Model/Print Feedback/Assistance

[benjamin.cw.nichols]

Hello all, looking for some feedback or assistance on ways to reinforce some specific spots/layers in a model that are rendering weaknesses once printer. Attached are some pictures and files. From the internal views in F3d and Xray in Cura, there don’t appear to be any defects causing layer weakness and the points in the model where either cutouts are former or internal edges are formed. Printing was with Tough Pla at ~75% infill/220C, even those specific layers I added support blockers and printer certain sections at 100%. But with all that, a simple drop on the floor and these weak spots pop the model apart. There are clear visible lines on the outside of the printed model where the weak layers are. Hope I explained that correctly, and feedback/assistance is appreciated. Thanks!

[Drewpan]

Hi,

This seems more like a printing problem than a fusion design problem. The main things in fusion you would need to be

aware of would be beefing up obvious weak spots. Printing lines and weaknesses along them are very difficult to solve

sometimes. I have seen a video that tests the strength of a coarse thread bolt printed upright, sideways and at 45

degrees and the strength differences are marked.

In engineering, material strength is a vital factor to take into account and sometimes some fabrication techniques are

just not viable. The fact that you CAN 3d print something doesn't mean you SHOULD 3d print it if it does not meet the

strength requirements. The biggest issue with 3d printing is that the material prints in layers that are a built in

weakness along that layer. 3d printing is not like welding where the weld is stronger than the material being welded

in many cases.

There may be ways that you can 3d print that will have the desired strength characteristics but it may mean a lot of

testing. Temperature of the print can cause weaker or stronger prints; infill can also affect the print; orientation;

type of material. All of these will need to be tested or another fabrication method found.

Cheers

Andrew

[benjamin.cw.nichols]

Hey Andrew, thanks for the feedback. I've created several structurally sound models that function well as components. However, this specific model has weak points that were highlighted earlier. Despite multiple prints with adjusted settings, these weak areas remain. I'm looking for advice on reinforcing these points in Fusion 360 to make the model sturdier. I've temporarily wrapped the last one in duct tape, which helped, but I'd appreciate any insights you might have. Thanks for any advice!

[laughingcreek]

because of the layer direction, the points it broke at are exactly he locations I would expect to fail.  on  possibility would be to create a channel through the height of the part (normal to the layers) and reinforce with a piece of all thread, putting washers/nuts at either end and putting the part under slight compression across layers.

[wersy]

If something needs to be particularly stable, I primarily use thick walls in addition to more infill.
Also as high a printing temperature as possible and slight over-extrusion.
Which filament do you use?