Sab-a-dab-a-doo! The back-country LJ build has officially started

Call me doubtful regarding this statement, Mike. I aborted my first full and final print yesterday after about 30 hours of run-time because one of the support towers warped and the print head knocked it off the build plate. I should have taken a photo, but was pretty disgusted and didn't think about it. That was with automatic tree supports with the style set to "Tree Strong". After some research on warping, I changed to automatic normal supports with the style set to Grid and slowed down the support speed to try to prevent the same thing. Look at the warping that's now occurring in the grid supports:
View attachment 662609

If ASA is this prone to warping, I don't think calibrating will solve the problem because warping in a part is very hard to model or predict. Like welding sheet metal, the temperature gradients causing the part to warp vary with the smallest change in conditions (like small drafts from environmental influences like a person walking by while you are welding). I suspect that the calibration only works with the print you used to calibrate. Repeat the part, and the calibration is no longer valid. That said, the same problem occurs when you change the model like I did.

I have to say that I'm getting very frustrated with 3D printing this part. I'll probably be aborting this print today, too. I need more rigid supports that won't warp as much (a lower surface area to volume ratio or more connections), but I can't find a way to do that. I thought the Grid option would tie the support walls together in a rectangular grid (from top view), but they are just zig-zagging back and forth with no ties at 90° to the walls shown. The part itself is much more rigid and isn't visibly warping, so I think if I can get the right support, it'll work. Do you know of a way to accomplish that?

Stay tuned for more frustrating sab 3D printing adventures!

Those supports are interesting. I’ve never had it make any that looked like that. I’ve probably not printed anything that tall either.

Mine have either been trees or blocks. Yours look like narrow thin columns.
 
  • Like
Reactions: sab and FarFire70
I know you want this to be one piece…but I really think you’ll be a lot happier, or at least have a part that is functional, if you split it into a couple of pieces.
 
  • Like
Reactions: sab
I meant the angle of the actual support pattern, not the threshold for support generation. You can also change the support pattern and spacing here as well. I frequently play with the angle and spacing, coupled with part orientation. Just for the record, I've never used the tree support type, I think everything has been "normal (auto)" to date, though I suspect there's additional power in the manual settings.

View attachment 662720

Oh, I definitely misunderstood. Those settings (especially the top one you circled) are more like what I was looking for. Oddly, the "Rectilinear Grid" doesn't really make a grid, but the Honeycomb option might give the support the stability I've been looking for. I've stopped my print and am going to try that option, so thanks for the idea!
 
...I really think you’ll be a lot happier, or at least have a part that is functional, if you split it into a couple of pieces.
The first part of your post won't ever be true because I have strong preference for this being a one-piece part. ;) However, the second part is looking like my only option. I definitely don't have any functional one-piece prints to speak of. 😔
 
@chili_pepper - thanks for the hot tip. This print, with honeycomb support, has been running for 10 hours and it's by far the most stable of all the prints at this point in the job. I suspect that now my challenge will be keeping the piece attached to the build plate because it's so much more rigid. Here are some pictures taken a few minutes ago:

IMG_8480.JPG


IMG_8481.JPG


These are my support settings (I circled the ones I changed for this print):
1766844214980.png


The one thing I'm worried about is eventual warping due to the crazy print time:
1766844334282.png


That's 10 minutes shy of a full work week for the old Bambu. :oops: What a little worker-bee that guy is. :ROFLMAO:

And I'm glad I bought the AMS HTs because I had to crack open a new spool of this white ASA and dry it while the print is running. It should be dry right about the time this current spool runs out, so I'll swap it into the AMS 2 Pro once it's done.

Thanks for sticking with me on this challenging (for me, anyway) project, and stay tuned for the exciting conclusion of this print job! If the excitement is another failed print, it's a two-piece, bonded design for me!
 
Oddly, the "Rectilinear Grid" doesn't really make a grid

I have yet to figure out what the point of this one is. I've now run two prints with that set as the infill type (accidentally), and it was the sole reason for print failure in both cases. Both times it collapsed on itself, I can't imagine it would be any good for support use but maybe there's an application somewhere. I tend to run finer print settings and a 0.4 nozzle, maybe it works better with thicker layers and larger nozzles.
 
I will just share (re-iterate) that I've adopted 'Gyroid' as my go-to infill. It seems more random and leaves less commonly-spaced 'voids' than other infills — and I fell the periodic voids don't offer the same strength as something a-periodic-'ish'.

I have not imperial data - but offer as a input.

Just food for thought.
 
I've adopted 'Gyroid' as my go-to infill.

I've never used this one, however, I recently discovered an interesting use for it. Admittedly, I only know enough about the slicing software to be dangerous and I don't typically download and print other people's designs. That said, I like clever designs no matter who came up with them. After I got my OG AMS unit, I set about designing some desiccant containers for it with a focus on function, fast printing and minimal material usage in design. I ended up with a set of flat print glue-up bins that have served well and met the design criteria.

After recently picking up two AMS HT's, I did a quick search for risers to elevate the units as I wasn't feeling much like designing one. While searching for the riser, I came across this desiccant bin...

_DSC0350.jpg


https://makerworld.com/en/models/1376675-ams-dry-pod-ultra-ventilated-light-8g-kit-card

These are snap together desiccant bins that print very fast and use minimal material...and incorporate the Gyroid infill pattern to create the ventilated mesh in the slicer, it is not modeled. I haven't had the time to go back and investigate further, but there's something to be learned from this design file for slicer noobs like me (and maybe you, too). I'd recommend a download and poke around the file whether you intend to print the bins or not. I actually printed a set to verify print times and inspect the finished items, and I have to say the result is kind of impressive. But the techniques used in the slicer... :geek:
 
With 6-1/2 hours to go, this print looks like it [CHRIS BERMAN VOICE = ON] could. go. all. the. way! [CHRIS BERMAN VOICE = OFF]

Overnight, the first deck went down on the support wonderfully, and a few minutes ago, the second deck was being applied successfully on another section of support:
IMG_8488.JPG


Supports still look plumb and level, with minimal warping (the "lumps" seen below are the tree part of the "Tree Hybrid" support style), and I never saw many "crumbs," unlike all previous prints using the ASA filament:
IMG_8487.JPG


The key was getting support that was rigid enough to survive the printing environment. I have to say that I'm disappointed, again, with Bambu. If their software was as good as I thought it would be, it should have realized that a tall support tower using ASA filament needs rigidity. I think I made three prints with ASA (it's all a blur), and after the first one, I knew my problem was structural because the base part, which is quite rigid, was printing just fine. There are so many parameters in the software, despite my searches, I didn't find the right one until @chili_pepper pointed me to the Base Pattern parameter. Even then, there was disappointment because "Rectilinear Grid" doesn't produce a grid. That's got to be a bug. That same style is used in other parameters, and in each of those, it does produce a grid.

That said, I'm still happy with the Bambu purchase. It's an amazing tool, but it still requires NI (natural intelligence). As someone who thinks AI will cause far more damage than any benefits it provides, that makes me :) !

This print's not done, yet, though, so I can't quite celebrate, yet. Stay tuned for the exciting conclusion of this project!
 
With 6-1/2 hours to go, this print looks like it [CHRIS BERMAN VOICE = ON] could. go. all. the. way! [CHRIS BERMAN VOICE = OFF]

Overnight, the first deck went down on the support wonderfully, and a few minutes ago, the second deck was being applied successfully on another section of support:
View attachment 662929

Supports still look plumb and level, with minimal warping (the "lumps" seen below are the tree part of the "Tree Hybrid" support style), and I never saw many "crumbs," unlike all previous prints using the ASA filament:
View attachment 662930

The key was getting support that was rigid enough to survive the printing environment. I have to say that I'm disappointed, again, with Bambu. If their software was as good as I thought it would be, it should have realized that a tall support tower using ASA filament needs rigidity. I think I made three prints with ASA (it's all a blur), and after the first one, I knew my problem was structural because the base part, which is quite rigid, was printing just fine. There are so many parameters in the software, despite my searches, I didn't find the right one until @chili_pepper pointed me to the Base Pattern parameter. Even then, there was disappointment because "Rectilinear Grid" doesn't produce a grid. That's got to be a bug. That same style is used in other parameters, and in each of those, it does produce a grid.

That said, I'm still happy with the Bambu purchase. It's an amazing tool, but it still requires NI (natural intelligence). As someone who thinks AI will cause far more damage than any benefits it provides, that makes me :) !

This print's not done, yet, though, so I can't quite celebrate, yet. Stay tuned for the exciting conclusion of this project!

Meanwhile, over in Nashville TJ’s 3D shop:

IMG_9018.jpeg


Nice work, Scott. Very cool that you kept after it. Amazing the help we all get here on this forum. Nice work to Chili as well.
 
I will just share (re-iterate) that I've adopted 'Gyroid' as my go-to infill. It seems more random and leaves less commonly-spaced 'voids' than other infills — and I fell the periodic voids don't offer the same strength as something a-periodic-'ish'.

I have not imperial data - but offer as a input.

Just food for thought.
FarFire70 - my problem wasn't related to an infill pattern. The base part, for which I used the Rectilinear infill pattern, always printed beautifully, and would have also printed beautifully with Gyroid, Honeycomb, etc. because they all give it rigidity to withstand the warping forces from the temperature differentials. My problem was caused by the support pattern, and the choices for support type don't include the Gyroid pattern. In fact, the only one that gives adequate rigidity is the Honeycomb pattern. Here are the choices:
1766931920536.png


That said, I think that both the Gyroid and Hilbert Curve options for infill patterns are best when you don't know what types of loads a part will see. If you know the loads, it makes sense to try to orient the part and pick the infill pattern to best resist the loads.
 
Glad to see the H2D is up and running, Jeff, but be careful not to get sucked into the void like I seem to have done... :ROFLMAO:

Amazing the help we all get here on this forum. Nice work to Chili as well.
Yup. This forum is very special, and I try not to take it for granted! A bunch of smart, like-minded fellers can really do some cool projects!
 
And I've jinxed myself by counting chickens while I still have eggs. I despise the fickle finger of fate!

Just after I posted that the print was going swimmingly, some issues presented themselves. Using the tree (auto) for the support Type and Tree Hybrid for the support Style was a mistake. I should have used normal (auto) and Grid, instead. The reason is that with tree supports, you still end up with very slender supports that aren't as rigid, and long prints with slender support is a bad recipe. I re-sliced using normal (auto) support, and there are no support sections that are slender. Oddly, the print time would have also been 5-6 hours shorter with normal (auto)! Semper discens...

Here's what's just occurred: at the back corner, where a mounting tab is located, I first started to see the main supports start to wobble. I think I've abated that problem by cutting the machine speed to 50% and super gluing the supports to the main part. I put the super glue in the gaps indicated with the red arrows in the photo below. However, shortly after that, the very small tree limb at the corner cracked and was displaced where the blue arrow is:
1766935960472.png


Since it didn't completely crack through, I was able to glue that, too (the photo was taken after gluing), but I'm really worried it won't survive. With the reduced speed, it'll be almost four hours before the deck is put on that section. The nozzle seems to catch it with each pass, like a tuning fork, and I'm skeptical the super glue is strong enough to survive 35 hits (that's how many layers to go until it's decked).

However, I have in mind a way to salvage this print, and I'm wondering what y'all experienced 3D printers think of this plan. As long as that mounting tab is the only damage and it doesn't cause the print to abort, I'll cut off the remainder of the tab, print a new tab with a mounting flange, use 27 clamps on the welding table to hold everything in place like I typically do, and glue the new tab on. So, as I've said several times, I may end up with a bonded, two-piece print after all. Thoughts? Will the bond be strong enough? It would be mainly loaded in shear, which is the best load case for a bonded joint.
 
I have to say that I'm disappointed, again, with Bambu. If their software was as good as I thought it would be, it should have realized that a tall support tower using ASA filament needs rigidity.

While I completely get where you're coming from and fully understand the frustration of failed parts from personal experience, I think you're giving the software credit for being smarter than it actually is.

Technically what you're paying for from Bambu is the printer technology and hardware, not the software. The app is an easy convenience item (which I have never used) and likely a Bambu creation, but if I'm not mistaken, the slicer is actually a fork of the Prusa slicer, which is a fairly well regarded piece of software as slicers go. Bambu has basically added the convenience of printer, nozzle and filament presets, along with the network monitoring features and print cloud access (if you use that, I do not). In truth, you could use any slicing software to generate your print code, though you would need to configure the slicer's settings to suit the Bambu printer specs.

I guess my point is the slicer is only as smart as its parameters allow it to be, and many of those parameters are user adjustable. It's essentially a graphic representation of the printer's CNC code with a nice UI to adjust the settings that effect the code. Bambu is just giving customers a starting point.
 
  • Like
  • Love
Reactions: Mike_H and sab
...if I'm not mistaken, the slicer is actually a fork of the Prusa slicer
You are correct. I found this a few days ago when poking around the Bambu Studio app (the Windows app, not phone app):
1766938806678.png


I thought it was interesting that, in a non-Chinese modus operandi, they gave credit where credit was due. My understanding is that most of the slicer code out there was originally open-source, and as the technology advanced and became more consumer-centric, that open source code was built upon with proprietary software by most of the manufacturers, creating the forks in the road to which you refer. Is my interpretation of the history accurate?
 
You are correct. I found this a few days ago when poking around the Bambu Studio app (the Windows app, not phone app):

I think the phone app is called Bambu "Handy", which is apparently also a slang term camp Germans use for their mobile phones as well as a reference to digital stimulation of the male genitalia. Either way, I have a hard time taking it seriously, not really into phone apps and have no interest in BL's cloud anyway. :D


I thought it was interesting that, in a non-Chinese modus operandi, they gave credit where credit was due.

I won't give BL too much credit here, but I feel like this situation is a bit different than most with regards to the stereotypical Chinese vs. IP situation. First it was the Chinese ripping off IP for Chinese use, but this eventually filtering into the global stream as more companies began using China as their start-to-finish manufacturing and logistics entity. Now it's a bit wild west, affecting large and small businesses alike as we've seen with copies of one of our member's billet soft shackle points as well as another's 3D printed cabin air filter housing. But in this case the core IP, the tech and hardware, is Chinese.

I figure if they were clever enough to develop these printers (and stage a bit of a consumer market coup in the process), they were probably clever enough to realize there was no point in expending resources reinventing the wheel when it came to the slicing software. They weren't going to beat anyone there so just tweaked the excellent foundation already available to suit. And given their 3D printing innovations and likely associated desire to protect them, I think you've got to give credit to others when and where applicable, you've got to play on the level.

Is my interpretation of the history accurate?

I can't speak too much to the history, I've only been dicking around with this stuff for about 2.5 years at this point.
 
Last edited:
  • Like
Reactions: sab
Well, the support that I super-glued has survived long enough for the deck to be laid on top, so I've crossed that hurdle:
1766945485070.jpeg


I sped the printer back up to full speed now, and it should be finished in under 4 hours. Stay tuned!
 
And Bob's your uncle:
1766969622861.jpeg


I'm very pleased with the results, especially given the effort it took to get here. All that's left is my attempt at dust seals for the cutting brake slots, but I'm not confident it'll work. Alas, that'll have to wait a few days. I'm going to go try to put some meat on the ground tomorrow and Tuesday in a cull hunt on a friend's beef cattle farm. I've been waiting (a long time) for some cooler weather because I don't like sweating when I hunt. There's a cold front moving in!

Stay tuned!