it looks like the walls are pretty trash too.

Looks like pretty bad oozing/stringing too which are trademark signs of wet filament.

The remarks above are in regards to @XJSuperman 's print. As far as your photos, I would attribute most of that to grid infill. Grid infill especially ***** with PETG because it's so prone to sticking to itself and the nozzle while printing.
 
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jeepxj

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I disagree that it's only infill, it looks like the walls are pretty trash too.

Looks like pretty bad oozing/stringing too which are trademark signs of wet filament.

The remarks above are in regards to @XJSuperman 's print. As far as your photos, I would attribute most of that to grid infill. Grid infill especially ***** with PETG because it's so prone to sticking to itself and the nozzle while printing.

wouldn't wet have string on the inside of the arc here?
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XJSuperman

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The update you are all ready to be done with! I was able to print the aforementioned Mini clips successfully! They look really good to me actually. So I am trying the bigger more important print that started this mess now. Already had one failure right away so I slowed some things down a bit more and we are about to find out how that goes.
Drying 8hrs while I was at work at 51C, then 2 more hours at 65C. That got me down to ~20%RH from what was at one point (not this morning) 45%RH. I think I may move to another brand of PETG after I use the last of this stuff. Unfortunately it was Bambu from Bambu. Ordered with the printer originally.
20240515_194517.jpg
 
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moab11

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This is the Bambu Lab filament guide, they recommend drying PETG for 8h at 65C.
I dry all of my filament for at least as long as listed in the guide and store with printed desiccant holders and hygrometers. The hygrometers all seem to bottom out at 10%RH and I try to keep them there.
 

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MadeByMiller

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The update you are all ready to be done with! I was able to print the aforementioned Mini clips successfully! They look really good to me actually. So I am trying the bigger more important print that started this mess now. Already had one failure right away so I slowed some things down a bit more and we are about to find out how that goes.
Drying 8hrs while I was at work at 51C, then 2 more hours at 65C. That got me down to ~20%RH from what was at one point (not this morning) 45%RH. I think I may move to another brand of PETG after I use the last of this stuff. Unfortunately it was Bambu from Bambu. Ordered with the printer originally.
20240515_194517.jpg
Glad to see you had success! Reach out any time if you have another printing issue. I wouldn't put any blame on Bambu for having wet filament. PETG can and will absorb moisture during the manufacturing process. Filament is actually cooled with a water bath post extrusion, so it's extremely common to have wet filament straight out of the vacuum sealed bag. I exclusively use Atomic PETG filament, as it's high quality, US made and they have a broad range of colors. As I mentioned before, I always dry before printing.
 

XJSuperman

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Figured as much, but always have to check. It's odd that you are having so much adhesion now. Maybe @jeepxj has some pointers then.
Tbf, PLA doesn't do this. Just PETG. And it has since the first test prints a couple weeks ago. That first layer or two is really stuck good. I probably just need to drop the bed temp a hair, but wanted to hear other's thoughts.
 

jeepxj

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i run 70c first layer. 82 to 86 for bed temps.

you cleaning the plate good? dove soap. warm to hot water. paper towel scrub.
 

MadeByMiller

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The large print made it as well.
Two problems:
-The overhang layers are a little rough. Need to look into that.
-petg sticks a little too well to the pei textured bed plate. Ready had to dig to scrape it clean. Popping the part off the plate may be damaging on other parts.
Lets see a photo of the overhangs. Anything over 50* is going to struggle. You can try adjusting cooling settings, but it's tricky.

Weird that it's sticking so hard. I've had that problem with PETG-CF before, but never standard PETG. It always pops right off. You can always wipe down the build plate with window cleaner prior to printing, but this shouldn't be necessary.
 

XJSuperman

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i run 70c first layer. 82 to 86 for bed temps.

you cleaning the plate good? dove soap. warm to hot water. paper towel scrub.
Lets see a photo of the overhangs. Anything over 50* is going to struggle. You can try adjusting cooling settings, but it's tricky.

Weird that it's sticking so hard. I've had that problem with PETG-CF before, but never standard PETG. It always pops right off. You can always wipe down the build plate with window cleaner prior to printing, but this shouldn't be necessary.
I'll have to check the settings at home later and get pics, but my temps should be very close to defaults. Maybe bumped up a few degrees. No, I am not cleaning the plate much. I keep it wiped and scraped free of debris but I haven't been wiping it down or washing it because I wasn't having problems getting things to stick. And I'd think that a dirty plate would make things stick less, so this PETG sticking so well is interesting.
 

XJSuperman

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Home and the values are:
Nozzle temp: 260C for all
Bed temp: 80C for all
Pics of what I am calling overhangs (maybe theres a better term?)
20240516_172821.jpg20240516_172832.jpg20240516_172840.jpg20240516_172857.jpg
The first pic is the overall part in its normal orientation. I laid it on its back you can see the difference in layers for the fileted edge between bottom and outer walls. Also note the bad spot on the bottom. It seemed to recover so I kept the print going. (I'm calling it moisture as well since I could have dried it a little hotter longer)


Also, I need to step back and quit having little issues, I feel like I'm hijacking this thread for the rest of the good folks here with info and models to share.
FYI, the crosshatch pattern was quieter and seemed to work well.
 
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MadeByMiller

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Home and the values are:
Nozzle temp: 260C for all
Bed temp: 80C for all
Pics of what I am calling overhangs (maybe theres a better term?)
20240516_172821.jpg20240516_172832.jpg20240516_172840.jpg20240516_172857.jpg
The first pic is the overall part in its normal orientation. I laid it on its back you can see the difference in layers for the fileted edge between bottom and outer walls. Also note the bad spot on the bottom. It seemed to recover so I kept the print going. (I'm calling it moisture as well since I could have dried it a little hotter longer)


Also, I need to step back and quit having little issues, I feel like I'm hijacking this thread for the rest of the good folks here with info and models to share.
FYI, the crosshatch pattern was quieter and seemed to work well.
Drop the bed temp down to 70C for all layers, that should solve the over adhesion issue. The overhangs actually look good for what they are. It's a bad idea to add fillets to your parts in the Z axis like that, instead you should be using a chamfer there. A chamfer is a constant, linear stepover, while a fillet radius in that orientation is starting off at a very long stepover (sometimes more than one extrusion width) and narrowing up as it goes up the radius.

I made a quick sketch in Fusion to illustrate what I mean:

Chamfer VS Fillet.jpg

I think you sharing here is perfectly acceptable, for what it's worth. The thread is titled "The Everything 3D Printer Thread" after all. If you're not comfortable sharing here, the offer stands for you to message me any time on Instagram.
 

XJSuperman

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Drop the bed temp down to 70C for all layers, that should solve the over adhesion issue. The overhangs actually look good for what they are. It's a bad idea to add fillets to your parts in the Z axis like that, instead you should be using a chamfer there.
Sounds good, thanks for the help, EVERYONE, honestly. Yeah, I agree the chamfer would have been better, and honestly not necessary at all, but this wasn't my part file, and it is not for me. A friend wants it to put his spices in on his smoker. That's the file he sent, albeit with some serious re-scaling to get within sizing constraints. I should have just whipped my own up and been done with it, but that's what he wanted. We know what to change next time to simplify the process.
 
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