I would like to print the model of a house (as in the picture). I tried to print it, but it failed when it reached the roof. Spaghetti appeared and the model no longer stuck to the base. I guess this is because the model is completely hollow.
Basically it needs at least a brim, if not a raft.
Besides, how could I generate supports only inside the house so that the roof prints correctly?
Use support painting, and paint the inside of the roof. That should do the trick for you. But you sure are going to end up with a long print and a lot of supports. With that model, I’m not sure what else you could do. Too bad it doesn’t have a steeper roof, which could be printed without supports.
I just thought of another solution. Cut the roof off in the slicer, and orient it standing up, with the chimney at the edge being on the print bed. Use supports to support the other chimney. Use a generous brim (not auto brim, I would just make it something huge like 15 or 20 mm.) Then when it’s all done, glue the roof on with CA.
Thanks for your replies. I’m rather new to 3D printing with Bambulabs. How can I cut the roof off in the slicer?
There is a cut tool in the top toolbar. Click on the model and it will show up. It looks like this:
It will present you with a plane that you can move around and you can choose which parts you want to keep and what you want to do with them. Once you make the cut you can use the rotate tool to orient the roof. Then add your supports for the roof as needed.
If you would like some help I would be happy to set this up for you and post the 3mf file assuming the forum allows you to post that kind of file type. You just need to post the stl file here.
I can also try to post screen shots of my process to show you how I did it.
Thanks very much for your help.
Actually the file can be found here:
There is a version of it split into different parts, including the roof as a separate piece. But I would like to be able to print it as a single piece…
Interesting, following - looks like some printed without support.
Could it be possible for you to set the file up (main body of the house and roof separated, with supports for the roof only)? I’m trying to do that, but I fear I’m not a pro at it…
I’ve managed to cut the roof as you mentioned and, after many efforts, to lay it down on the plate.
But when I “Preview” the file, Bambu Studio adds supports everywhere, even on the main body of the house (where they aren’t really needed)…
I thought about this some more.
Taking into consideration that other people seem to be printing this without support, and the fact that you would rather print it as one piece, I am thinking maybe you should give it another try as one piece, just use a healthy brim to keep it from loosening from the bed. (I would personally give it a good 15mm.) You said you had spaghetti and that it came loose from the bed. So maybe the roof would have printed fine if it had stuck to the bed.
To make the roof work better, one thing you can do is to slow down the overhang speed.
What we don’t clearly know is whether they printed the multiple-part house or the one-piece version…
Anyway I’ve tried putting the cut roof onto a new plate. But I get an error message:
Try this.
Have you tried the Print Profiles? The idea is that the whole model and all the associated settings for it to work will be loaded.
Thanks a lot!
I will have to wait till next weekend to print it out though.
I have not thought about that.
In fact, I have done some flow calibration for the filaments I use. I also have a WhamBam plate, so adjustments also have to be made (bed temperature, cooling).
You can adjust to your specific requirements once you load the print profile. But honestly it’s better to run how the profile was setup (assuming it was from the model creator). They put time and effort into getting the profile to work. Printing like this will give you a baseline to reference from. Then you can add a different print plate to see what needs to change to use it. Once you have this dialed in, then tweak the filament for optimum flow. It’s an iterative process.
If someone new to 3d printing makes all the changes at once it is very hard to track down what is causing the actual issue(s). This is such a common problem that has plagued new people to 3d printing. They change a bunch of things or perform “modifications” before really learning and understanding how their stock printer runs and functions.
What about flipping the model upside down? You would still have supports for the roof, but they would be quite a bit shorter.
A good thing to know for that print is the overhang capacity for different layer heights. The Standard 0.20 mm height can do about 45° overhang. Going down to 0.16 mm height, you can do 53° (counting 90° as a bridge). At 0.12 mm you can do 60° and at 0.08 mm you can do almost 70°. If you want maximum overhang capacity without hacking extruder settings, you can use wider lines: At 0.08 layer height and 0.88 mm line width (which is perfectly fine with a 0.4 Bambu nozzle due to its shape) you can theoretically do 80° overhang with no supports.
The larger heights are poor with overhangs by default, can’t even do 45°. They really should default to a line width of at least double the height. But if you set them to a full 1 mm line width (yes, that too is perfectly fine with a Bambu 0.4 nozzle, provided layer height is at least 0.20), you can do 64° with 0.24 and 61° with 0.28 mm height. This will also print very fast, mostly bound to the filament’s max volumetric flow.
Note that you need Orca Slicer, or the latest 1.8 beta of Bambu Studio, to set the full 1.0 mm width due to a bug in BS 1.7. But if the slicer erroneously complains about it, just set it to 0.999 instead.
Edit: Oh, and TLDR; you can try Variable Layer Height and Arachne wall generator - that should ensure good overhang capacity where needed, and speed otherwise!
I might just as well mention this: For the ultimate overhang capacity, edit your extruder settings to allow 0.04 layer height (i.e. 10% of nozzle height). Then use that with a line width of 0.84. This yields a whopping (theoretical) 85° overhang capacity. At this end of the spectrum, the maximum speed is bound to printer’s max. of 500 mm/s (where it will push only a tad over 4 mm³/s). I’m not sure if it’s feasible to print much at extreme settings like that, I’m planning to test it.
Please let us know. This is the first time I have seen calculations like this and it’s fascinating. I just printed something yesterday based on your post and it worked like a charm. I had a steep overhang angle and used variable layer height to set the critical layers to .1 layer height and it printed so clean. Thank you.
OK so I tested my figures and reality is well in parity with theory. Please note that these results are not perfected at all - they were just quick tests without tweaking cooling or speed. I’m using latest beta of Bambu Studio.
First off, here’s basically the “0.08 Extra Fine” system preset with a 0.4 nozzle. My calculations indicated “almost 70%” and that is indeed when things start going bad:
And here’s using Variable height (with default extruder settings, so 0.08-0.28 mm) and Arachne wall generator tweaked for allowing line widths between 0.12 and 1.00 mm. Not only is it capable of the 80° I suggested, it also speeds up the print from 41 minutes to 16 minutes:
I’m pretty sure I can make them look better than this with some tweaking. I’m home enjoying Covid-23 right now so I might post more results tomorrow.
