Hey all so I’m trying to get a nice finish on this curve but it seems Studio thinks it needs supports. When I use them it creates an unsightly finish, even if I use dedicated support filament. I have tried to print without supports and it will produce a similar outcome, so I’m thinking there must be something I can do with settings to improve it? It doesn’t seem like too bad an angle to me?
Outcome
What do you think?
Try variable layer height optimized for : Variable Layer Height | Bambu Lab Wiki optimized for quality.
thanks so much I will give it a go tonight!
Yeah it doesn’t seem like a significant overhang… until you break it down. Fillet on corners are actually MASSIVE overhangs by the angle, even though they don’t seem like it. This comes from the initial leading edge which is very subtle.
In the pic below, you can see a quick approximation. I set basic hash marks at 0, 45, and 90 degrees for reference. But the yellow colored angle is the effective angle the printer has to deal with and it is a really tough one (around a 75-85 degree overhang, which is much higher than the generally accepted 45 degree high value). The start angle in this case, is way too much to do cleanly.
There are things you can do to improve this. For example, the smaller the layer height the better the overhang performance will be, that’s why the above suggestion of using the variable layer height option is an excellent choice for improving the printers ability to make this as clean as it can be without support. Unfortunately, this will add time to the print because it is enacting thin layers to help, and thin layers require more layers to build up.
Thanks for the diagram that was really helpful, I can see what you mean now. I am starting a new print now and have used the variable layer height setting and hit the smooth button as many times as possible! I will let you guys know what the outcome is.
Incidentally would a different size nozzle make a difference? Like, would the 0.6mm nozzle be able to create a wider layer that would stand up to a less favourable angle? if that makes sense
The best solution I have found for this situation is to use a chamfer instead of a fillet. Chamfers are hard angles instead of curves. They aren’t nice and smooth, but usually don’t need any support.
If you need to use a fillet, the only solution I have found that really works is to model the support in CAD…and then make that part print with breakaway or soluble filament. I find that with PLA, Aquasys GP works great as a breakaway with no residue…and it can be soluble as well. Here is a pic of how I do it with CAD-modeled support.
You don’t need variable layer heights with this approach. Variable layer heights won’t solve this problem anyway. You may get better overhangs, but as @just4memike pointed out…this is a massive overhang at the bottom and it will never look excellent without a full-interface support.
The smaller the nozzle and layer height the better the overhang performance. Large heights and nozzles require a slightly greater amount of filament hanging over the previous. More so with heights though, but nozzle size does play a part. The nozzle size will require a slightly wider layer which will also require the printer to lay a little bit more plastic farther out, but this is less noticeable.
Below is a super crude display of the part that really matters. The red lines. With thick layers, the overhang on each layer will be greater, thus increasing the chance of sagging. But because the thin layer can stack many more in the same space, the overhanging section can be much smaller.
yeah but my theory was the 0.6mm nozzle would produce a stronger line to support the next
honestly I thought about doing that earlier! crazy haha. I was thinking what if I made some sort of wedge to help it, but then I worried about placing it in the right area, but I guess I could just print it each time. Hmm, you might be onto something here… thanks man
Have you tried printing it on its end? Sometimes just printing it at a different orientation solves the issue.
Yes that’s an option I explored early on but it takes twice as long and twice as much filament because of the supports + I need a textured pei finish on the front of it, either that or the smooth triangular patterned look from the bed I got from china
I simply modeled the support in CAD, and brought the model into the slicer as a STEP file. That allows you to bring in the separate parts together as an assembly. I printed with zero gap of any kind between the objects, and got a pretty much perfect result.
so zero gap and no support filament and it removed okay?
The yellow part is printed in Aquasys GP a support filament that is somewhat similar to PVA. But yes, zero gap.
ah gotcha, I will try it with the support filament ive got tomorrow see how it turns out
How did things end up going?
did you ever find a good solution for this as i am having a similar issue…
No, nothing I tried gave me a nice finish. I tried support filament and have since tried PVA
