Bridge infill versus support
I have an opening at the bottom about 15*15mm, 2mm height. The height is critical and I want to avoid the bridge infill and add manual support instead. I can't get rid of the infill and I can't get the manual support to work. How do I do that with PrusaSlicer?
/ Lars
RE: Bridge infill versus support
Search for the movies on how to. On prusa website, and on youtube.
Load a model.
use only support enforces,
right klik on model, add support enforcer, use a box, in this box will support be used.
or use everwhere support, then make a box again, to blok support where you do not want it.
RE: Bridge infill versus support
It is really hard to figure out what you are trying to accomplish without a photo of the problem. But in general, enabling support enforcers and placing an enforcer where you want support is the best option. The enforcer must touch the surface you want supported, and there are X-Y constraints that need to be obeyed.
RE: Bridge infill versus support
Link to model (for some reason I can't add a picture) Dropbox link to model
Below "T3 T4" is the actual opening. The idea is to push another part into the opening.
I guess that it's the bridge infill that gives the rough surface. So the plan was to get rid of the bridge infill and add manual support instead. The bridge is at layer 20 with 0.15mm steps.
I can't find a command for skip bridge infill or getting the manual support working. I tried "support enforces only", "only infill where needed" and more but with no success
The support box was standing on the base and passing through top of the opening, ok?
Any other way to solve the problem? Printing upside down helps, but move the problem elsewhere.
RE: Bridge infill versus support
Under Print Settings > Support Material you need to turn ON Generate Support material but turn OFF auto generate supports. You can then add a support enforcer for the areas you want support in. You also need to turn OFF Dont support bridges so that the support will go under an area normally bridged. I have attached a zipped 3mf project with your model and the settings applied as an example for you to experiment with.
RE: Bridge infill versus support
Thanks!
Interesting, viewing the model there is a solid part in the opening, but if I view the layers, there is still problems. I will print your model this afternoon to see what comes out 😉
Thank you
Lars
RE: Bridge infill versus support
Unfortunately the bridge infill is still there. Also the printed support only cover a part of the added support box. Could it be some other setting overriding bridge and manual support?
RE: Bridge infill versus support
in Prusa Slicer 2 there is an option to not support bridges, have you tried switching it of
f?
it's an advanced option... so make sure you select advanced or expert... to see it
Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: Bridge infill versus support
Thanks for the tip, but no, the bridge is still there.
RE: Bridge infill versus support
Still trying to figure out what your complaint is... but if you can't figure out how to drag and drop an image into the forum, lol.
RE: Bridge infill versus support
The idea is to insert a holder into the opening
RE: Bridge infill versus support
What is it about the bridge infill you don't like? That it prints slower? That the extrusion size is a bit smaller? That the supported area is not dimensionally accurate? Or is it cosmetics?
RE: Bridge infill versus support
What is it about the bridge infill you don't like? That it prints slower? That the extrusion size is a bit smaller? That the supported area is not dimensionally accurate? Or is it cosmetics?
I believe the OP wishes to insert another piece into the recess, hence a recess without a droopy leading edge and rough inner surface.
If that is the case, I would suggest the OP consider reorienting the object.. pretty much any other orientation would give a better quality recess.
i3 Mk3 [aug 2018] upgrade>>> i3MK3/S+[Dec 2023]
RE: Bridge infill versus support
Yes John, exactly!
It's possible to rotate it 180 deg but that moves the problem to another area. Maybe i have to add some extra space experimentally for the "hanging wires"?
But I can't understand why it's not possible to turn of bridging and add manual support. Doing that the bridge is still there and no support added. Adding manual support elsewhere seems to work, is that because the height is only 2mm?
RE: Bridge infill versus support
Playing with the concept and support - here's one method to get the quality of the insert a bit more refined: this was done without supports by adding three linear 0.35 pieces to the part to act as bridge piers. I've also done the same using supports, changing spacing to .4 or so, with no interface layers. I haven't tested, but the final improvement is probably by setting solid infill to 0.4 mm instead of 0.45 to allow the unsupported infill to weld to adjacent runs.
RE: Bridge infill versus support
I found a way to turn off bridging in that area, but the result was dismal.
ps: and one of my images in my prior post got lost ... It is the one trial of using extra parts as supports. Bed was getting dirty and adhesion was causing me issues, but the method worked to tame the poor quality of the bridged infill. The three legs break out easily and leave the result shown above. It looks passable for inserting another fitted piece.
Have one last test to run ... thinking my filament is sub par diameter and may be making this harder than it should be. Will do the test with a clean bed ...
RE: Bridge infill versus support
This appears close to best ... turns out my filament is a bit small so these images show about 5% underextrusion. But the finished surface looks pretty good. There isn't any appreciable difference between 0.45 and 0.40 infill.
I'll post an update if adjusting the extrusion ratio helps.
ps: This is what bridging disabled looks like: a total loss.
RE: Bridge infill versus support
ps: and the fun of trying new ways to find a cockroach: trial and error.
RE: Bridge infill versus support
Wow, thanks, you put a number of hours and prints into this.
These settings make a lot better surface. Now I know how little I understand of the slicer settings, and also that material affect the result.
Again thanks for your efforts, I need to do some more work on this.
/ Lars
RE: Bridge infill versus support
You're welcome. I've struggled with droop but never took the time to understand it. This part helped me do that for flat surfaces. So I owe you some thanks, too.